HK1075779B

HK1075779B - Code conversion/transmission method and apparatus for moving picture data, and code conversion/reception method and apparatus for moving picture data

Info

Publication number: HK1075779B
Application number: HK05109879.2A
Authority: HK
Inventors: 出井洋明; 幡生敦史; 小泽一范
Original assignee: 日本电气株式会社
Priority date: 2002-04-26
Filing date: 2003-04-28
Publication date: 2008-07-25

Description

Moving picture data transcoding/transmitting method and apparatus, and moving picture data transcoding/receiving method and apparatus

Technical Field

The present invention relates to a technique of transmitting coded data, and more particularly, to a method and apparatus for receiving coded moving picture data, converting the coded moving picture data into data that can resist data loss and data errors in a transmission path, and transmitting the converted moving picture data, and a method and apparatus for receiving and decoding the coded moving picture data.

Background

In recent years, a process of efficiently compressing moving picture data according to inter prediction and transmitting encoded data generated by the efficient compression is widely used as a process of efficiently transmitting the moving picture data. According to these processes, prediction parameters obtained by predicting encoded images from time-ordered frames and predicted residual image data are encoded, thereby reducing the information amount of moving image data highly correlated with time. The prediction residual image data is efficiently compressed by the conversion/encoding process and the quantization process, so that moving image data can be transmitted in a small transmission band.

An example of such a process is a process using a compression coding scheme such as MPEG (moving picture experts group) -1, MPEG-2, or MPEG-4. According to these compression coding schemes, an input image frame is divided into rectangular areas of a constant size called macroblocks, inter prediction is performed in each rectangular area according to motion displacement compensation, and the resulting motion vector and prediction residual image data are processed through two-dimensional discrete cosine transform and quantization to convert compressed signal data into variable length codes.

However, according to the conventional moving picture transmission process, if a transmission data error or a transmission packet loss in the form of a long burst occurs, which cannot be recovered even by an error correction code, the receiving side cannot adaptively recover the image data of the frame in which the error occurred.

One countermeasure that the receiving side can use to prevent such an error is to generate an error masking process of image data from image data of a frame that exists before and after the error frame and has been properly decoded, and image data existing around the error area within the error frame, in such a manner as to mask the error. However, even with the error concealment process, the decoded image corruption cannot be eliminated. Furthermore, since the error concealment process relies on inter prediction, image corruption that has occurred will be propagated to subsequent frames.

When information is distributed by multicast/broadcast, data error information or packet loss information of received data cannot be transmitted from a receiver to a sender. If the error information is transmitted to the sender by switching to the receiver, the feedback information occupies the frequency band of the communication path.

Disclosure of Invention

A first object of the present invention is to provide a method and apparatus for transmitting image data so as to be able to mask, at a receiving side, a significant damage of a decoded image due to a transmission error of encoded data at an imperceptible level.

A second object of the present invention is to provide a method and apparatus for enabling a user to set a trade-off between a transmission band that can be used for image data transmission and image quality.

It is a third object of the present invention to provide a method and apparatus for preventing an increase in the amount of computation required to decode compressed encoded data.

A fourth object of the present invention is to provide a method and apparatus for transmitting image data so that a great damage of a decoded image due to a transmission error of encoded data can be masked at a receiving side at an imperceptible level without transmitting feedback information from a receiving side to a transmitting side.

The transcoding/transmitting apparatus according to the present invention is provided with compression-encoded data, and converts and outputs the data to a transmission path, and includes transcoding/transmitting means for transmitting a plurality of encoded data to at least one transmission path, the encoded data including input encoded data and/or encoded data generated by re-encoding the input encoded data. The code conversion/transmission device transmits at least a part of the input encoded data and the re-encoded data to a transmission path.

A transcoding/receiving apparatus according to the present invention receives encoded data transmitted from the above-described converting/transmitting apparatus to a transmission path, the transcoding/receiving apparatus including means for selecting the transmission path on which the data is received, and means for receiving the encoded data from the selected transmission path and reconstructing the encoded data from the encoded data that has been normally received.

The system according to the present invention has the above-described transcoding/transmitting apparatus and a plurality of the above-described transcoding/receiving apparatuses, and may have such a system arrangement that the transcoding/transmitting apparatus receives encoded data transmitted from an apparatus that issues encoded data, and the transcoding/receiving apparatus receives the encoded data.

A moving picture data transcoding/transmitting apparatus according to another aspect of the present invention comprises:

(a) a first moving picture transcoding/transmitting means for supplying thereto the input compressed encoded data and outputting at least one frame of the input encoded data;

(b) second to nth moving picture transcoding/transmitting means for decoding at least a part of the input encoded data, encoding the data obtained by the decoding, and outputting at least one frame of the encoded data thus obtained, wherein N is an integer of 2 or more; and

(c) means for transmitting at least one output from the first to Nth moving picture transcoding/transmitting means to first to Mth transmission paths, where M is an integer of 1 or more.

A transcoding/receiving apparatus of moving picture data according to still another aspect of the present invention is a receiving apparatus for receiving encoded data from the transcoding/transmitting apparatus described above, including:

(d) selecting means for selecting a transmission path for receiving encoded data from the first to mth transmission paths; and

(e) means for receiving the encoded data from the transmission path selected by the selection means, extracting the received encoded data without transmission error and loss, and reconstructing the encoded data from the extracted encoded data and outputting the reconstructed encoded data.

A transcoding/transmitting apparatus of moving picture data according to still another aspect of the present invention, comprises:

(a) a first moving picture transcoding/transmitting means for supplying thereto input compressed encoded packet data and outputting at least a part of the input encoded packet;

(b) second to nth moving picture transcoding/transmitting means for decoding at least a part of input coded packet data, coding data obtained by the decoding, and outputting at least a part of the packet data thus obtained, wherein N is an integer of 2 or more;

A transcoding/receiving apparatus of moving picture data according to still another aspect of the present invention is a receiving apparatus for receiving encoded data from the transcoding/transmitting apparatus, including:

(d) selecting means for selecting one transmission path for receiving encoded data from the first to mth transmission paths; and

(e) means for receiving the encoded data from the transmission path selected by the selection means, extracting the received encoded data packet data having no transmission error and no loss, and reconstructing the encoded data packet data from the extracted encoded data packet data and outputting the reconstructed encoded data packet data.

A transcoding/transmitting method of moving picture data according to still another aspect of the present invention is performed by a transcoding/transmitting apparatus having first to nth moving picture transcoding/transmitting apparatuses, where N is an integer of 2 or more, the method including the steps of:

(a) causing the first moving picture transcoding/transmitting means to be supplied with the input compressed encoded data, and outputting at least one frame of the input encoded data;

(b) causing the second to nth moving picture transcoding/transmitting means to decode at least a part of the input encoded data, encode the data obtained by the decoding, and output at least one frame of the encoded data thus obtained; and

(c) at least one output from the first to Nth moving picture transcoding/transmitting devices is transmitted to first to Mth transmission paths, where M is an integer of 1 or more.

A receiving method according to still another aspect of the present invention includes the steps of:

selecting at least one path (where M is an integer of 1 or more) from M transmission paths, and receiving encoded data from the selected transmission path, extracting the received encoded data without transmission errors and losses, and reconstructing the encoded data from the extracted encoded data and outputting the reconstructed encoded data.

A computer program according to still another aspect of the present invention enables a computer serving as a transcoding/transmitting apparatus of moving picture data to have the following functions:

(a) first moving picture transcoding/transmitting means for supplying thereto the input compressed encoded data and outputting at least one frame of the input encoded data;

(b) second to nth moving picture transcoding/transmitting means for decoding at least a part of the input encoded data, encoding the decoded data, and outputting at least one frame of the encoded data thus obtained, wherein N is an integer of 2 or more; and

(c) means for transmitting at least one output from the first to Nth moving picture transcoding/transmitting means to first to Mth transmission paths, where M is an integer of 1 or more,

thus, the computer executes a transcoding/transmitting process for moving picture data.

A computer program according to still another aspect of the present invention enables a computer serving as a transcoding/receiving apparatus of moving picture data to execute a transcoding/transmitting process of the moving picture data, the program enabling the computer to execute a process of selecting at least one transmission path among M transmission paths, where M is an integer of 1 or more, and a process of receiving encoded data from the selected transmission path, extracting the received encoded data without transmission error and loss, and reconstructing the encoded data from the extracted encoded data and outputting the reconstructed encoded data.

According to the present invention, in order to prevent a decoded image from being significantly damaged by transmission of compression-encoded moving picture data, a transcoding/transmitting apparatus receives encoded data from a moving picture encoding apparatus (server apparatus) serving as an information source, converts the encoded data into a form capable of preventing data loss and data errors on a transmission path, and transmits the converted data to the transcoding/receiving apparatus side.

According to the invention, the transcoding/transmitting means have first to Nth transcoding/transmitting means, where N is an integer of 2 or more, and those transmitting means for the transcoding/transmitting means of the first to Mth transmission paths, where M is an integer of 1 or more. The transcoding/transmitting apparatus compresses the moving picture data into N encoded data, and transmits the encoded data. The transcoding/receiving apparatus side selects and decodes encoded data of good image quality having the lowest compression rate from, for example, encoded data normally received by at least one of the M transmission paths.

According to the present invention, the N encoded data obtained by the first to nth transcoding/transmitting means are transmitted with a constant or adaptively varying time difference. For example, with respect to a frame or a packet, the transcoding/receiving apparatus side serving as a client terminal selects, in units of frames or packets, encoded data of good image quality having the lowest compression rate from among encoded data normally received by, for example, at least one of M transmission paths. The encoded data is transmitted from the transcoding/receiving apparatus to a decoding apparatus (decoder) that decodes the encoded data.

According to the present invention, the compression rate of the first to nth moving picture transcoding/transmitting apparatuses and/or the number of encoded data to be transmitted can be selected according to the transmission band that can be used by the first to mth transmission paths. The second to nth moving picture transcoding/transmitting apparatuses may encode data at a compression rate equal to or higher than that of the first moving picture transcoding/transmitting apparatus, or may set the compression rate to any value.

According to the present invention, in order to prevent an increase in the amount of calculation on the receiving side due to the transmission of a plurality of encoded data, a transcoding/transmitting apparatus generates encoded data including the same frame or the same image area, and the receiving side selects at least one frame or encoded data in units of data packets from the plurality of received encoded data and decodes the selected data.

More specifically, in an apparatus according to the present invention, a transcoding/transmitting apparatus, wherein N represents an integer of 2 or more and M represents an integer of 1 or more, the apparatus comprising:

(a) first moving picture transcoding/transmitting means for supplying compressed encoded data thereto and controlling transmission of all frames or frames adaptively selected according to the properties of an input moving picture or a predetermined rule using predetermined transmitting means;

(b) second to nth moving picture transcoding/transmitting means for decoding at least a portion of the input encoded data, performing compression encoding of the data at a compression rate equal to or higher than that of the first moving picture transcoding/transmitting means, and controlling transmission of all frames of the resulting encoded data or frames adaptively selected according to the properties of the input moving picture or a predetermined rule with a predetermined transmitting means at a constant or adaptively changed transmission time difference; and

(c) and means for selecting compression rates of the first to nth moving picture transcoding/transmitting means and/or the number of encoded data to be transmitted, according to frequency bands that can be used by the first to mth transmission paths, and transmitting the encoded data to the first to mth transmission paths.

The transcoding/receiving means includes selection means for selecting at least one transmission path from the M transmission paths, receiving the N encoded data from the selected transmission path, extracting the received encoded data without transmission error or loss, and selecting and outputting encoded motion picture data of good image quality with the lowest compression rate from, for example, the encoded data in the same frame.

In an apparatus according to a second aspect of the present invention, a transcoding/transmitting apparatus, wherein N represents an integer of 2 or more and M represents an integer of 1 or more, the apparatus comprising:

(a) first moving picture transcoding/transmitting means for supplying thereto compression-encoded data packet data and controlling transmission of all the data packets or data packets adaptively selected according to the nature of an inputted moving picture or a predetermined rule using predetermined transmitting means;

(b) second to nth moving picture transcoding/transmitting means for decoding at least a portion of the input coded data packet data, performing data compression coding into packet data including the same image area as the received packet data at a compression rate equal to or higher than that of the first moving picture transcoding/transmitting means, and controlling to transmit all the obtained packet data with a predetermined transmitting means with a transmission time difference which is constant or adaptively changed or packet data adaptively selected according to the property of the input moving picture or a predetermined rule; and

(c) means for selecting compression rates of the first to nth moving picture transcoding/transmitting means and the number of encoded data to be transmitted, and transmitting the encoded data to the first to mth transmission paths, according to frequency bands that can be used by the first to mth transmission paths.

The transcoding/receiving means includes selecting means for selecting at least one transmission path from the M transmission paths, receiving the N encoded data from the selected transmission path, and, for example, selecting and outputting packet data of good image quality with the lowest compression rate from the received packet data which has been generated by encoding images in the same area of the same frame without transmission errors and losses.

In the apparatus according to the third aspect of the present invention, a transcoding/transmitting apparatus side, wherein N represents an integer of 2 or more and M represents an integer of 1 or more, comprises:

(a) first moving picture transcoding/transmitting means for supplying thereto compression-encoded data, performing compression encoding of all frames of the decoded moving picture data or frames adaptively selected according to the nature of the input moving picture or a predetermined rule at a compression rate equal to or higher than that of the input encoded data, and controlling transmission of at least a part of the thus-obtained encoded data by predetermined transmitting means;

(b) second to nth moving picture transcoding/transmitting means for encoding all frames encoded by the first moving picture transcoding/transmitting means or frames adaptively selected according to the nature of an input moving picture or a predetermined rule at or above a compression rate of the first moving picture transcoding/transmitting means, reusing at least one of inter-prediction parameters and predicted differential image data obtained by inter-prediction performed on the frame by the first moving picture transcoding/transmitting means, and controlling transmission of the obtained encoded data with a transmission time difference that is constant or adaptively changed by the predetermined transmitting means; and

(c) means for selecting compression rates of the first to nth moving picture transcoding/transmitting means and/or the number of encoded data to be transmitted, and transmitting the encoded data to the first to mth transmission paths, according to frequency bands that can be used by the first to mth transmission paths.

In an apparatus according to a fourth aspect of the present invention, a transcoding/transmitting apparatus, wherein N represents an integer of 2 or more and M represents an integer of 1 or more, the apparatus comprising:

(a) first moving picture transcoding/transmitting means for decoding at least a part of the input encoded data packet data, performing compression encoding on the decoded data at a compression rate equal to or higher than that of the input moving picture data, and controlling transmission of at least a part of the encoded data packet data thus obtained by predetermined transmitting means;

(b) second to nth moving picture transcoding/transmitting means for encoding an image area, each of which is encoded in all of the packet data encoded by the first moving picture transcoding/transmitting means or packet data adaptively selected according to the nature of an input moving picture or a predetermined specification, at a compression rate equal to or higher than that of the first moving picture transcoding/transmitting means into a packet including the same image area as the packet data, and then transmitting the resultant encoded packet data with a transmission time difference that is constant or adaptively changed using at least one of inter-prediction parameters and prediction differential image data obtained by inter-prediction performed on the image area by the first moving picture transcoding/transmitting means; and

(c) means for selecting compression rates of the first to nth moving picture transcoding/transmitting means and/or the number of encoded data to be transmitted according to frequency bands that can be used by the first to mth transmission paths, and transmitting the encoded data to the first to mth transmission paths.

The transcoding/receiving means side includes selection means for selecting at least one transmission path from the M transmission paths, receiving the N encoded data from the selected transmission path, and selecting and outputting packet data of good image quality with the lowest compression rate generated by encoding images in the same area of the same frame from, for example, the received packet data without transmission error or loss.

In an apparatus according to a fifth aspect of the present invention, a transcoding/transmitting apparatus, wherein N represents an integer of 2 or more and M represents an integer of 1 or more, comprises:

(a) first moving picture transcoding/transmitting means for supplying thereto compression-encoded data, performing compression encoding of all frames of a decoded moving picture or frames adaptively selected according to the nature of an input moving picture or a predetermined rule at a compression rate equal to or higher than that of the received encoded data, and controlling transmission of at least a part of the thus-obtained encoded data by predetermined transmitting means;

(b) second to nth moving picture transcoding/transmitting means for encoding all frames re-encoded by the first moving picture transcoding/transmitting means or frames adaptively selected according to the nature of an input moving picture or a predetermined rule at a compression rate equal to or higher than that of the first moving picture transcoding/transmitting means, using one reference frame image used in inter prediction performed on the frame by the first moving picture transcoding/transmitting means, and controlling transmission of at least a part of the resulting encoded data at a constant or adaptively varying transmission time difference by the predetermined transmitting means; and

(c) and means for selecting compression rates of the first to nth moving picture transcoding/transmitting means and/or the number of encoded data to be transmitted according to frequency bands that can be used by the first to mth transmission paths, and transmitting the encoded data to the first to mth transmission paths.

The transcoding/receiving means side includes selection means for selecting at least one transmission path from the M transmission paths, receiving the N encoded data from the selected transmission path, extracting the received encoded data without transmission error or loss, and selecting and outputting encoded motion picture data of good image quality with the lowest compression rate from, for example, the encoded data in the same frame.

In an apparatus according to a sixth aspect of the present invention, a transcoding/transmitting apparatus, wherein N represents an integer of 2 or more and M represents an integer of 1 or more, comprises:

(a) first moving picture transcoding/transmitting means for supplying thereto compressed encoded data packet data, performing compression encoding of the decoded moving picture data at a compression rate equal to or higher than that of the input moving picture data, and controlling transmission of at least a part of the encoded data packet data thus obtained by predetermined transmitting means;

(b) second to nth moving picture transcoding/transmitting means for encoding all packet data encoded by the first moving picture transcoding/transmitting means or each encoded image area of the packet data adaptively selected according to the properties of an input moving picture or a predetermined rule into packet data including the same image area as the packet data at a compression rate equal to or higher than that of the first moving picture transcoding/transmitting means, transmitting the resultant packet data with a reference frame used in performing inter prediction on the image area by the first moving picture transcoding/transmitting means, and controlling transmission time difference, which is constant or adaptively changed, by the predetermined transmitting means; and

The transcoding/receiving means includes selecting means for selecting at least one transmission path from the M transmission paths, receiving the N encoded data from the selected transmission path, and selecting and outputting packet data of good image quality having the lowest compression rate generated by encoding images in the same area of the same frame from, for example, the received packet data having no transmission error or loss.

In an apparatus according to a seventh aspect of the present invention, a transcoding/transmitting apparatus, wherein N represents an integer of 2 or more and M represents an integer of 1 or more, the apparatus comprising:

(a) first moving picture transcoding/transmitting means for supplying coded data packet data thereto and controlling transmission of the data using predetermined transmitting means;

(b) second to nth moving picture transcoding/transmitting means for copying packets of all frames encoded by the first moving picture transcoding/transmitting means or packet data adaptively selected according to the nature of an input moving picture or a predetermined rule, and controlling transmission of at least a portion of the resultant packet data with a constant or adaptively varying transmission time difference using predetermined transmitting means; and

(c) means for selecting the number of encoded data to be transmitted of the first to nth moving picture transcoding/transmitting means in accordance with the frequency band that can be used by the first to mth transmission paths, and transmitting the encoded data to the first to mth transmission paths.

The transcoding/receiving means includes selecting means for selecting at least one transmission path from the M transmission paths, receiving the N encoded data from the selected transmission path, and selecting and outputting packet data of good image quality having the lowest compression rate from, for example, received packet data which has been generated by encoding images in the same area of the same frame without transmission errors and losses.

In an apparatus according to an eighth aspect of the present invention, a transcoding/transmitting apparatus, wherein N represents an integer of 2 or more and M represents an integer of 1 or more, the apparatus comprising:

a) first moving picture transcoding/transmitting means for supplying thereto compression-encoded data, decoding at least a part of the input encoded data, performing compression-encoding of the data at a compression rate that is excessively higher than that of the input moving picture data, and controlling transmission of all frames or frames adaptively selected according to the nature of the input moving picture or a predetermined rule using predetermined transmitting means;

b) second to nth moving picture transcoding/transmitting means for decoding at least a portion of the input encoded data, compressing the data at a compression rate equal to or higher than that of the first moving picture transcoding/transmitting means, and controlling to transmit all frames of the resulting encoded data or frames adaptively selected according to the properties of the input moving picture or a predetermined rule with a predetermined transmitting means at a constantly or adaptively varying transmission time difference; and

c) means for selecting compression rates of the first to nth moving picture transcoding/transmitting means and/or the number of encoded data to be transmitted, according to frequency bands that can be used by the first to mth transmission paths, and transmitting the encoded data to the first to mth transmission paths.

The transcoding/receiving means side includes selection means for selecting at least one transmission path from the M transmission paths, receiving the N encoded data from the selected transmission path, extracting the received encoded data without transmission error or loss, and, for example, selecting and outputting encoded motion picture data of good image quality with the lowest compression rate from the encoded data in the same frame.

In an apparatus according to a ninth aspect of the present invention, a transcoding/transmitting apparatus, wherein N represents an integer of 2 or more and M represents an integer of 1 or more, the apparatus comprising:

a) a first moving picture transcoding/transmitting means for supplying thereto compressed encoded data packet data, decoding at least a portion of the inputted encoded data packet data, performing compression encoding of data at a compression rate equal to or higher than that of the inputted encoded data, and controlling transmission of all data packets using a predetermined transmitting means or adaptively selected data packets according to the properties of the inputted moving picture or a predetermined rule;

b) second to nth moving picture transcoding/transmitting means for decoding at least a portion of the input coded packet data, performing compression encoding from data to packet data including the same image area as the received packet data at or above a compression rate of the first moving picture transcoding/transmitting means, and controlling transmission of the packet data obtained with a predetermined transmitting means at a constant or adaptively varying transmission time difference or adaptively selected according to the properties of the input moving picture or a predetermined rule; and

The transcoding/receiving means includes selecting means for selecting at least one transmission path from the M transmission paths, receiving the N encoded data from the selected transmission path, and, for example, selecting and outputting packet data of good image quality with the lowest compression rate from the received packet data that has been generated by encoding images in the same area of the same frame without transmission errors or losses.

According to the present invention, the transcoding/transmitting apparatus may have first to mth transcoding/transmitting processors each having first to nth moving picture transcoding/transmitting apparatuses, where M is an integer of 1 or more, wherein the encoded data outputs of the first to nth moving picture transcoding/transmitting apparatuses of the first to mth transcoding/transmitting processors may be transmitted to the first to mth transmission paths, respectively.

Alternatively, according to the present invention, the transcoding/transmitting apparatus may have first to mth transcoding/transmitting processors each having first to nth moving picture transcoding/transmitting means, where M is an integer of 1 or more, each of the first to mth transcoding/transmitting processors having means for multiplexing and outputting the first to nth encoded data outputs of the first to nth moving picture transcoding/transmitting means in time difference.

A system according to the present invention has a moving picture data encoding device, a transcoding/transmitting device according to any one of the above-described aspects, a plurality of transcoding/receiving devices according to any one of the above-described aspects, and a plurality of decoding devices (decoders) corresponding to the transcoding/receiving devices, wherein encoded data from the encoding device is input to the transcoding/transmitting device, an output from the transcoding/transmitting device is supplied to the plurality of transcoding/receiving devices, and the encoded data from the transcoding/receiving device is supplied to the plurality of decoding devices and decoded.

The present invention is advantageous in that even if a transmission path prone to highly bursty transmission errors and packet loss and low reliability is used, it is possible to reduce the number of encoded data of all original and duplicate packets from being erroneously transmitted, and it is possible to effectively prevent the generated decoded image from being damaged even when packet loss occurs. The reason for this advantage is as follows:

according to the present invention, the transcoding/transmitting apparatus side has first to nth moving picture transcoding/transmitting apparatuses with respect to first to mth transmission paths, where N is an integer of 2 or more and M is an integer of 1 or more. The first moving picture transcoding/transmitting means transmits at least one frame or packet of moving picture data at a certain transmission rate, or decodes and then performs compression encoding of the moving picture data into N encoded data, and transmits the data with a constant or adaptively varying time difference. The second to nth moving picture transcoding/transmitting devices encode the input frame using at least one of an inter-frame prediction parameter or prediction residual image data obtained by encoding the frame by the first moving picture transcoding/transmitting device, or a reference frame image used in the first transcoding/transmitting device. The transcoding/receiving apparatus side selects and decodes, for example, encoded data of good image quality having the lowest compression rate in units of frames or packets from among the encoded data normally received from at least one of the M transmission paths.

According to the present invention, the compression rates of the first to nth motion picture transcoding/transmitting apparatuses and/or the number of encoded data to be transmitted can be selected according to the frequency bands that can be used by the first to mth transmission paths that transmit the motion picture data. Accordingly, the moving picture data can be transmitted according to the condition of the transmission path or the intention of the sender of the moving picture data.

According to the present invention, the second to nth moving picture transcoding/transmitting apparatuses perform encoding at a compression rate equal to or higher than that of the first moving picture transcoding/transmitting apparatus, and can perform transmission control of encoded data regarding a portion of a frame or an image area encoded by the first moving picture transcoding/transmitting apparatus. Therefore, it is possible to prevent an increase in the transmission rate due to the transmission of a plurality of encoded data.

Further, according to the present invention, the transcoding/transmitting apparatus side generates encoded data including the same frame or the same image area, and the transcoding/receiving apparatus side selects and decodes a frame or a packet of one of the received plurality of encoded data. As a result, since the receiving side can decode at least one of the two received encoded data in order to decode the same frame or the same image area, an increase in the amount of calculation required on the receiving side is reduced.

Further, according to the present invention, since the transcoding/transmitting apparatus can reduce the significant destruction of the decoded image caused by the transmission error of the encoded data to a hardly noticeable extent without using the feedback information from the side of the transcoding/receiving apparatus, the increase in traffic due to the transmission of the feedback information is not caused, and the arrangement of the transcoding/transmitting apparatus and the transcoding/receiving apparatus can be simplified.

Drawings

Fig. 1 is a block diagram illustrating the arrangement of a transcoding/transmitting system according to first and second embodiments of the present invention;

fig. 2 is a block diagram illustrating the arrangement of a moving picture transcoding/transmitting apparatus in the system shown in fig. 1;

fig. 3 is a block diagram illustrating one example of an arrangement of a moving picture transcoding/receiving apparatus according to the present invention;

fig. 4 is a flowchart illustrating an encoded data reconstruction sequence performed by the moving picture transcoding/receiving apparatus according to the first embodiment;

fig. 5 is a block diagram illustrating one example of the arrangement of a coded moving picture data packet transmission system according to the present invention;

fig. 6 is a flowchart illustrating an encoded data reconstruction sequence performed by the moving picture transcoding/receiving apparatus according to the second embodiment;

fig. 7 is a block diagram illustrating the arrangement of a transcoding/transmitting system according to the third to sixth embodiments of the present invention;

fig. 8 is a block diagram illustrating the arrangement of the moving picture transcoding/transmitting apparatus according to the third and fourth embodiments;

fig. 9 is a flowchart illustrating an encoded data reconstruction sequence performed by the moving picture transcoding/receiving apparatus according to the third, fifth, and eighth embodiments;

fig. 10 is a flowchart illustrating an encoded data reconstruction sequence performed by the moving picture transcoding/receiving apparatus according to the fourth, sixth, and ninth embodiments;

fig. 11 is a block diagram illustrating the arrangement of a moving picture transcoding/transmitting apparatus according to the fifth and sixth embodiments;

fig. 12 is a block diagram illustrating the arrangement of a transcoding/transmitting system according to a seventh embodiment of the present invention;

fig. 13 is a block diagram illustrating the arrangement of a moving picture transcoding/transmitting apparatus in the system shown in fig. 12;

fig. 14 is a block diagram illustrating the arrangement of a transcoding/transmitting system according to the eighth and ninth embodiments of the present invention;

fig. 15 is a block diagram illustrating the arrangement of a moving picture transcoding/transmitting apparatus in the system shown in fig. 14; and

fig. 16 is a block diagram illustrating a system arrangement according to the tenth embodiment of the present invention.

Detailed Description

(1) The first embodiment:

as shown in fig. 1, according to a first embodiment of the present invention, a transcoding/transmitting apparatus 100, wherein N represents an integer of 2 or more and M represents an integer of 1 or more, has:

a) a first moving picture transcoder/transmitter 102 for supplying compression-encoded data thereto and controlling transmission of all frames or frames adaptively selected according to the nature of an inputted moving picture or a predetermined rule using a predetermined transmission means;

b) a second to nth motion picture transcoder/transmitter 104 for decoding at least a part of the input encoded data, performing compression encoding of data at a compression rate equal to or higher than that of the first motion picture transcoder/transmitter 102, and controlling transmission of all frames of the obtained encoded data or frames adaptively selected according to the property of the input motion picture or a predetermined rule with a time difference which is constant or adaptively changed by using the same or different transmission means as the first motion picture transcoder/transmitter 102; and

c) and a mechanism for selecting compression rates of the first to nth moving picture transcoders/transmitters and/or the number of encoded data to be transmitted, according to frequency bands that can be used by the first to mth transmission paths, and transmitting the encoded data to the first to mth transmission paths.

The transcoding/receiving apparatus 120 includes a reception transmission path selector 107 for selecting at least one transmission path from the M transmission paths, encoded data receivers 108 to 111 for receiving the N encoded data from the selected transmission path and extracting the received encoded data without transmission error or loss, and an encoded data reconstructor 112 for selecting and outputting encoded motion picture data of good image quality with the lowest compression rate from the encoded data in the same frame, for example. The processes and functions of the constituent elements of the code conversion/transmission apparatus 100 and the code conversion/reception apparatus 120 are realized by a program that can be executed by a computer serving as the code conversion/transmission apparatus and the code conversion/reception apparatus.

The first embodiment is described in more detail below:

(1.A) overview:

fig. 1 is a diagram showing the arrangement of the first embodiment of the present invention. As shown in fig. 1, the first embodiment includes a transcoding/transmitting apparatus 100 of moving picture data, a transcoding/receiving apparatus 120, and a transmission path 130 for transmitting encoded data. The integer N represents the number of coded data transmitted by the transcoding/transmitting apparatus 100, and is an integer of 2 or more. The integer M represents the number of transmission paths for which N encoded data are transmitted, and is an integer of 1 or more. The transcoding/apparatus 100 and the transcoding/receiving apparatus 120 are also referred to as a moving picture transcoding/transmitting apparatus and a moving picture transcoding/receiving apparatus, respectively.

Moving picture data is supplied from an encoding apparatus (not shown in fig. 1, see, for example, encoding apparatus 40 in fig. 16) to a transcoding/transmitting apparatus 100, the transcoding/transmitting apparatus 100 encodes the input moving picture data into N encoded data, and transmits the N encoded data as first to N-th encoded moving picture data to first to M-th (M represents an integer of 1 or more) transmission paths 130. As shown in fig. 1, the transcoding/transmitting apparatus 100 has M transcoding/transmitting processors 1 to M corresponding to first to mth transmission paths 130, respectively. The transcoding/transmitting processors 1 to M transmit the encoded data to corresponding first to mth transmission paths 130, respectively.

The transcoding/transmitting processors 1 to M each have N moving picture transcoders/transmitters 102, 104 to 106 of first to nth, and output first to nth encoded data. The transcoding/transmitting processors 2 to M are identical in arrangement to the transcoding/transmitting processor 1, except that they are normally supplied with encoded data that the transcoding/transmitting processor 1 has received. For the sake of simplicity, fig. 1 shows only the arrangement of the transcoding/transmitting processor 1. The code conversion/transmission processor 1 is explained below, and explanations of the code conversion/transmission processors 2 to M are omitted.

The moving picture data receiver 101 in the transcoding/transmitting processor 1 receives the encoded moving picture data. The coded moving picture data is received by the moving picture data receiver 101 of the transcoding/transmitting processor 1 and is also supplied to the transcoding/transmitting processors 2 to M.

The first moving picture transcoder/transmitter 102 transmits at least a part of the frame of the input moving picture data to the moving picture transcoder/receiver 102. The moving picture data decoder 103 decodes the input moving picture data.

The second moving picture transcoder/transmitter 104 performs compression encoding of the moving picture obtained by the moving picture data decoder 103 at a compression rate equal to or higher than that of the first encoded moving picture data, and transmits at least a part of the encoded data to the moving picture transcoder/receiver 120.

If N is 3 or more, the third to nth motion picture transcoders/transmitters 105, 106 encode at least one frame encoded by the first motion picture transcoder/transmitter 102 with at least one of an inter prediction parameter and prediction differential data obtained by inter prediction performed on the frame by the second motion picture transcoder/transmitter 104 at a compression rate equal to or higher than that of the second motion picture transcoder/transmitter 104, and transmit at least a part of the obtained encoded data to the motion picture transcoder/transmitter 120.

The first to nth coded moving picture data from the transcoding/transmitting processors 1 to M are transmitted to the first to mth transmission paths 130. Control of selecting the compression rate of the first to nth moving picture transcoders/transmitters and/or the amount of encoded data to be transmitted and transmitting the data to the first to mth transmission paths 130 may be performed according to the frequency bands that the first to mth transmission paths 130 may use. Instead of using a plurality of transcoding/transmitting processors 1 to M in parallel with each other, the outputs of the first to nth moving picture transcoders/transmitters of one transcoding/transmitting processor 1 may be distributed to the first to mth transmission paths 130. Alternatively, the output paths of the transcoding/transmitting processors 1 to M may be switched from one to another, and the connections of the first to mth transmitting paths may be switched from one to another.

In the moving picture transcoding/receiving apparatus 120, the reception transmission path selector 107 selects at least one transmission path from M transmission paths for which the transcoding/transmitting apparatus has transmitted encoded data. The transcoding/receiving means 120 receives the N encoded data from the selected transmission path, and decodes and converts the encoded data.

As shown in fig. 1, the transcoding receiver receives encoded data from the transmission path selected by the reception transmission path selector 107. The transcoding receiver includes first to nth coded data receivers 108 to 111 that receive coded data transmitted from the first to nth moving picture transcoders/transmitters of the transcoding/transmitting apparatus.

The moving picture transcoding/receiving apparatus has an encoded data reconstructor 112, and outputs from first to nth encoded data receivers 108 to 111 of the transcoding receiver are supplied to the encoded data reconstructor 112.

The encoded data reconstructor 112 selects and outputs encoded motion picture data of good image quality having the lowest compression rate, for example, from the maximum N encoded data received by the first to nth encoded data receivers 108 to 111 without transmission errors or losses. Alternatively, the encoded data reconstructor 112 may select encoded data, for example, encoded data that was originally normally received, from among the received N maximum number of encoded data according to a predetermined decision criterion different from the compression rate, thereby reconstructing the encoded motion picture data. The encoded data reconstructed by the encoded data reconstructor 112 is supplied to a decoding device (not shown) that performs a decoding process of the supplied encoded data.

(1.B) transcoding/transmitting means:

fig. 2 shows a detailed arrangement of a moving picture transcoding/transmitting apparatus according to a first embodiment of the present invention. For the sake of simplicity, it is assumed that the number N of encoded data output from this apparatus is 3, and the number M of transmission paths through which the encoded data is transmitted is 2.

In fig. 2, the first moving picture encoder/transmitter 200 has a first transmission frame/packet selector 201, and a first error detection code additional frame/packet identification number adder 202. The first moving picture encoder/transmitter 200 corresponds to the first moving picture transcoder/transmitter 102 shown in fig. 1.

The first transmission frame/packet selector 201 adaptively selects a frame to be transmitted to the transmission path from among the input moving picture frames according to the characteristics of the image and the condition of the transmission path. For example, the first transmission frame/packet selector 201 may select and output one packet (n packets at a time) at every constant period. Alternatively, the first transmission frame/packet selector 201 refers to a characteristic parameter in a packet of the moving picture frame, and adaptively determines a packet to be transmitted which is selected and encoded. For example, the first transmission frame/packet selector 201 may specify, as characteristic parameters in the encoded packet, parameters, such as a motion vector, which have a large influence on the quality of a decoded image due to a bit error or packet loss, and adaptively determine the encoded packet to be transmitted. Alternatively, if the encoding process is an MPEG process, the first transmission frame/packet selector 201 may use a rule according to the type of image, for example, a rule that an I picture must be selected, and may dynamically change this selection rule.

The first error detection code attached frame/packet identification number adder 202 adds an error detection code and a frame/packet identification number to the receiving apparatus to detect a transmission error and a packet loss of the coded packet data output from the first transmission frame/packet selector 201.

As shown in fig. 2, the second moving picture transcoder/transmitter 220 has a decoder 203, an inter predictor 204, a prediction margin calculator 205, a second prediction error compression encoder 206, a second encoded data packet generator 207, a second error detection code additional frame/packet identification number adder 208, a prediction margin decoder 209, a reference frame memory 211, and a decoded picture calculator 210. The second motion picture transcoder/transmitter 220 corresponds to the second motion picture transcoder/transmitter 104 shown in fig. 1, and the decoder 203 corresponds to the motion picture data decoder 103 shown in fig. 1.

In fig. 2, a decoder 203 decodes at least a part of input coded moving picture data.

The inter predictor 204 performs inter prediction on an input image from at least one decoded image stored in the reference frame memory 211.

The prediction margin calculator 205 calculates a prediction margin by subtracting the prediction image generated by the inter predictor 204 from the input frame image.

The second prediction residual amount compression encoder 206 performs compression encoding of the prediction residual amount image obtained by the prediction residual amount calculator 205 according to a predetermined processing procedure.

The second encoded packet generator 207 converts the inter prediction parameters obtained by the inter predictor 204 and the compressed data of the prediction residual image obtained by the second prediction margin compression encoder 206 into a bit stream according to variable length coding, and outputs the bit stream in predetermined packet units.

The second error-detecting code-attached frame/packet identification number adder 208 adds the error-detecting code and the frame/packet identification number so that the receiving apparatus detects a transmission error and a packet loss of the coded packet data output from the second coded packet generator 207.

The prediction residual decoder 209 determines decoded data of the prediction residual encoded by the second error detection code additional frame/packet identification number adder 208.

The decoded image calculator 210 determines one decoded image by adding the prediction image generated by the inter predictor 204 to the prediction residual decoded by the prediction residual decoder 209.

The reference frame memory 211 stores the decoded image in preparation for encoding the next frame.

In fig. 2, the third moving picture transcoder/transmitter 230 has a third prediction margin compression encoder 212, a third coded data packet generator 213, and a third error detection code additional frame/packet identification number adder 214. The third moving picture transcoder/transmitter 230 corresponds to the third moving picture transcoder/transmitter 105 shown in fig. 1.

The third prediction residual amount compression encoder 212 encodes the prediction residual image obtained by the prediction residual amount calculator 205 at a compression rate equal to or higher than that of the first (second) prediction residual amount compression encoder 206.

The third encoded data packet generator 213 converts the inter prediction parameters obtained by the inter predictor 204 and the compressed data of the prediction residual image obtained by the third prediction margin compression encoder 212 into a bit stream according to variable length coding, and outputs the bit stream in predetermined packet units.

The third error-detecting code-attached frame/packet identification number adder 214 adds the error-detecting code and the frame/packet identification number so that the receiving apparatus detects a transmission error and a packet loss of the compressed packet data output from the third coded packet generator 213.

When the above processor operates, third encoded moving picture data is generated by a predetermined transmission means and transmitted as a packet.

In the present embodiment, since M is 2 and N is 3, encoded moving picture data selected from the above-described first to third encoded moving picture data according to the frequency band that can be used by the transmission path is transmitted to each of the two transmission paths. In fig. 1, two transcoding/transmitting processors 1, 2 are provided, and the transcoding/transmitting processors 1, 2 transmit data to each of three transmission paths.

In the present embodiment, a first error-detecting code-attached frame/packet identification number adder 202 is provided, and an error-detecting code and a frame/packet identification number are added to the first encoded data output from the first transmission frame/packet selector 201. If this information has been added to the incoming motion picture packet data, the first error detection code additional frame/packet identification number adder 202 may not be needed. Alternatively, any other processing procedures may be used as long as they enable the transcoding/receiving apparatus to detect a transmission error and a packet loss of the transmitted encoded packet data. For example, if the first encoded data packet transmission path has a function of detecting a transmission error, the first error-detecting code appended frame/packet identification number adder 202 need not add an error correction code. According to another example, if the encoded data output from the first transmission frame/packet selector 201 includes information capable of identifying a frame and a packet, the first error-detecting code additional frame/packet identification number adder 202 need not add a frame/packet identification number.

Also, although the second error-detecting code-attached frame/packet identification number adder 208 is provided so as to add an error-detecting code and a frame/packet identification number to the second encoded data, any other processes may be used as long as they enable the transcoding/receiving apparatus to detect a transmission error and a packet loss of the transmitted encoded packet data.

Also, although the third error-detecting code-attached frame/packet identification number adder 214 is provided so as to add an error-detecting code and a frame/packet identification number to the third encoded data, any other processing procedures may be used as long as they enable the transcoding/receiving apparatus to detect a transmission error and a packet loss of the transmitted encoded packet data.

According to still another specific example of the present embodiment described above, the moving picture transcoding/transmitting apparatus is connected to an internet communication network, compresses a moving picture captured and input by a CCD (charge coupled device) camera into, for example, encoded data according to an MPEG-4 video scheme, and inputs data to be transmitted through UDP (user datagram protocol)/IP (internet protocol).

In fig. 2, the inter predictor 204 performs inter prediction according to motion displacement compensation. The first prediction residue compression encoder 206 and the third prediction residue compression encoder 212 perform compression processing and quantization according to two-dimensional discrete cosine transform (2D-DCT). The second prediction residue compression encoder 212 compresses the third encoded data at a compression rate equal to or higher than that of the first encoded data according to a process of quantizing 2D-DCT coefficients using a quantization parameter larger than that of the first residue compression encoder 206, or a process of adaptively eliminating higher-order 2D-DCT coefficients. The prediction residual decoder 209 performs inverse quantization and two-dimensional inverse discrete cosine transform (2D-IDCT).

The second coded packet generator 207 codes the quantized DCT coefficients output from the first prediction margin compression encoder 206 and the displacement vector output from the inter predictor 204, and so on, according to syntax prescribed by the MPEG-4 video scheme. Also, the third encoded packet generator 213 encodes the quantized DCT coefficient output from the third prediction margin compression encoder 212 and the displacement vector output from the inter predictor 204, and so on, according to the syntax prescribed by the MPEG-4 video scheme. The first error-detecting code-attached frame/packet identification number adder 202, the second error-detecting code-attached frame/packet identification number adder 208, and the third error-detecting code-attached frame/packet identification number adder 214 generate a UDP datagram including a checksum of error detection to transmit it to a transcoding/receiving device connected to the internet.

(1.C) a transcoding/receiving apparatus:

fig. 3 shows a detailed arrangement of the moving picture transcoding/receiving apparatus 120 (see fig. 1) according to the first embodiment of the present invention. In fig. 3, the moving picture transcoding/receiving apparatus includes a transmission path selector 300, first to third encoded data receivers 320, 330, 340, and an encoded data reconstructor 310.

The first coded data receiver 320 includes a first packet receiving buffer 301, a first coded data extractor 302, and a first error/packet loss detector 303. The second and third coded data receivers are arranged identically to the first coded data receiver.

The reception transmission path selector 300, which is shown as the reception transmission path selector 107 in fig. 1, selects the transmission path 130 (see fig. 1) through which the transcoding/receiving apparatus 120 (see fig. 1) receives the moving picture data. The first packet reception buffer 301 receives first encoded packet data transmitted from the transcoding/transmitting apparatus 100 (see fig. 1). The first coded data extractor 302 extracts coded moving picture data from the packet data received by the first packet receiving buffer 301. The first error/packet loss detector 303 detects a bit error and/or a packet loss generated at the time of the first coded packet data transmission.

In the second encoded data receiver 330, the second packet receiving buffer 304 receives the second encoded packet data output from the transcoding/transmitting apparatus 100 (see fig. 1). The second coded data extractor 305 extracts coded moving picture data from the packet data received by the second packet receiving buffer 304. The second error/packet loss detector 306 detects a bit error and/or a packet loss generated at the time of second encoded packet data transmission.

In the third encoded data receiver 340, the third packet receiving buffer 307 receives the third encoded packet data transmitted from the transcoding/transmitting apparatus 100 (see fig. 1). The third coded data extractor 308 extracts coded moving picture data from the packet data received by the third packet receiving buffer 307. The third error/packet loss detector 309 detects a bit error and/or a packet loss generated at the time of the third encoded packet data transmission.

The encoded data reconstructor 310 reconstructs two encoded data transmitted by the transcoding/transmitting apparatus into one encoded data according to the detection result of the bit error and/or the packet loss from the first to third error/packet loss detectors 303, 306, 309.

The encoded data reconstruction process provided by the encoded data reconstructor 310 in the present embodiment is explained below with reference to a flowchart shown in fig. 4. The sequence of processes shown in fig. 4 represents a sequence of reconstructing encoded data for an nth frame, where n represents an integer.

In step S401, control waits until a time which is the sum of the time at which all encoded data of the nth frame arrives at the first packet reception buffer 301 and the second packet reception buffer 304 and a predetermined allowable maximum delay time. Then, control proceeds to step S402.

In step S402, it is determined whether the nth frame data stored in the first packet reception buffer 301 contains a packet loss and/or a bit error, based on the detection result of the bit error and/or the packet loss from the first error/packet loss detector 303.

If all the encoded data of the nth packet is received in the first packet reception buffer 301 and no error is detected in the data, control is transferred to step S403. Otherwise, control proceeds to step S404.

If control is transferred to step S403, the encoded data of the nth frame is output from the first encoded data extractor 302, and the encoded data reconstruction sequence ends.

If control proceeds from the decision in step S402 to step S404, it is determined whether the nth frame data stored in the second packet reception buffer 304 contains a packet loss and/or a bit error, based on the detection result of the bit error and/or the packet loss from the second error/packet loss detector 306. If all the encoded data of the nth packet is received in the second packet reception buffer 304 and no error is detected in the data, control is transferred to step S405. Otherwise, control proceeds to step S406.

If control proceeds to step S406, it is determined whether the n-th frame data stored in the third packet reception buffer 307 contains a packet loss and/or a bit error, based on the detection result of the bit error and/or the packet loss from the third error/packet loss detector 307. If all the encoded data of the nth packet is received in the third packet reception buffer 307 and no error is detected in the data, control is transferred to step S407. Otherwise, control proceeds to step S403.

In step S407, the encoded data of the nth frame from the third encoded data extractor 308 is output as encoded data to be decoded, and the encoded data reconstruction sequence ends.

In the present embodiment, the process of detecting a transmission error of the first encoded data and/or an erroneous packet loss in the first error/packet loss detector 303 may be any process. For example, the processing procedure may detect a transmission error and/or an erroneous packet loss from the error detection code and the frame/packet number added by the transcoding/transmitting apparatus according to the present embodiment. Alternatively, if the transmission path of the encoded data has an error detection function, the processing may utilize the detection result. If data specifying the encoded frame is contained in the encoded data, the processing may utilize the information contained in the encoded frame.

Also, the process of detecting a transmission error of the second encoded data and/or an erroneous packet loss in the second error/packet loss detector 306 may be any process. The process of detecting a transmission error and/or an erroneous packet loss of the third encoded data in the third error/packet loss detector 309 may be any process.

In step S401 of the encoded data reconstruction sequence performed by the encoded data reconstructor 310, the process of waiting for the reception of the encoded data of the nth frame may be any process as long as it can detect a packet loss while keeping the packet transmission delay within a predetermined range.

If a transmission error or a packet loss is detected in the encoded data received by the third receiving buffer in step S406 of the encoded data reconstruction sequence performed by the encoded data reconstructor 310, that is, if a transmission error or a packet loss occurs in all of the first to third encoded data, the encoded data reconstructor 310 may perform any other process.

In the present embodiment, control proceeds to step S403, and the first encoded data is output as encoded data to be decoded in step S403. However, any other processing procedure may be performed, for example, a processing procedure of stopping the output of the nth frame and using the image data of the (n-1) th frame output before as the output of the nth frame.

In a specific example of the present embodiment, a transcoding/receiving apparatus is connected to an internet communication network, receives packet data transmitted according to a UDP/IP protocol from a transcoding/transmitting apparatus connected to the internet communication network at another location, converts coded moving picture data included in the received UDP datagram, and outputs the converted data to a decoding apparatus. The coded moving picture data is based on the MPEG-4 video scheme. The first error/packet loss detector 303, the second error/packet loss detector 306, and the third error/packet loss detector 309 detect a transmission error by calculating a checksum included in the UDP datagram.

(1.D) transmission mode of coded data packet data:

according to the present invention, the first or second coded packet data may be transmitted from the transcoding/transmitting apparatus 100 (see fig. 1) to the transcoding/receiving apparatus 120 (see fig. 1) according to any process. However, in order to enhance the advantages of the present invention, it is preferable to use a process of reducing correlation between a bit error and a packet loss occurring in the first encoded data packet data and a bit error and a packet loss occurring in the second encoded data packet data, which are generated by encoding the same frame image.

Fig. 5 shows an example of such a preferred process of transmitting encoded packet data. In fig. 5, a transcoding/transmitting apparatus 501 is the transcoding/transmitting apparatus described with reference to fig. 2. Delay adders 502 and 503 add a constant or adaptively varying delay time to the second and third encoded data packet data output from the transcoding/transmitting apparatus 501 and output the resultant data.

The multiplexer 504 multiplexes the first encoded data output from the transcoding/transmitting apparatus 501 shown as the transcoding/transmitting apparatus 100 in fig. 1, the second encoded data output from the delay adder 502, and the third encoded data output from the delay adder 503, and transmits the multiplexed data to the transmission path 505.

The transmission path 505 transmits the data multiplexed by the multiplexer 504 from the transmitting device to the receiving device. Delay adders 506, 507 and multiplexer 508 perform a process of sending similar data to a second transmission path 509.

Transmit path selector 510 selects at least one of transmit path 505 and transmit path 509. The separator 511 receives the data from the transmission path selector 510 and separates the data into first encoded data and second encoded data. The moving picture receiving/decoding apparatus 512 includes the moving picture transcoding/receiving apparatus described with reference to fig. 3.

The delays added to the second and third encoded data by delay adders 502, 503 are determined by the maximum burst time of bit errors and packet losses occurring in transmission path 505. Even if one burst error occurs in the transmission path 505, any one of the first to third encoded data generated by encoding the same frame may be affected by the error to a small extent, which makes it possible to reduce the occurrence of significant image quality degradation due to loss of encoded frame data. The delay is set in the delay adder according to the size of the buffer in the receiving apparatus and the transmission rate (bit rate) of the transmission path.

Also, the delays added to the second and third encoded data by the delay adders 506, 507 are determined by the maximum burst time of bit errors and packet losses occurring in the transmission path 509. Even if a burst error occurs in the transmission path, any one of the first to third encoded data generated by encoding the same frame may be affected by the error to a small extent, which makes it possible to reduce the occurrence of significant image quality degradation due to loss of encoded frame data. A delay adder, or a delay adder and a multiplexer may be provided in the transcoding/transmitting apparatus 501.

(1.E) advantages:

according to the first embodiment, the moving picture transcoding/transmitting apparatus 100 converts the same moving picture data into three encoded data and transmits the encoded data to the transmission path 130 with a constant or adaptively varying time difference.

The first transcoder/transmitter 102 adaptively selects and outputs a frame of the input moving picture data according to the property of the moving picture or a predetermined rule. The second transcoder/transmitter 104 decodes at least a part of the input moving picture data, encodes the data at a compression rate equal to or higher than that of the input data, and transmits the encoded data. The third transcoder/transmitter 105 encodes the frame encoded by the second transcoder/transmitter 104 using at least one of the inter-frame prediction parameter and the prediction residual image data obtained by encoding the frame by the second transcoder/transmitter 104.

The transcoding/receiving means 120 side receives data from at least one of the M transmission paths, and selects encoded data of two image qualities having the lowest compression rates from the normally received encoded data, and outputs it in units of frames.

As a result, even if a low-reliability transmission path in which a high-burstiness of frequent transmission errors and packet loss may occur is used, it is possible to prevent a decoded image generated after data transmission from being significantly corrupted.

By improving the compression rate of the second and third encoded data, the increase in the transmission band due to the transmission of these encoded data can be reduced. Further, it is possible to transmit the first to third encoded data to a plurality of transmission paths having different frequency bands according to the frequency bands that can be used, and to reduce errors that cause influences in the transmission paths. Further, since the moving picture transcoding/receiving apparatus selects at least one of the received three encoded data and outputs it to the moving picture decoding apparatus, the amount of calculation required by the moving picture decoding apparatus does not increase much compared to the ordinary moving picture decoding apparatus.

In the present embodiment, the transcoding/transmitting apparatus and the transcoding/receiving apparatus are used in combination with each other. However, there is no problem if they are used independently of each other. The first to nth transcoded data may have their packets mixed and multiplexed in their sequence according to an interleaving process. The interleaving process may average out the effects of time variations present in the transmit path, such as a circuit.

(2) Second embodiment:

according to a second embodiment of the present invention, a transcoding/transmitting apparatus, wherein N represents an integer of 2 or more and M represents an integer of 1 or more, has:

(a) a first moving picture transcoder/transmitter for supplying thereto compression-encoded data packet data and controlling the transmission of all the data packets or the adaptive selection of the data packets according to the properties of an inputted moving picture or a predetermined rule by using a predetermined transmission means;

(b) second to nth moving picture transcoders/transmitters for decoding at least a portion of the input encoded packet data to perform compression encoding of data into packet data at a compression rate equal to or higher than that of the first moving picture transcoder/transmitter and controlling all the resultant packet data or packet data adaptively selected according to the property of the input moving picture or a predetermined rule to be transmitted with a constant or adaptively varying transmission time difference using a predetermined transmission means; and

a mechanism for selecting compression rates of the first to Nth moving picture transcoders/transmitters and/or the number of encoded data to be transmitted, in accordance with frequency bands that can be used by the first to Mth transmission paths, and transmitting the encoded data to the first to Mth transmission paths.

The transcoding/transmitting apparatus side includes a reception transmission path selector for selecting at least one transmission path from the M transmission paths, receiving the N encoded data from the selected transmission path, and selecting and outputting packet data of two image qualities having the lowest compression rates, for example, from the received packet data which has been generated by encoding one image in the same area in the same frame without transmission errors or losses.

The processes and functions of the constituent elements of the code conversion/transmission apparatus and the code conversion/reception apparatus are realized by programs that can be executed by a computer serving as the code conversion/transmission apparatus and the code conversion/reception apparatus.

The second embodiment is described in more detail below:

(2.A) overview:

the arrangement and operation of the system according to the present embodiment are substantially the same as those of the first embodiment. As shown in fig. 1, the arrangement includes a transcoding/transmitting apparatus 100, a transcoding/receiving apparatus 120, and a transmission path 130 for transmitting encoded data. The integer N transcoding/transmitting apparatus transmits the number of coded data, and is an integer of 2 or more. The integer M code is the number of transmission paths for which N encoded data are transmitted, and is an integer of 1 or more.

The moving picture transcoding/transmitting apparatus 100 has basically the same arrangement as that of the first embodiment, but the operation of the various constituent parts of the apparatus is slightly different. Only the differences between the operation of the present invention and that of the first embodiment are explained below.

The encoded data of the input frame image encoded by the first moving picture encoder/transmitter (first moving picture transcoder/transmitter) includes at least one packet data each including an encoded interframe prediction parameter and encoded compressed differential image data on one image area included in the input frame image. The first moving picture encoder/transmitter 102 transmits at least a part of the packet of the input moving picture to the moving picture transcoding/receiving apparatus.

The second motion picture converter/transmitter (second motion picture transcoder/transmitter) 104 decodes at least a part of the input motion picture data to be equal to or higher than the compression rate of the first encoded motion picture data, performs a predetermined compression encoding process of the resulting image, and transmits at least a part of the encoded data to the motion picture transcoder/receiver.

A third to nth motion picture encoder/transmitter (third to nth motion picture transcoder/transmitter) 105 encoding all packets or images included in the packets encoded by the second motion picture transcoder/transmitter at a compression rate equal to or higher than that of the second motion picture encoder/transmitter, using at least one of an inter prediction parameter and a prediction differential image data obtained by inter prediction performed on the image area by the second motion picture encoder/transmitter, and transmitting at least a part of the obtained encoded data to the motion picture transcoding/receiving apparatus. The other operations are substantially the same as the first embodiment.

The moving picture transcoding/receiving apparatus has basically the same arrangement as that of the first embodiment, but the operation of the various constituent parts of the apparatus is slightly different. Only the differences between the operation of the present embodiment and the operation of the first embodiment are explained below.

As in the first embodiment, the encoded data reconstructor 112 selects a packet of good image quality having the lowest compression rate, for example, from the maximum N encoded data received from the first to nth encoded data receivers which are not transmitted in error or are lost and include compressed data in the same region of the same frame. The coded data reconstructor 112 selects each packet data transmitted by the transcoding/transmitting apparatus. Other operational details are substantially the same as those of the first embodiment.

(2.B) the transcoding/transmitting apparatus:

the arrangement and operation of the moving picture transcoding/transmitting apparatus according to the present embodiment are substantially the same as those of the moving picture transcoding/transmitting apparatus according to the first embodiment shown in fig. 2. However, the operations of the first encoded packet selector 201, the second encoded packet generator 207, the third encoded packet generator 213, the first error-detecting code-added frame/packet identification number adder 202, the second error-detecting code-added frame/packet identification number adder 208, and the third error-detecting code-added frame/packet identification number adder 214 shown in fig. 2 are different from those of the first embodiment. The following description is different and the description of the same parts is omitted.

In the moving picture transcoding/transmitting apparatus according to the present embodiment, the first encoded packet generator 201, the second encoded packet generator 207, and the third encoded packet generator 213 generate the encoded packet data such that the image region included in the encoded packet data selected by the first encoded packet selector 201, the image region included in the encoded packet data generated by the second encoded packet generator 207, and the image included in the encoded packet data generated by the third encoded packet generator 213 are identical to each other.

The first error-detecting code additional frame/packet number adder 202, the second error-detecting code additional frame/packet number adder 207, and the third error-detecting code additional frame/packet number adder 213 operate to add the same packet identification number to the coded packet data corresponding to the same picture area in the same frame. The frame/packet number may not be added if the packet data generated by the first to third encoded packet generators includes information specifying the position of one image area included in the packet data.

A specific example of this embodiment uses the MPEG-4 video scheme to compress moving pictures. According to this scheme, an input image frame is divided into rectangular areas of a constant size called "macroblocks", and compressed, and image information compressed in units of macroblocks is encoded into a bit stream of each packet called a video packet. The video data packet includes compressed data of a desired number of macroblocks in the same frame, and bit stream data of each video data packet encoded by the present process can be decoded. The first coded packet selector 201, the first coded packet generator 207, and the third coded packet generator 213 output coded data for each video packet. The video packet encoded by the second coded packet generator 207 and the video packet encoded by the third coded packet generator 213 are generated such that they include macroblocks in the same area as the video packet selected by the first coded packet selector 201.

(2.C) a transcoding/receiving apparatus:

the arrangement and operation of the moving picture transcoding/receiving apparatus according to the present embodiment are substantially the same as those of the moving picture transcoding/receiving apparatus of the first embodiment shown in fig. 3, except for the operation of the encoded data reconstructor 310 shown in fig. 3. The following description is different and the description of the same parts is omitted.

The encoded data reconstruction sequence performed by the encoded data reconstructor 310 according to the present embodiment is described below with reference to a flowchart shown in fig. 6. The sequence of processes shown in fig. 6 represents a sequence of reconstructing encoded data of an nth frame, where n represents an integer.

In step S601, control waits until a time which is the sum of the time at which all the encoded data of the nth frame reaches the first packet receiving buffer 301, the second packet receiving buffer 304, and the third packet receiving buffer 307 and a predetermined allowable maximum delay time. Then, control proceeds to step S602.

In step S602, the minimum value of the packet number of the nth frame is stored as a variable a for storing one packet number, and the maximum value of the packet number of the nth frame is stored as a variable b.

In step S603, the value of the variable a is set to the variable i for storing one packet number. Then, starting from step S604, the sequence is repeated.

In step S604, it is determined whether the ith packet of the nth frame is present in the first information good reception buffer 301 or whether there is a specific error, based on the detection result of the error and/or the packet loss from the first error/packet loss detector 303. If the ith packet of the nth frame is received in the first packet reception buffer 301 and no error is detected in the data, control proceeds to step S608. Otherwise, control proceeds to step S605.

If control proceeds to step S608, the encoded data of the nth frame output from the first encoded data extractor 302 is output as encoded data to be decoded, and control proceeds to step S610.

If control proceeds to step S605, it is determined whether the ith packet of the nth frame exists or whether a bit error exists in the second packet reception buffer 304, based on the detection result of the error and/or packet loss from the second error/packet loss detector 306. If the ith packet of the nth frame is received in the second packet reception buffer 304 and no error in the data is detected, control proceeds to step S607. Otherwise, control proceeds to step S606.

In step S607, the encoded data of the n-th frame output from the second encoded data extractor 305 is output as encoded data to be decoded, and control proceeds to step S610.

If control proceeds to step S606, it is determined whether the ith packet of the nth frame is present in the third packet reception buffer 307 or whether a bit error is present, based on the detection result of the error and/or packet loss from the third error/packet loss detector 309. If the ith packet of the nth frame is received in the third packet reception buffer 307 and no error in data is detected, control proceeds to step S609. Otherwise, control proceeds to step S610.

In step S610, the variable i is incremented by 1. At step S611 after step S610, it is determined whether the variable i exceeds the value of the variable b. If the variable i does not exceed the value of the variable b, the process is repeated from step S604. If the variable i exceeds the value of the variable b, the repeated sequence is ended, and the sequence for reconstructing the coded data of the n-th frame is ended.

The process of waiting for the encoded data of the n-th frame in step S601 in the encoded data reconstruction sequence performed by the encoded data reconstructor 310 may be any process as long as it can detect a packet loss while keeping the packet transmission delay within a predetermined range.

(2.D) advantages:

according to the second embodiment, the moving picture transcoding/transmitting apparatus converts the same moving picture data into three coded data, and transmits the coded data with a constant or adaptively varying time difference. The second and third motion picture transcoder/transmitters encode image areas included in the packet converted by the first motion picture transcoder/transmitter. The third encoder/transmitter encodes an image area included in the packet converted by the second encoder/transmitter using at least one of the inter prediction parameter and the prediction residual image data obtained by the first moving picture transcoder/transmitter encoding.

The transcoding/receiving apparatus side selects and decodes a packet of encoded data of good picture quality having the lowest compression rate from the encoded data normally received.

As a result, even if a transmission path in which a high burst of frequent transmission errors and packet loss and low reliability may occur is used, the possibility that all three encoded data are erroneously transmitted can be reduced, and the occurrence of significant deterioration of the decoded image generated after data transmission can be prevented.

By improving the compression rate of the second and third encoded data, the increase in the transmission band due to the transmission of the three encoded data can be reduced.

Further, according to the usable frequency band, the first to third encoded data can be transmitted to a plurality of transmission paths having different frequency bands, and the influence of errors in the transmission paths can be reduced.

Further, since the moving picture transcoding/receiving apparatus selects at least one of the received three encoded data and outputs to the moving picture decoding apparatus, the amount of calculation required by the moving picture decoding apparatus does not increase much compared to the ordinary moving picture decoding apparatus.

In the present embodiment, the transcoding/transmitting apparatus and the transcoding/receiving apparatus are used in combination with each other. However, there is no problem if they are used independently of each other.

(3) The third embodiment:

according to a third embodiment of the present invention, a transcoding/transmitting apparatus, wherein N represents an integer of 2 or more and M represents an integer of 1 or more, has:

(a) a first moving picture transcoder/transmitter for supplying compression-encoded data thereto, for compression-encoding all frames of the moving picture data to be decoded or frames adaptively selected according to the nature of the input moving picture or a predetermined rule at or above a compression rate of the input encoded data, and controlling transmission of at least a part of the thus-obtained encoded data by a predetermined transmission means;

(b) second to nth motion picture transcoders/transmitters for encoding all frames encoded by the first motion picture transcoder/transmitter or frames adaptively selected according to a property of an input motion picture or a prescribed rule at or above a compression rate of the first motion picture transcoder/transmitter, reusing at least one of an inter prediction parameter and prediction differential image data obtained by performing inter prediction on the frame by the first motion picture transcoder/transmitter, and transmitting the resultant encoded data with a constant or adaptively varying transmission time difference through the same or different transmission path as that used by the first motion picture transcoder/transmitter; and

(c) a mechanism for selecting compression rates of the first to Nth moving picture transcoding/transmitting apparatuses and/or the number of encoded data to be transmitted, and transmitting the encoded data to the first to Mth transmission paths, in accordance with frequency bands that can be used by the first to Mth transmission paths.

The transcoding/receiving apparatus includes a selector for selecting at least one transmission path from the M transmission paths, receiving the N encoded data from the selected transmission path, extracting the received encoded data without transmission error or loss, and, for example, selecting and outputting encoded moving picture image data of good image quality with the lowest compression rate from the encoded data in the same frame.

The processes and functions of the constituent elements of the code conversion/transmission apparatus and the code conversion/reception apparatus are realized by a program that can be executed by a computer serving as the code conversion/transmission apparatus and the code conversion/reception apparatus.

The third embodiment is described in more detail below:

(3.A) overview:

fig. 7 is a diagram showing the system arrangement of the third embodiment of the present invention. As shown in fig. 7, the third embodiment includes a transcoding/transmitting apparatus 700 for moving picture data, a transcoding/receiving apparatus 720, and a transmission path 730 for transmitting encoded data. The integer N represents the number of coded data transmitted by the transcoding/transmitting apparatus, and is an integer of 2 or more. The integer M represents the number of transmission paths 730 to which the N encoded data are transmitted, and is an integer of 1 or more.

The moving picture transcoding/transmitting apparatus 700 decodes at least a part of the input encoded moving picture data, performs compression encoding processing of the resulting image at a compression rate equal to or higher than that of the input image, and transmits the transcoded data to the moving picture transcoding/receiving apparatus 720. The moving picture transcoding/transmitting 700 encodes the input moving picture data into N encoded data and transmits the encoded data as first to nth encoded moving picture data to the first to mth transmission paths 730.

As shown in fig. 7, the apparatus has first to nth motion picture encoders/transmitters (first to nth motion picture transcoders/transmitters) 703 to 705.

The moving picture data receiver 701 receives moving picture data. The moving picture decoder 702 decodes at least a portion of the input encoded moving picture data.

The first moving picture encoder/transmitter (first moving picture transcoder/transmitter) 703 performs a predetermined compression encoding process of a frame input to the transcoding/transmitting apparatus (transcoder/transmitter), and controls transmission of at least a part of the resulting encoded data to the moving picture transcoding/receiving apparatus. The second to nth motion picture encoders/transmitters (second to nth motion picture transcoders/transmitters) 704, 705 encode at least one frame encoded by the first motion picture encoder/transmitter 703 with at least one of an inter prediction parameter and prediction differential image data obtained by inter prediction performed on the frame by the first motion picture encoder/transmitter at a compression rate equal to or higher than that of the first motion picture encoder/transmitter 703, and transmit at least a part of the resulting encoded data to the motion picture transcoding/receiving apparatus 720 via a transmission path 730. Among the first to nth encoded moving picture data, encoded moving picture data selected according to a frequency band that can be used by a transmission path is transmitted to the first to mth transmission paths.

In the moving picture transcoding/transmitting apparatus 720, the reception transmission path selector 706 selects at least one transmission path from M transmission paths for which the moving picture transcoding/transmitting apparatus has transmitted encoded data. The moving picture transcoding/receiving means 720 receives the N encoded data from the selected transmission path and decodes the encoded data.

As shown in fig. 7, the moving picture transcoding/receiving apparatus 720 includes first to nth encoded data receivers 707 to 709 for receiving encoded data transmitted to a transmission path 730 by the first to nth moving picture transcoders/transmitters 703 to 705 of the transcoding/transmitting apparatus 700, and an encoded data reconstructor 710. For example, the encoded data reconstructor 710 selects and outputs data of good image quality having the lowest compression rate from the maximum N encoded data received by the encoded data receivers 707 to 709 without transmission errors or losses.

(3.B) the transcoding/transmitting apparatus:

fig. 8 shows a detailed arrangement of a moving picture transcoding/transmitting apparatus according to the third embodiment. For the sake of simplicity, it is assumed in fig. 8 that the number N of encoded data output from the present apparatus is 3, and the number M of transmission paths for transmitting the encoded data is 2.

In fig. 8, a decoder 801 decodes at least a part of input coded motion picture data. The inter predictor 802 inter-predicts one picture output from the decoder 801 from at least one decoded picture stored in the reference frame memory 809. The prediction margin calculator 803 calculates a prediction margin by subtracting the prediction image generated by the inter predictor 802 from the input frame image. The first prediction residual compression encoder 804 performs compression encoding of the prediction residual image obtained by the prediction residual calculator 803 according to a predetermined processing procedure. The first encoded packet generator 805 converts the inter prediction parameters obtained by the inter predictor 802 and the compressed data of the prediction residual image obtained by the first prediction margin compression encoder 804 into a bitstream according to variable length coding, and outputs the bitstream in units of predetermined packets. The first error detection code adds the frame/packet identification number adder 806 adds the detection code and the frame/packet identification number so that the receiving apparatus detects a transmission error and a packet loss of the coded packet data output from the first coded packet generator 805. The prediction residual decoder 807 determines decoded data of the prediction residual encoded by the first error detection code additional frame/packet identification number adder 806. The decoded image calculator 808 determines a decoded image by the sum of the prediction image generated by the inter predictor 802 and the prediction residue decoded by the prediction residue decoder 807. The reference frame memory 809 stores the decoded image in preparation for encoding the next frame.

In fig. 8, the second prediction residual amount compression encoder 810 encodes the prediction residual image obtained by the prediction residual amount calculator 803 at a compression rate equal to or higher than that of the first prediction residual amount compression encoder. The second encoded packet generator 811 converts the inter prediction parameters obtained by the inter predictor 802 and the prediction residual image obtained by the second prediction margin compression encoder 810 into a bitstream according to variable length coding, and outputs the bitstream in units of predetermined packets. The second error code-attached frame/packet identification number adder 812 adds an error detection code and a frame/packet identification number so that the receiving apparatus detects a transmission error and a packet loss of the compressed packet data output from the second coded packet generator 811. In this way, the second coded moving picture data is generated and transmitted as a packet by a predetermined transmission mechanism.

In the present embodiment, since M is 2 and N is 2, encoded moving picture data selected according to a frequency band that can be used by a transmission path from the above-described first and second encoded moving picture data is transmitted to each of two transmission paths.

In the present embodiment, a first error-detecting code-appended frame/packet identification number adder 806 is provided, and the first error-detecting code-appended frame/packet identification number adder 806 adds an error-detecting code and a frame/packet identification number to the first encoded data output from the first encoded data packet generator 805. However, any other processes may be used as long as they enable the transcoding/receiving apparatus to detect a transmission error and a packet loss of the transmitted packet data. For example, if the first encoded data packet transmission path has a mechanism to detect transmission errors, the first false detection code addition frame/packet identification number adder 806 need not add an error correction code. According to another example, if the encoded data output from the first encoded data packet generator 805 includes information capable of identifying a frame and a data packet, the error-detecting code addition frame/data packet identification number adder 806 need not add a frame/data packet identification number.

Also, although the second error-detecting code-attached frame/packet identification number adder 812 is provided to add the error-detecting code and the frame/packet identification number to the second encoded data, any other processes may be used as long as they enable the transcoding/receiving apparatus to detect a transmission error and a packet loss of the transmitted encoded packet data.

One preferable specific example of the present embodiment described above is the same as that of the first embodiment described above.

(3.C) a transcoding/receiving apparatus:

the arrangement of the moving picture transcoding/receiving apparatus according to the third embodiment of the present invention is the same as that shown in fig. 3. However, although the number M of transmission paths in fig. 3 is 3, it is 2 in the present embodiment, and thus there is no third encoder/receiver in the present embodiment. Since M is 2, the encoded data reconstructor 310 has a different operation sequence.

The operational sequence of the encoded data reconstructor 310 according to the present embodiment is explained below with reference to the flowchart of fig. 9. The sequence of processes shown in fig. 9 represents a sequence of reconstructing encoded data for an nth frame, where n is an integer.

In step S901, control waits until a time which is the sum of the time at which all encoded data of the nth frame arrives at the first packet reception buffer 301 and the second packet reception buffer 304 and a predetermined allowable maximum delay time. Then, control proceeds to step S902.

In step S902, it is determined whether or not the nth frame data is present in the first packet reception buffer 301 and whether or not there is a bit error, based on the detection result of the bit error and/or the packet loss from the first error/packet loss detector 303. If all the encoded data of the nth packet is received in the first packet reception buffer 301 and no error is detected in the data, control proceeds to step S903. Otherwise, control proceeds to step S904.

If control proceeds to step S903, the encoded data of the n-th frame supplied from the first encoded data extractor 302 is transmitted to a variable length decoder (not shown, but included in, for example, a decoding apparatus shown in fig. 16) as encoded data to be decoded, and the encoded data reconstruction sequence is ended.

If control proceeds to step S904, it is determined whether or not the nth frame data is present in the second packet reception buffer 304 and whether or not there is a bit error, based on the detection result of the bit error and/or the packet loss from the second error/packet loss detector 306. If all the encoded data of the nth packet is received in the second packet reception buffer 304 and no error is detected in the data, control proceeds to step S905. Otherwise, control proceeds to step S903.

In step S905, the encoded data of the n-th frame from the second encoded data extractor 305 is transmitted to a variable length decoder (not shown, but included in the decoding apparatus shown in fig. 16, for example) as encoded data to be decoded, and the encoded data reconstruction sequence ends.

The operation and preferred specific example of the other parts of this embodiment are the same as those of the first embodiment.

(3.D) advantages:

according to the third embodiment, the moving picture transcoding/transmitting apparatus decodes at least a part of the input moving picture data, encodes the same moving picture data into two encoded data, and transmits the encoded data with a time difference that is constant or adaptively changed. And a second moving picture transcoder/transmitter for encoding the frame encoded by the first moving picture transcoder/transmitter using at least one of an inter-frame prediction parameter obtained by encoding the frame with the first moving picture transcoder/transmitter and prediction residual image data.

The transcoding/receiving apparatus side selects and outputs encoded data of good image quality having the lowest compression rate in units of packets from the normally received encoded data.

As a result, even if a transmission path in which a high degree of bursty frequent transmission errors and packet loss and low reliability may occur is used, the possibility that both encoded data are erroneously transmitted is reduced, preventing the decoded image from being seriously damaged after data transmission.

By improving the compression rate of the second encoded data, the increase of the transmission band due to the transmission of the second encoded data can be reduced.

Further, the first and second encoded data can be transmitted to a plurality of transmission paths having different frequency bands according to the condition of the transmission path and the intention of the moving picture transmitter or the moving picture receiver, and the influence of an error in the transmission path can be reduced.

Further, since at least one of the received two encoded data is selected by the moving picture transcoding/receiving apparatus and output to the moving picture decoding apparatus by the moving picture transcoding/receiving apparatus, the amount of calculation required by the moving picture decoding apparatus does not increase much compared to the ordinary moving picture decoding apparatus.

In the present embodiment, the transcoding/transmitting apparatus and the transcoding/receiving apparatus are used in combination with each other. However, there is no problem if they are used independently of each other. The first to nth transcoded data may be transmitted in a staggered manner, rather than in an interval period manner.

(4) The fourth embodiment:

according to a fourth embodiment of the present invention, a transcoding/transmitting apparatus, wherein N represents an integer of 2 or more and M represents an integer of 1 or more, has:

(a) a first moving picture transcoder/transmitter for decoding at least a part of an input coded packet, performing compression coding of data at a compression rate equal to or higher than that of the input moving picture data, and controlling transmission of at least a part of the coded packet thus obtained with a predetermined transmission means;

(b) a second to Nth moving picture transcoder/transmitters for encoding an image area, which is encoded by all packet data encoded by the first moving picture transcoder/transmitter or each packet data of packet data adaptively selected according to a property of an inputted moving picture or a predetermined rule, into one packet data at a compression rate equal to or higher than that of the first moving picture transcoder/transmitter, and then using at least one of an inter prediction parameter and a prediction differential image data obtained by inter prediction of the image area with the first moving picture transcoder/transmitter, and controlling the obtained encoded data packet data to be transmitted with a transmission apparatus which is the same as or different from the transmission apparatus used by the first moving picture converter/transmitter at a transmission time difference which is constantly or adaptively changed; and

(c) means for selecting compression rates of the first to nth moving picture transcoders/transmitters and/or the number of encoded data to be transmitted according to frequency bands that can be used by the first to mth transmission paths, and transmitting the encoded data to the first to mth transmission paths.

The apparatus in the receiving side includes a selector for selecting at least one transmission path from the M transmission paths, receiving N encoded data from the selected transmission path, selecting and outputting encoded data packet data of good image quality having the lowest compression rate from, for example, encoded data packet data generated by encoding images in the same area of the same frame.

The fourth embodiment is described in more detail below:

(4.A) overview:

the arrangement and operation of the present embodiment are substantially the same as those of the third embodiment. As shown in fig. 7, the present embodiment includes a transcoding/transmitting apparatus, a transcoding/receiving apparatus, and a transmission path for transmitting encoded data. The integer N represents the number of coded data transmitted by the transcoding/transmitting apparatus, and is an integer of 2 or more. The integer M represents the number of transmission paths for which N encoded data are transmitted, and is an integer of 1 or more.

The code conversion/transmission apparatus has basically the same arrangement as that of the third embodiment, but the operation of the various constituent parts of the apparatus is slightly different. Only the differences will be described below, and the description of the same parts will be omitted.

The moving picture transcoding/transmitting processor decodes at least a part of the input encoded moving picture data to be equal to or higher than the compression rate of the input moving picture data, performs compression encoding processing of the resulting image, and transmits the encoded data to the moving picture transcoding/receiving apparatus. The encoded data of the input frame image encoded by the moving picture transcoding/transmitting processor includes at least one packet data, each of which includes an encoded interframe prediction parameter and encoded compressed differential image data on an image area included in the input frame image. And second to Nth moving picture encoders/transmitters which encode the image area included in at least one packet encoded by the first moving picture encoder/transmitter with at least one of an inter prediction parameter and a prediction differential image data obtained by performing inter prediction on the image area by the first moving picture encoder/transmitter at a compression rate equal to or higher than that of the first moving picture encoder/transmitter, and transmit the resulting packet data to the moving picture transcoding/receiving apparatus. Other operational details are substantially the same as the third embodiment.

The moving picture transcoding/receiving apparatus has substantially the same arrangement as that of the third embodiment, but the operation of the various constituent parts of the apparatus is slightly different. Only the differences will be described below, and the description of the same parts will be omitted.

According to the present embodiment, as shown in fig. 7, as with the third embodiment, the encoded data reconstructor 710 selects, as encoded data to be decoded, at least one packet data of good image quality having the lowest compression rate, for example, the maximum N encoded data packet data received from the first to nth encoded data receivers without transmission error or loss. The coded data reconstructor 710 performs selection in units of packet data output from the transcoding/transmitting apparatus. Other operational details are substantially the same as those of the third embodiment.

(4.B) the transcoding/transmitting means:

the arrangement and operation of the moving picture transcoding/transmitting apparatus according to the present embodiment are substantially the same as those of the moving picture transcoding/transmitting apparatus according to the third embodiment shown in fig. 8. However, the operations of the first coded packet generator 805, the second coded packet generator 811, the first error-detecting code-added frame/packet number adder 806, and the second error-detecting code-added frame/packet number addition 812 are different from those of the third embodiment.

In the moving picture data transcoding/transmitting apparatus according to the present embodiment, the first encoded packet generator 805 and the second encoded packet generator 811 generate encoded packet data such that an image area included in the encoded packet data generated by the first encoded packet generator 805 and an image area included in the encoded packet data generated by the second encoded packet generator 811 are identical to each other.

The first error-detecting code-appended frame/packet number adder 806 and the second error-detecting code-appended frame/packet number adder 812 operate to add the same packet identification number to the encoded packet data corresponding to the same picture region in the same frame. If the packet data generated by the first and second packet generators includes the frame number and information specifying the position of the picture region included in the packet data, the frame/packet identification number may not be added.

The operation of the other processors not illustrated is the same as that of the third embodiment. A preferred specific example of the above embodiment is the same as that of the above second embodiment.

(4.C) a transcoding/receiving apparatus:

the arrangement and operation of the moving picture transcoding/receiving apparatus according to the present embodiment are substantially the same as those of the moving picture transcoding/receiving apparatus according to the second embodiment shown in fig. 3. However, although the number M of transmission paths is 3 in fig. 3, it is 2 in the present embodiment, and therefore, there is no third encoder/receiver in the present embodiment. Since M is 2, the encoded data reconstructor 310 has a different operation sequence.

The operational sequence of the encoded data reconstructor 310 according to the present embodiment is explained below with reference to a flowchart shown in fig. 10. The sequence of the process shown in fig. 10 represents the sequence of encoded data used to reconstruct the nth frame, where n represents an integer.

In step S1001, control waits until a time that is the sum of the time at which all encoded data of the nth frame reaches the first packet reception buffer 301 and the second packet reception buffer 304 and a predetermined allowable maximum delay time. Then, control proceeds to step S1002.

In step S1002, the minimum value of the packet number of the nth frame is stored as a variable a for storing the packet number, and the maximum value of the packet number of the nth frame is stored as one variable b.

In step S1003, the value of the variable a is input to the code i to store the packet number. Then, the sequence from step S1004 is repeated.

In step S1004, it is determined whether the ith packet of the nth frame is present in the first packet reception buffer 301 or whether a bit error is present, based on the detection result of the error and/or packet loss from the first error/packet loss detector 303. If the ith packet of the nth frame is received in the first packet reception buffer 301 and no error is detected in the data, control proceeds to step S1005. Otherwise, control proceeds to step S1006.

If control proceeds to step S1005, the encoded data of the nth frame output from the first encoded data extractor 302 is transmitted to the variable length decoder 308 as encoded data to be decoded. Then, control proceeds to step S1008.

If control proceeds to step S1006, it is determined whether the ith packet of the nth frame is present in the second packet reception buffer 304 or whether there is a bit error, based on the detection result of the error and/or packet loss from the second error/packet loss detector 306. If the ith packet of the nth frame is received in the second packet reception buffer 304 and no error is detected in the data, control proceeds to step S1007. Otherwise, control proceeds to step S1008.

In step S1007, the encoded data of the nth frame output from the second encoded data extractor 305 is transferred to the variable length decoder 308 as encoded data to be decoded. Then, control proceeds to step S1008.

In step S1008, the variable i is incremented by 1. In step S1009 after step S1008, it is determined whether the variable i exceeds the value of the variable b. If the variable i does not exceed the value of the variable b, the process is repeated from step S1004. If the variable i exceeds the value of the variable b, the repetition sequence is complete and the sequence of reconstructing the encoded data for the nth frame ends.

The operation and preferred specific example of the other parts of this embodiment are the same as those of the third embodiment.

(4.D) advantages:

according to the fourth embodiment of the present invention, a moving picture transcoding/transmitting apparatus decodes at least a part of input moving picture data, encodes the same moving picture data into two encoded data, and transmits the encoded data with a constant or adaptively varying time difference.

And a second moving picture transcoder/transmitter for encoding an image area included in the packet encoded by the first moving picture transcoder/transmitter using at least one of an interframe prediction parameter and prediction residual image data obtained by encoding the frame by the first moving picture transcoder/transmitter.

The transcoding/receiving apparatus side selects and outputs encoded data of good image quality having the lowest compression rate in units of packets from the encoded data normally received.

As a result, even if a highly bursty transmission error and packet loss that frequently occur and a transmission path with low reliability is used, the possibility that both encoded data are erroneously transmitted is reduced, preventing the decoded image generated after data transmission from being seriously deteriorated.

Further, the first and second encoded data may be transmitted to a plurality of transmission paths having different frequency bands according to the condition of the transmission path and the intention of the moving picture transmitter or the moving picture receiver.

Further, since at least one of the received two encoded data is selected by the moving picture transcoding/receiving apparatus and output to the moving picture decoding apparatus by the moving picture transcoding/transmitting apparatus, the amount of calculation required by the moving picture decoding apparatus does not increase much compared to the general moving picture decoding apparatus.

(5) Fifth embodiment:

according to a fifth embodiment of the present invention, a transcoding/transmitting apparatus side, wherein N represents an integer of 2 or more, and M represents an integer of 1 or more has:

(a) a first moving picture transcoder/transmitter for supplying compression-encoded data thereto so as to be equal to or higher than a compression rate of the input-encoded data, performing compression encoding of all frames of decoded moving picture data or frames adaptively selected according to a property of the input moving picture or a predetermined rule, and controlling transmission of at least a part of the thus-obtained encoded data by a predetermined transmission means;

(b) second to nth motion picture transcoders/transmitters encoding all frames re-encoded by the first motion picture transcoder/transmitter or frames adaptively selected according to a property of an input motion picture or a predetermined rule with a compression rate equal to or higher than that of the first motion picture transcoder/transmitter using one reference frame image used in the first motion picture transcoder/transmitter to perform inter prediction on the frame, and controlling to transmit at least a part of the resulting encoded data with a transmission time difference that is constant or adaptively changed using the same or different transmission means as that used by the first motion picture transcoder/transmitter; and

(c) and a mechanism for selecting compression rates of the first to nth moving picture code transmitters/transmitters and/or the number of encoded data to be transmitted according to frequency bands that can be used by the first to mth transmission paths, and transmitting the encoded data to the first to mth transmission paths.

The transcoding/receiving apparatus side includes a selector for selecting at least one transmission path from the M transmission paths, receiving the N encoded data from the selected transmission path, extracting the received encoded data without transmission error or loss, and, for example, selecting and outputting encoded motion picture data of good image quality with the lowest compression rate from the encoded data in the same frame.

The fifth embodiment is described in more detail below:

(5.A) overview:

the arrangement and operation of the system according to the present embodiment are substantially the same as those of the third embodiment. As shown in fig. 7, the present embodiment includes a transcoding/transmitting apparatus for moving picture data, a transcoding/receiving apparatus, and a transmission path for transmitting encoded data. The integer N represents the number of coded data transmitted by the transcoding/transmitting apparatus, and is an integer of 2 or more. The integer M represents the number of transmission paths for which N encoded data are transmitted, and is an integer of 1 or more.

The second to nth moving picture encoders/transmitters decode at least a part of the input encoded moving picture data, perform a predetermined compression encoding process of the resulting image at a compression rate equal to or higher than that of the input moving picture data, and transmit at least a part of the transcoded data to the moving picture transcoding/receiving apparatus. In the second to nth motion picture encoders/transmitters, an input frame image is encoded using a reference image used in performing inter prediction on a frame in the first motion picture encoder/transmitter. Alternatively, interframe prediction and predictive differential image data obtained by interframe prediction performed under control different from that of the first motion picture encoder/transmitter, which is different from that in the first motion picture encoder/transmitter, may be encoded. Other operational details are substantially the same as those of the third embodiment.

(5.B) transcoding/transmitting means:

fig. 11 shows a detailed arrangement of a moving picture transcoding/transmitting apparatus according to the fifth embodiment. For simplicity, it is assumed that the number N of encoded data output from the apparatus is 2. In fig. 11, reference numerals 1101 to 1109 denote processors of the first moving picture encoder/transmitter of the moving picture transcoding/transmitting apparatus according to the present embodiment. These processors operate in the same manner as the processor of the first moving picture transcoder/transmitter shown in fig. 8. In fig. 11, the inter predictor 1110, the prediction residual amount calculator 1111, the second prediction residual amount compression encoder 1112, and the second encoded data packet generators 1113, 1114 serve as processors of the second motion picture encoder/transmitter of the motion picture conversion/transmission apparatus according to the present embodiment. However, the operation of these processors is different from that of the moving picture encoder/transmitter according to the first embodiment.

The inter predictor 1110 performs inter prediction of an input image input from the decoder 1101 from at least one decoded image stored in the reference frame memory 1109. The prediction margin calculator 1111 calculates a prediction margin by subtracting the prediction image generated by the inter predictor 1110 from the input frame image. The second prediction residual compression encoder 1112 encodes the prediction residual image obtained by the prediction residual calculator 1111 at a compression rate equal to or higher than that of the first prediction residual compression encoder 1104. According to the variable length coding, the second coded data packet generator 1113 converts the inter prediction parameters obtained by the inter predictor 1110 and the compressed data of the prediction residual image obtained by the second prediction residual amount compression encoder 1112 into a bitstream, and outputs the bitstream in units of prediction data packets. The second error detection code is added with the frame/packet identification number adder 1114 to add the error detection code and the frame/packet identification number so that the receiving apparatus detects a transmission error and a packet loss of the compressed packet data output from the second encoded packet generator 1113. The processor operates to generate second encoded moving picture data and output it in units of data packets by a predetermined transmitting device.

(5.C) advantages:

according to a fifth embodiment of the present invention, a moving picture transcoding/transmitting apparatus decodes at least a part of input moving picture data, encodes the same moving picture data into two encoded data, and transmits the encoded data with a time difference that is constant or adaptively changes.

The second motion picture transcoder/transmitter encodes the frame encoded by the first motion picture transcoder/transmitter using the reference frame image used in encoding the frame by the first motion picture transcoder/transmitter.

The transcoding/receiving apparatus side selects and outputs encoded data of good image quality having the lowest compression rate in units of frames from the encoded data normally received.

As a result, even if a low-reliability transmission path in which a high burst of frequent transmission errors and packet loss may occur is used, the possibility that both encoded data are erroneously transmitted is reduced, preventing the decoded image generated after data transmission from being seriously deteriorated.

Further, it is possible to transmit the first and second encoded data to a plurality of transmission paths having different frequency bands according to the condition of the transmission paths and the intention of the moving picture sender and the moving picture receiver, and reduce the influence of errors in the transmission paths.

Further, since the moving picture transcoding/receiving apparatus selects at least one of the received two encoded data and outputs it to the moving picture decoding apparatus through the moving picture transcoding/receiving apparatus, the amount of calculation required by the moving picture decoding apparatus does not increase much compared to the general moving picture decoding apparatus.

In the present embodiment, the transcoding/transmitting apparatus and the transcoding/receiving apparatus are used in combination with each other. However, there is no problem in using them independently of each other. The first to nth transcoded data may be transmitted in a staggered manner, not in an interval period manner.

(6) Sixth embodiment:

according to a sixth embodiment of the present invention, a transcoding/transmitting apparatus side, wherein N represents an integer of 2 or more and M represents an integer of 1 or more, has:

(a) a first moving picture code converter/transmitter for supplying thereto compressed encoded data packet data, performing compression encoding of decoded moving picture data at a compression rate equal to or higher than that of the inputted moving picture data, and controlling transmission of at least a part of the encoded data packet data thus obtained with a predetermined transmission means;

(b) second to nth moving picture transcoders/transmitters for encoding each of all packet data encoded by the first moving picture transcoder/transmitter or an image area encoded by packet data adaptively selected according to a property of an inputted moving picture or a predetermined rule into packet data at a compression rate equal to or higher than that of the first moving picture transcoder/transmitter, using a reference frame image used in inter prediction performed on the image area by the first moving picture transcoder/transmitter, and controlling transmission of at least a part of the resulting encoded data with a predetermined transmission means at a time difference that is constant or adaptively changed; and

(c) and a mechanism for selecting compression rates of the first to nth moving picture transcoders/transmitters and/or the number of encoded data to be transmitted, according to frequency bands that can be used by the first to mth transmission paths, and transmitting the encoded data to the first to mth transmission paths.

The transcoding/receiving apparatus side includes a selector for selecting at least one transmission path from the M transmission paths, receiving the N encoded data from the selected transmission path, and, for example, selecting and outputting encoded data packet data of good image quality with the lowest compression rate from encoded data packet data generated by encoding images in the same image area in the same frame.

The sixth embodiment is described in more detail below:

(6.A) overview:

the system arrangement according to the present embodiment is substantially the same as that of the fifth embodiment. As shown in fig. 7, the present embodiment includes a transcoding/transmitting apparatus for moving picture data, a transcoding/receiving apparatus, and a transmission path for transmitting encoded data. The integer N represents the number of coded data transmitted by the transcoding/transmitting apparatus, and is an integer of 2 or more. The integer M represents the number of transmission paths for which N encoded data are transmitted, and is an integer of 1 or more.

The moving picture transcoding/transmitting apparatus has basically the same arrangement as the fifth embodiment, but the operation of the various constituent parts of the apparatus is slightly different. Only the differences are explained below.

The first moving picture encoder/transmitter decodes at least a portion of the input encoded moving picture data and encodes the resulting image at a compression rate equal to or higher than that of the input moving picture data. The encoded data of the input frame image encoded by the first moving picture encoder/transmitter includes at least one packet data, each of which includes encoded frame prediction parameters and encoded compressed differential image data regarding an image area included in the input frame image. The second to nth motion picture encoders/transmitters encode an image area included in at least one packet encoded by the first motion picture encoder/transmitter at a compression rate equal to or higher than that of the first motion picture encoder/transmitter using a reference frame image used in inter prediction performed on the image area by the first motion picture encoder/transmitter, and transmit at least a part of the encoded packet data thus obtained to the motion picture transcoding/receiving apparatus. Other operational details are substantially the same as those of the fifth embodiment.

The arrangement and operation of the transcoding/receiving apparatus according to the sixth embodiment of the present invention are the same as those of the fourth embodiment, but different from those of the fifth embodiment.

(6.B) transcoding/transmitting means:

the arrangement and operation of the transcoding/transmitting apparatus according to the present embodiment are substantially the same as those of the transcoding/transmitting apparatus according to the fifth embodiment shown in fig. 9, except that only the operations of the first encoded packet generator 1105, the second encoded packet generator 1113, the first error-detecting code additional frame/packet number adder 1106, and the second error-detecting code additional frame/packet number adder 1114 are different. Differences from the fifth embodiment are explained below.

In the moving picture data transcoding/transmitting apparatus according to the present embodiment, the first encoded packet generator 1105 and the second encoded packet generator 1113 generate encoded packet data such that an image area included in the encoded packet data generated by the first encoded packet generator 1105 and an image area included in the encoded packet data generated by the second encoded packet generator 1113 are identical to each other.

The first error-detection-code-appended frame/packet number adder 1106 and the second error-detection-code-appended frame/packet number adder 1114 operate to add the same packet identification number to the encoded packet data corresponding to the same image in the same frame. If the packet data generated by the first and second packet generators includes the frame number and information specifying the position of the picture region included in the packet data, the frame/packet identification number is not added.

(6.C) advantages:

according to the sixth embodiment described above, the moving picture transcoding/transmitting apparatus decodes at least a part of the input moving picture data, encodes the same moving picture data into two encoded data, and transmits the encoded data with a time difference that is constant or adaptively changes.

The second motion picture transcoder/transmitter encodes an image area included in the packet encoded by the first motion picture transcoder/transmitter using the reference frame image used in encoding the frame with the first motion picture transcoder/transmitter. The transcoding/receiving apparatus side selects and outputs encoded data of good image quality having the lowest compression rate from the encoded data that has been normally received in units of packets.

As a result, even if a transmission path in which a high burst of frequent transmission errors and packet loss may occur and reliability is low is used, the possibility that both encoded data are erroneously transmitted is reduced, preventing the decoded image generated after data transmission from being seriously deteriorated.

By improving the compression rate of the second encoded data, the increase in the frequency band due to the transmission of the second encoded data can be reduced. Further, the first and second encoded data can be transmitted to a plurality of transmission paths having different frequency bands according to the condition of the transmission path and the intention of the moving picture transmitter or the moving picture receiver, and the influence of an error in the transmission path can be reduced.

(7) Seventh embodiment:

according to a seventh embodiment of the present invention, a transcoding/transmitting apparatus, wherein N represents an integer of 2 or more and M represents an integer of 1 or more, has:

(a) a first moving picture transcoder/transmitter for supplying the coded data packet data thereto and controlling transmission of the data by a predetermined transmission means;

(b) second to nth moving picture transcoders/transmitters for copying all packet data encoded by the first moving picture transcoder/transmitter or packets of packet data adaptively selected according to the nature of an inputted moving picture or a predetermined rule, and controlling at least a part of the resultant packet data to be transmitted with a constant or adaptively varying transmission time difference with the same or different transmission means as that used by the first moving picture transcoder/transmitter; and

(c) a mechanism for selecting the number of encoded data to be transmitted by the first to Nth moving picture transcoders/transmitters in accordance with the frequency bands which can be used by the first to Mth transmission paths, and transmitting the encoded data to the first to Mth transmission paths.

The transcoding/receiving apparatus side includes a selector for selecting at least one transmission path from the M transmission paths, receiving the N encoded data from the selected transmission path, and selecting and outputting the received encoded data packet data without transmission error or loss, for example, the encoded data packet data recorded normally first, from the encoded data packet generated by encoding the image in the same area in the same frame.

The seventh embodiment is explained in more detail below:

(7.A) overview:

fig. 12 shows the arrangement of a system according to a seventh embodiment of the invention. As shown in fig. 12, the system according to the seventh embodiment includes a transcoding/transmitting apparatus 1200 for moving picture data, a transcoding/receiving apparatus 1220, and a transmission path 1230 that transmits encoded data. The integer N represents the number of coded data transmitted by the transcoding/transmitting apparatus, and is an integer of 2 or more. The integer M represents the number of transmission paths 1230 for which N encoded data are transmitted, and is an integer of 1 or more.

The moving picture packet data is supplied to the transcoding/transmitting apparatus 1200, the transcoding/transmitting apparatus 1200 selects at least a portion of the moving picture packet data, and transmits the selected data to the first to mth transmission paths 1230.

As shown in fig. 12, the apparatus 1200 has first to nth moving picture transcoders/transmitters 1202 to 1205 for transmitting coded moving picture packet data to first to mth transmission paths. The moving picture data receiver 1201 receives moving picture packet data. The first moving picture transcoder/transmitter 1202 transmits at least one packet of the input moving picture packet data to the transcoding/receiving device 1220. The moving picture data duplicator 1203 duplicates the received packet and outputs the duplicated packet to the second to nth moving picture transcoders/transmitters 1204, 1205. The second to nth moving picture transcoders/transmitters 1204, 1205 transmit at least one duplicated data packet to the transcoding/receiving device 1220. Among the first to nth encoded moving picture data, encoded data selected according to a frequency band that can be used by a transmission path is transmitted to the first to mth transmission paths 1230.

In the moving picture transcoding/receiving apparatus 1220, the reception transmission path selector 1206 selects at least one transmission path from M transmission paths to which the transcoding/transmitting apparatus has transmitted encoded data. The moving picture transcoding/receiving means 1220 receives the N encoded data from the selected transmission path, and decodes and converts the received data.

As shown in fig. 12, the motion picture transcoding/receiving apparatus 1220 includes first to nth coded data receivers 1207 to 1209 for receiving coded data transmitted by the first to nth motion picture transcoders/transmitters 1202 to 1205 of the transcoding/transmitting apparatus 1200, and a coded data reconstructor 1210.

The coded data reconstructor 1210 selects and outputs data from the maximum N coded data received by the coded data receivers 1207 to 1209 without transmission error and loss. Since the maximum N encoded data have the same compression rate, the encoding reconstructor 1210 selects and outputs, for example, the first normally received encoded data.

(7.B) the transcoding/transmitting means:

fig. 13 shows a detailed arrangement of a moving picture transcoding/transmitting apparatus 1200 (see fig. 7) according to the seventh embodiment. For simplicity, it is assumed that the number N of encoded data output from the moving picture transcoding/transmitting apparatus is 3, and the number M of transmission paths for transmitting the encoded data is 2.

In fig. 13, a first transmission packet selector 1301 of the first moving picture transcoder/transmitter 1300 adaptively selects a packet to be transmitted from among input moving picture packet data according to the nature of an image and the condition of a transmission path. For example, the first transmission packet selector 1301 may select and transmit a packet every constant period (once every n packets). Alternatively, the first transmission packet selector 1301 refers to a characteristic parameter in a packet of the moving picture frame, and adaptively determines a selected and encoded packet to be transmitted. For example, the first transmission packet selector 1301 may refer to a parameter, e.g., a motion vector, which seriously affects the quality of a decoded image due to a bit or packet loss, as a characteristic parameter in an encoded packet, and adaptively determine the encoded packet to be transmitted. Alternatively, if the encoding process is an MPEG scheme, the first transmission packet selector 1301 may select a packet according to, for example, a rule (which may be dynamically changed) that requires selection of an I picture.

The first error-detecting code-attached frame/packet identification number adder 1302 adds an error-detecting code and a frame/packet identification number so that the receiving apparatus detects a transmission error and a packet loss of the output encoded packet.

In fig. 13, the packet duplicator 1303 of the second moving picture transcoder/transmitter 1310 duplicates the input encoded moving picture packet data.

The second transmission packet selector 1303 selects a packet of the same number or a different number from the adaptively transmitted packets in the first moving picture transcoder/transmitter according to the nature of the image and the condition of the transmission path. If packets of different numbers are to be selected, the second transmission packet selector 1304 may select them according to the relationship (rule) of characteristic parameters such as the motion vector and its threshold. Alternatively, if the encoding process is an MPEG scheme, the second transmission packet selector 1304 may select a packet according to, for example, a rule that an I picture must be selected.

The second error-detecting code-attached frame/packet identification number adder 1305 adds an error-detecting code and a frame/packet identification number so that the receiving apparatus detects a transmission error and a packet loss of the encoded packet data output from the selector 1304.

In the present embodiment, since M is 2 and N is 3, encoded moving picture data selected from the above-described first and second encoded moving picture data according to the frequency band that can be used by the transmission path can be transmitted to each of the two transmission paths.

The operation of the other processors than the above-described processor is the same as that of the fourth embodiment.

A preferred specific example of this embodiment is the same as that of the second embodiment. The arrangement and operation of the moving picture transcoding/receiving apparatus are the same as those of the fourth embodiment.

(7.C) advantages:

according to the seventh embodiment described above, the moving picture transcoding/transmitting apparatus converts the same moving picture packet data into two encoded data and transmits the encoded data with a time difference that is constant or adaptively changed.

The first moving picture transcoder/transmitter adaptively selects input moving picture packet data according to the property of a moving picture or a predetermined rule, and outputs the selected moving picture packet data. The second moving picture transcoder/transmitter copies the input moving picture packet data and selects and transmits at least a part of the copied moving picture packet data.

The transcoding/receiving apparatus side selects data without errors and losses from among normally received encoded packet data in units of packets, and selects data arriving first from among data received by, for example, two transmission paths, and outputs the selected data.

As a result, even if a transmission path with low reliability is used, which may cause frequent transmission errors and packet loss with high burstiness, the possibility that both encoded data are erroneously transmitted can be reduced, preventing the decoded image generated after data transmission from being seriously damaged.

By reducing the number of the selected second encoded data packet data, an increase in the transmission band due to the transmission of the second encoded data can be reduced.

(8) Eighth embodiment:

according to an eighth embodiment of the present invention, a transcoding/transmitting apparatus side, wherein N represents an integer of 2 or more and M represents an integer of 1 or more, has:

(a) a first moving picture transcoder/transmitter for supplying compressed encoded data packet data thereto, decoding at least a part of the inputted encoded data, performing compression encoding of the data at a compression rate equal to or higher than that of the inputted moving picture data, and controlling transmission of all frames or frames adaptively selected according to the property of the inputted moving picture or a predetermined rule using a predetermined transmission means;

(b) second to nth motion picture transcoders/transmitters for decoding at least a portion of input encoded data, performing compression encoding of the data at a compression rate equal to or higher than that of the first motion picture transcoder/transmitter, and controlling transmission of all frames of the resulting encoded data or frames adaptively selected according to a property of the input motion picture or a predetermined rule with the same or different transmission means as that used by the first motion picture transcoder/transmitter, with a transmission time difference that is constant or adaptively changed;

(c) a mechanism for selecting compression rates of the first to Nth moving picture transcoders/transmitters and/or the number of encoded data to be transmitted, in accordance with frequency bands which can be used by the first to Mth transmission paths, and transmitting the encoded data to the first to Mth transmission paths.

The transcoding/receiving apparatus side includes a selector for selecting at least one transmission path from the M transmission paths, receiving the N encoded data from the selected transmission path, extracting the received encoded data without transmission error or loss, and, for example, selecting and outputting encoded motion picture data of good image quality with the lowest compression rate from the encoded data in the simultaneous frames.

The eighth embodiment is described in more detail below:

(8.A) overview:

fig. 14 shows the arrangement of a system according to an eighth embodiment of the invention. As shown in fig. 14, the system includes a transcoding/transmitting apparatus 1400 of moving picture data, a transcoding/receiving apparatus 1420, and a transmission path 1430 for transmitting encoded data. The integer N represents the number of coded data transmitted by the transcoding/transmitting apparatus, and is an integer of 2 or more. The integer M represents the number of transmission paths for which N encoded data are transmitted, and is an integer of 1 or more.

The transcoding/transmitting apparatus 1400 decodes at least a part of the input encoded motion picture data, performs compression encoding processing of the resulting image at a compression rate equal to or higher than that of the input data, and transmits at least a part of the transcoded data to the motion picture transcoding/receiving apparatus. The transcoding/transmitting apparatus 1400 encodes the input moving picture data into N encoded data and transmits the encoded data as first to nth encoded moving picture data to the first to nth, N moving picture transcoders/transmitters 1403 to 1405.

The moving picture data receiver 1401 receives moving picture data. The moving picture decoder 1402 decodes at least a portion of the input encoded moving picture data. The first moving picture transcoder/transmitter 1403 performs a predetermined compression encoding process of the frame input to the transcoding/transmitting apparatus according to a predetermined compression processing procedure, and transmits at least a part of the encoded data thus obtained to the transcoding/receiving apparatus 1420. The second to nth motion picture transcoders/transmitters 1403 to 1405 encode the input frames at a compression rate equal to or higher than that of the first motion picture transcoder/transmitter 1403 and transmit at least a part of the encoded data thus obtained to the transcoding/receiving apparatus 1420. Encoded data selected according to a frequency band that can be used by a transmission path among the first to nth encoded moving picture data is transmitted to first to mth transmission paths 1430.

In the moving picture transcoding/receiving apparatus 1430, the reception transmission path selector 1406 selects at least one transmission path from M transmission paths for which the moving picture transcoding/transmitting apparatus has transmitted encoded data. The moving picture transcoding/receiving apparatus 1420 receives the N encoded data from the selected transmission path, and decodes and converts the received data.

As shown in fig. 14, the moving picture transcoding/receiving apparatus 1430 includes first to nth, N encoded data receivers 1407 to 1409 for receiving encoded data transmitted by the first to nth moving picture transcoders/transmitters 1403 to 1405 of the transcoding/transmitting apparatus 1400, and an encoded data reconstructor 1410.

The encoded data reconstructor 1410, for example, selects and outputs data of good image quality with the lowest compression rate from the maximum N encoded data that have been received by the encoded data receivers 1407 to 1409 without transmission errors and losses.

(8.B) the transcoding/transmitting means:

fig. 15 shows a detailed arrangement of a moving picture transcoding/transmitting apparatus 1400 according to the eighth embodiment of the present invention. For simplicity, it is assumed that the number N of encoded data output from the moving picture transcoding/transmitting apparatus is 2, and the number M of transmission paths for transmitting the encoded data is 2.

As shown in fig. 15, the decoder 1501 decodes at least a portion of input moving picture data. The first transmission frame/packet generator 1502 of the first motion picture transcoder/transmitter 1500, shown as the first motion picture transcoder/transmitter 1403 in fig. 14, encodes the decoded motion picture data at a compression rate equal to or higher than that of the input data, and outputs the encoded data to the first error detection code additional frame/packet identification number adder 1503. The first error detection code is added with the frame/packet identification number adder 1503 to add the error detection code and the frame/packet identification number so that the receiving apparatus can detect a transmission error and a packet loss of the coded packet data output from the first transmission frame/packet generator 1502. In this way, the first coded moving picture data is obtained and transmitted by the predetermined transmission means. Also, as shown in fig. 15, the second transmission frame/packet generator 1504 of the second motion picture transcoder/transmitter 1510, shown as the first motion picture transcoder/transmitter 1404 in fig. 14, encodes data at a rate equal to or higher than that of the first motion picture transcoder/transmitter 1500, and outputs the encoded data to the second error detection code additional frame/packet identification number adder 1505. The second error detection code-attached frame/packet identification number adder 1505 adds an error detection code and a frame/packet identification number so that the receiving apparatus can detect a transmission error and a packet loss of the coded packet data output from the second transmission frame/packet generator 1504. In this way, the second coded moving picture data is obtained and output by the predetermined transmission means.

In the present embodiment, since M is 2 and N is 2, the above-described first and second coded moving picture transcoding/transmission data is transmitted to each of the two transmission paths.

The operation of other processors than the above-described processor is the same as that of the third embodiment.

A preferred specific example of this embodiment is the same as that of the first embodiment. The arrangement and operation of the moving picture transcoding/receiving apparatus are the same as those of the third embodiment.

(8.C) advantages:

according to the present embodiment, the moving picture transcoding/transmitting apparatus decodes at least a part of the input moving picture data, encodes the same moving picture data into two encoded data, and transmits the encoded data with a time difference that is constant or adaptively changed.

The transcoding/receiving apparatus side selects and outputs encoded data of good image quality having the lowest compression rate from encoded data that has been normally received in units of frames.

As a result, even if a highly reliable transmission path in which frequent transmission errors and packet loss may occur with high burstiness is used, the possibility that both encoded data are erroneously transmitted is reduced, and a decoded image generated after data transmission is prevented from being seriously damaged.

Further, since at least one of the two encoded data selected by the moving picture transcoding/receiving apparatus is output to the moving picture decoding apparatus by the moving picture transcoding/receiving apparatus, the amount of calculation required by the moving picture decoding apparatus does not increase much compared to the general moving picture decoding apparatus.

(9) Ninth embodiment:

according to a ninth embodiment of the present invention, a transcoding/transmitting apparatus side, wherein N represents an integer of 2 or more and M represents an integer of 1 or more, has:

(a) a first moving picture transcoder/transmitter for supplying compressed encoded data packet data thereto, decoding at least a portion of the inputted encoded data packet data, performing compression encoding of at least a portion of the data at a compression rate equal to or higher than that of the inputted encoded data, and controlling transmission of all the packets or packets adaptively selected according to a property of the inputted moving picture or a predetermined rule using a predetermined transmission means;

(b) second to nth moving picture transcoders/transmitters for decoding at least a portion of the input coded packet data, performing compression coding of data into packet data at a compression rate equal to or higher than that of the first moving picture transcoder/transmitter, and controlling transmission of all the obtained packet data or packet data adaptively selected according to the properties of the input moving picture or a predetermined rule with a predetermined transmission means at a transmission time difference which is constant or adaptively varied;

(c) a mechanism for selecting compression rates of the first to Nth moving picture transcoders/transmitters and/or the number of encoded data to be transmitted according to frequency bands that can be used by the first to Mth transmission paths, and transmitting the encoded data to the first to Mth transmission paths.

The transcoding/receiving apparatus side includes a selector for selecting at least one transmission path from the M transmission paths, receiving the N encoded data from the selected transmission path, and, for example, selecting and outputting encoded data packet data of good image quality with the lowest compression rate from received packet data generated by encoding images in the same area of the same frame without transmission errors or losses.

The ninth embodiment is described in more detail below:

(9.A) overview:

the arrangement and operation according to the present embodiment are substantially the same as those according to the eighth embodiment. As shown in fig. 14, the system includes a moving picture transcoding/transmitting device, a transcoding/receiving device, and a transmission path for transmitting and transmitting encoded data. The integer N represents the number of coded data transmitted by the transcoding/transmitting apparatus, and is an integer of 2 or more. The integer M represents the number of transmission paths for which N encoded data are transmitted, and is an integer of 1 or more.

The moving picture transcoding/transmitting apparatus has substantially the same arrangement as that of the eighth embodiment, but the operation of the various constituent parts of the apparatus is slightly different. Only the differences from the eighth embodiment will be described below.

The moving picture transcoding/transmitting processor decodes at least a part of the input encoded moving picture data, performs a predetermined compression encoding process of the resulting image at a compression rate equal to or higher than that of the input image data, and transmits the transcoded data to the moving picture transcoding/receiving apparatus. The encoded data of the input frame image encoded by the moving picture transcoding/transmitting processor includes one or more packet data each including encoded interframe prediction parameters and encoded compressed differential image data regarding an image area included in the input frame image. The second to nth moving picture encoders/transmitters encode an image area included in at least one packet encoded by the first moving picture encoder/transmitter at a compression rate equal to or higher than that of the first moving picture encoder/transmitter, and transmit the resulting encoded packet data to the moving picture transcoding/receiving apparatus.

The moving picture transcoding/receiving apparatus has an arrangement substantially the same as that of the eighth embodiment, but the operation of the various constituent parts of the apparatus is slightly different. Only the differences from the eighth embodiment will be described below.

As in the case of the eighth embodiment, the coded data reconstructor 1410 selects, as coded data to be decoded, the data packet of good image quality having the lowest compression rate from the maximum N coded data packet data which are received by the first to nth coded data receivers without transmission errors or losses and include compressed data in the same area of the same frame. The coded data reconstructor 1410 performs selection on each packet data transmitted by the transcoding/transmitting apparatus.

(9.B) the transcoding/transmitting means:

the arrangement and operation of the moving picture transcoding/transmitting apparatus according to the present embodiment are substantially the same as those of the moving picture transcoding/transmitting apparatus according to the eighth embodiment shown in fig. 15, except that the operations of the first encoded data packet generator 1502, the second encoded data packet generator 1504, the first error-detection-code additional frame/packet number adder 1503, and the second error-detection-code additional frame/packet number adder 1505 are different. Only the differences are explained below.

In the moving picture data transcoding/transmitting apparatus according to the present embodiment, the first encoded packet generator 1502 and the second encoded packet generator 1504 generate encoded packet data such that an image area included in the encoded packet data generated by the first encoded packet generator 1502 and an image area included in the encoded packet data generated by the second encoded packet generator 1504 are identical to each other. A preferred specific example of the present embodiment described above is the same as that of the second embodiment described above. The arrangement and operation of the moving picture transcoding/receiving apparatus are the same as those of the fourth embodiment.

(9.C) advantages:

according to the ninth embodiment, a moving picture transcoding/transmitting apparatus decodes at least a part of input moving picture data, encodes the same moving picture data into two encoded data, and transmits the encoded data with a time difference that is constant or adaptively varies.

The second motion picture transcoder/transmitter encodes the image information included in the data packet encoded by the first motion picture transcoder/transmitter. The transcoding/transmitting apparatus side selects and outputs encoded data of good picture quality having the lowest compression rate from the normally received encoded data in units of packets.

In the present embodiment, the transcoding/transmitting apparatus and the transcoding/receiving apparatus are used in combination with each other. However, there is no problem if they are used independently of each other. The first to nth transcoded data may be transmitted in a staggered manner, rather than in an interval period manner. The first to nth transcoded data may be mixed in their sequence according to a crossover processing method so that the mth encoded data can be transmitted after the nth encoded data (m < N). The first to nth transcoded data may be multiplexed by a multiplexer and then transmitted, or may be transmitted in parallel with each other.

According to a modification of each of the above embodiments, delay adders 502, 503 or delay adders 506, 507 shown in fig. 5 for delaying the second to nth moving picture data from the second to nth moving picture transcoders/transmitters and multiplexers 504, 508 shown in fig. 5 for multiplexing the first encoded moving picture data output from the first moving picture transcoder/transmitter and the added delayed second to nth encoded moving picture data may be provided in the moving picture transcoding/transmitting apparatus. Alternatively, a delay adder may not be provided, but an arrangement of multiplexers 504, 508 may be provided in the motion picture transcoding/transmitting apparatus to interleave, multiplex, and output the first to nth encoded motion picture data from the first to nth motion picture transcoders/transmitters of the motion picture transcoding/transmitting apparatus. Each of the M transmit paths 130 (see fig. 1) may include the same or different communication media, e.g., wireless or wired media.

(10) Tenth embodiment:

another embodiment of the present invention is explained below. Fig. 16 shows a system arrangement of a tenth embodiment of the present invention. As shown in fig. 16, the system includes an encoding device 40 for outputting encoded data, a transcoding/transmitting device 10 for moving picture data, a plurality of (K) transcoding/receiving devices 201 to 20K for moving picture data, and a plurality of (K) decoding devices 301 to 30K connected to the transcoding/receiving devices 201 to 20K. Each device 40 serves as an information source for distributing the encoded data and comprises a known server device. The transcoding/transmitting apparatus 10 includes any of the transcoding/transmitting apparatuses according to the present invention described above according to the first to tenth embodiments, for example, the transcoding/transmitting apparatus 100 shown in fig. 1.

Each of the plurality of transcoding/receiving apparatuses 20 for moving picture data includes any of the transcoding/receiving apparatuses according to the present invention, for example, the transcoding/receiving apparatus 120 shown in fig. 1, which have been described according to the first to tenth embodiments. The decoding device 30 is a device (decoder) for decoding and displaying the encoded data from the transcoding/receiving device 20, and includes existing products.

In the embodiment shown in fig. 16, it will be used in the transcoding/transmitting apparatus 10 and the transcoding/receiving apparatus 20₁To 20_KA transmission path 130 for transmitting information therebetween is assigned to each transcoding receiving apparatus. That is, for the M transmission paths 130 in the embodiment shown in fig. 1, M is 1, and a plurality of transcoding/receiving apparatuses 120 shown in fig. 1 are provided. The transcoding/transmitting apparatus 10 has N moving picture transcoders/transmitters (not shown), and outputs N encoded data in the same manner as in each of the embodiments described above.

In a specific example of the present invention, the transcoding/transmitting apparatus 10 is connected to an internet communication network (not shown), and the encoding apparatus 40 inputs the encoded data transmitted according to, for example, UDP/IP protocol to the transcoding/transmitting apparatus 10. A moving picture transcoder/transmitter, not shown, of the transcoding/transmitting apparatus 10 performs a processing operation according to RTP (real-time transport protocol). The transcoding/receiving means 20 functions, for example, as a client terminal connected to an internet communication network.

If the transmission path in the present embodiment is wireless, the transcoded data output from the transcoding/transmitting apparatus 10 is supplied via UDP/IP protocol and one physical layer, and is transmitted via a base station in the mobile packet communication system network to a router or gateway, etc., and finally transmitted to the transcoding/receiving apparatus 20 as a destination. In the transcoding/receiving apparatus 20, the data that has been transcoded by the transcoding/transmitting apparatus 10 between the encoding apparatus 40 and the decoding apparatus 30 is reconstructed into encoded data corresponding to the original encoded data in the encoding apparatus 40. According to a process corresponding to the encoding process performed by the encoding device 40, the decoding device 30 decodes the encoded data and displays the moving picture on a display device, not shown. The decoding apparatus (decoder) 30 connected to the transcoding/receiving apparatus 20 may be provided as a terminal integrated with the transcoding/receiving apparatus 20 or provided in a terminal (personal computer) connected for communication with the terminal serving as the transcoding/receiving apparatus 20.

In the present embodiment, the code conversion/reception device 20 is arranged to output a control signal (request signal) to the code conversion/transmission device 10. In response to the control signal, the transcoding/transmitting apparatus 10 transmits the encoded data to the transcoding/receiving apparatus 10. Fig. 16 shows that the control signal is different from the encoded data output from the transcoding/transmitting apparatus 10.

Using the control signal transmitted from the transcoding/receiving apparatus 20 side to the transcoding/transmitting apparatus 10, it is possible to indicate system information of the transcoding/receiving apparatus 20, for example, an IP address, apparatus information, information on a coding scheme (e.g., ITU recommended h.261 or H263, or ISO/IEC recommended MPEG video) compatible with the decoding apparatus 30, and the like, to the transcoding/transmitting apparatus 10, thereby enabling the transcoding/transmitting apparatus 10 to perform encoding and converting processes matching the transcoding/receiving apparatus 20 and the decoding apparatus 30 in response to the request signal. The present invention can also be applied to a case where the transmission path is a wired communication path.

In the arrangement shown in fig. 16, a plurality of (N) encoded data respectively output from the code conversion/transmission apparatus 10 to the transmission path 13 may be separated by a time period by a delay adder and multiplexed by a multiplexer, as shown in fig. 5. Alternatively, the N encoded data may be interleaved by a multiplexer to be mixed in their sequence and sent as multiplexed output to the transmission path with a time difference. The delay adder and the multiplexer shown in fig. 5 may be provided in the transcoding/transmitting apparatus 10. In this case, the transcoding/transmitting apparatus 20 has a splitter 511 shown in fig. 5. The multiplexed transmission packet received from the transmission path selected by the reception transmission path selector is divided into packets corresponding to the encoded data, and the encoded data is extracted from the packets and reconstructed. According to this example, the code conversion/transmission apparatus 10 receives the coded data from the coding apparatus 40 as the information source, and the code conversion/transmission apparatus 10 converts the data into a form resistant to data loss and data errors on the transmission path 13 and transmits the data to the code conversion/reception apparatus 20 side. Thus, the encoded data may be transmitted in a manner suitable for transmission over the transmission path 13. The decoding device 30 performs a decoding process corresponding to the encoding process performed by the encoding device 40.

Although the invention has been described in connection with the above-described embodiments, the invention is not limited to the arrangements of the above-described embodiments, but various modifications and changes may be made by those skilled in the art without departing from the scope of the invention as specified in the patent claims.

Claims

1.A moving picture data transcoding/transmitting apparatus, comprising:

first to Mth transcoding/transmitting processors, wherein M is an integer of 1 or more, each transcoding/transmitting processor comprising:

(a) a first moving picture transcoder/transmitter for supplying thereto input compressed encoded data and outputting at least one frame of the input encoded data;

(b) a moving picture data decoder for decoding at least a portion of the input encoded data; and

(c) second to nth motion picture transcoders/transmitters, where N is an integer of 2 or more, which compressively encode data obtained by the motion picture data decoder at a compression rate equal to or higher than that of the first motion picture transcoder/transmitter and output at least one frame of the resulting encoded data, and in the case where N is an integer of 3 or more, which compressively encode at least one frame encoded by the first motion picture transcoder/transmitter at a compression rate equal to or higher than that of the second motion picture transcoder/transmitter using at least one of an inter-frame prediction parameter and prediction differential data obtained by performing inter-frame prediction on the frame by the second motion picture transcoder/transmitter, and outputting at least one frame of the resulting encoded data;

wherein the outputs of the first to Mth transcoding/transmitting processors are selectively transmitted to first to Mth transmission paths.

2.A moving picture data transcoding/transmitting apparatus, comprising:

(a) a first moving picture transcoder/transmitter for supplying thereto input compressed encoded packet data and outputting at least a part of the input encoded packet data;

(b) a moving picture data decoder for decoding at least a portion of the input coded data packet data; and

(c) second to Nth motion picture transcoders/transmitters, where N is an integer of 2 or more, which compressively encode data obtained by the motion picture data decoder at a compression rate equal to or higher than that of the first motion picture transcoder/transmitter and output at least a part of the resulting encoded data, and in the case where N is an integer of 3 or more, which compressively encode data packet data encoded by the second motion picture transcoder/transmitter at a compression rate equal to or higher than that of the second motion picture transcoder/transmitter using at least one of prediction differential data and inter-frame prediction parameters obtained by performing inter-frame prediction on an image area by the second motion picture transcoder/transmitter, and outputting at least a portion of the resulting encoded data;

3.A moving picture data transcoding/transmitting apparatus, comprising:

(a) a moving picture data decoder for decoding at least a portion of the input encoded data;

(b) a first moving picture transcoder/transmitter which encodes at least one frame of moving picture data generated by decoding the input encoded data by the moving picture data decoder, and outputs at least a part of the encoded data thus obtained; and

(c) second to nth moving picture transcoders/transmitters for re-encoding at least one frame encoded by said first moving picture transcoder/transmitter, using at least one of an interframe prediction parameter and prediction differential data obtained by performing interframe prediction on said frame by said first moving picture transcoder/transmitter, and outputting the encoded data thus obtained, wherein N is an integer of 2 or more;

4.A moving picture data transcoding/transmitting apparatus, comprising:

(a) a moving picture data decoder for decoding at least a portion of the input coded data packet data;

(b) a first moving picture transcoder/transmitter which re-encodes the data decoded by the moving picture data decoder and outputs at least a part of the encoded data packet data thus obtained; and

(c) second to nth moving picture transcoder/transmitter means for encoding an image area encoded by each of at least part of the packet data encoded by the first moving picture transcoder/transmitter, using at least one of an interframe prediction parameter and a prediction differential data obtained by interframe prediction performed on the image area by the first moving picture transcoder/transmitter, and outputting at least part of the encoded packet data thus obtained, where N is an integer of 2 or more;

5.A moving picture data transcoding/transmitting apparatus, comprising:

(a) a moving picture data decoder for decoding the input coded data packet data;

(b) a first moving picture transcoder/transmitter for encoding at least one frame of data decoded by the moving picture data decoder and outputting at least a part of the encoded data thus obtained; and

(c) second to nth motion picture transcoders/transmitters for encoding at least one frame encoded by said first motion picture transcoder/transmitter, using a reference frame image used in inter prediction performed on said frame by said first motion picture transcoder/transmitter, and outputting at least a part of the encoded data thus obtained, wherein N is an integer of 2 or more;

6.A moving picture data transcoding/transmitting apparatus, comprising:

(b) a first moving picture transcoder/transmitter which encodes at least a part of the data decoded by the moving picture data decoder and outputs at least a part of the encoded data packet data thus obtained; and

(c) second to nth moving picture transcoders/transmitters for encoding an image area encoded by each of said packet data of at least a part of the packet data encoded by said first moving picture transcoder/transmitter, using a reference frame image used in performing inter prediction on said image area by said first moving picture transcoder/transmitter, and outputting at least a part of the packet data thus obtained, where N is an integer of 2 or more;

7.A moving picture data transcoding/transmitting apparatus, comprising:

(a) a first moving picture transcoder/transmitter for supplying thereto inputted compression-encoded packet data and outputting at least one inputted packet;

(b) a moving picture data duplicator for duplicating at least one packet of packet data input by the first moving picture transcoding/transmitting means; and

(c) second to Nth moving picture code converter/transmitters which output at least a part of the packet data copied by the moving picture data copier with a time difference, wherein N is an integer of 2 or more;

8.A moving picture data transcoding/transmitting apparatus, comprising:

(b) a first moving picture transcoder/transmitter which outputs at least one frame generated by decoding data obtained by the coded moving picture data decoder; and

(c) second to Nth moving picture transcoder/transmitters for encoding the data generated by the moving picture data decoder and outputting at least one frame of the encoded data thus obtained, wherein N is an integer of 2 or more;

9.A moving picture data transcoding/transmitting apparatus, comprising:

(b) a first moving picture transcoder/transmitter which outputs at least one data packet generated by decoding the data obtained by the coded moving picture data decoder; and

(c) a second to Nth moving picture transcoder/transmitter for encoding data decoded by the moving picture data decoder and outputting at least a part of the packet data thus obtained, wherein N is an integer of 2 or more;

10. The transcoding/transmitting apparatus of any one of claims 1, 3, 5 and 8, wherein at least one of the first to nth motion picture transcoders/transmitters selects at least one frame according to a property of a motion picture or a predetermined rule.

11. The transcoding/transmitting apparatus of any one of claims 2, 4, 6, 7 and 9, wherein at least one of the first to nth motion picture transcoders/transmitters selects at least one packet according to a property of a motion picture or a predetermined rule.

12. The transcoding/transmitting apparatus of any one of claims 3 to 6, 8 and 9, wherein, when the first motion picture transcoder/transmitter encodes data obtained by decoding, the first motion picture transcoder/transmitter compresses data at a compression rate equal to or higher than that of the input encoded data.

13. The transcoding/transmitting apparatus of claim 1 or 2, wherein when the second to nth motion picture transcoders/transmitters encode data obtained by decoding, the second to nth motion picture transcoders/transmitters compress data at a compression rate equal to or higher than that of the input encoded data.

14. The transcoding/transmitting apparatus of any one of claims 3 to 6, 8 and 9, wherein, when the second to nth motion picture transcoders/transmitters encode data obtained by the decoding, the second to nth motion picture transcoders/transmitters compress the data at a compression rate equal to or higher than that of the first motion picture transcoder/transmitter.

15. The transcoding/transmitting apparatus of any one of claims 1 to 9, comprising means for controlling the outputs of the second to nth motion picture transcoders/transmitters and the output of the first motion picture transcoder/transmitter to be output with a time difference or to each of the first to nth motion picture transcoders/transmitters.

16. The transcoding/transmitting apparatus of claim 15, wherein the time difference for the outputs of the first to nth moving picture transcoders/transmitters is established according to the state of a transmission path and/or a predetermined rule.

17. The transcoding/transmitting apparatus according to any one of claims 1 to 9, comprising means for selecting compression rates of the first to nth motion picture transcoders/transmitters and/or the number of encoded data to be transmitted, according to frequency bands that can be used by the first to mth transmission paths, and transmitting data to the first to mth transmission paths.

18. Transcoding/transmitting device according to any of claims 1 to 9,

wherein outputs of the first to Mth transcoding/transmitting processors are transmitted to the first to Mth transmission paths, respectively.

19. The transcoding/transmitting apparatus according to any one of claims 1 to 9, comprising:

means for multiplexing and outputting first to nth encoded data outputs of the first to nth moving picture transcoders/transmitters of the first to mth transcoders/transmission processors in a time difference;

wherein the multiplexed outputs of the first to Mth transcoding/transmitting processors are transmitted to the first to Mth transmission paths, respectively.

20. The transcoding/transmitting apparatus of claim 19, wherein the time difference set for multiplexing the outputs of the first to nth moving picture transcoders/transmitters is set according to a state of a transmission path and/or a predetermined rule.

21. The transcoding/transmitting apparatus of any one of claims 1, 3, 5 and 8, wherein,

the moving picture data decoder is shared by a plurality of moving picture transcoders/transmitters of the first to nth moving picture transcoders/transmitters;

wherein the plurality of moving picture transcoders/transmitters encode the decoded data output from the moving picture data decoder when encoding the encoded data.

22. The transcoding/transmitting apparatus of any one of claims 2, 4, 6 and 9, wherein,

wherein each of the plurality of moving picture transcoders/transmitters encodes the packet data output from the moving picture data decoder when encoding the packet data.

23. A transcoding/receiving apparatus of moving picture data, comprising:

selection means for selecting a transmission path for receiving encoded data from first to Mth transmission paths, where M is an integer of 1 or more;

means for receiving encoded data from the transmission path selected by the selection means, and extracting the received encoded data having no transmission error and no loss; and

and a device for reconstructing the encoded data from the extracted encoded data and outputting the reconstructed encoded data.

24. The transcoding/receiving apparatus of claim 23, comprising means for selecting the encoded data in the same frame received from the selected transmission path according to compression rate and/or image quality.

25. A transcoding/receiving apparatus of moving picture data, comprising:

selection means for selecting a transmission path for receiving encoded data from first to Mth transmission paths, where M is an integer of 1 or more; and

means for receiving the encoded data from the transmission path selected by the selection means, extracting the received encoded data packet data having no transmission error and no loss; and

and a device for reconstructing the encoded data packet data from the extracted encoded data packet data and outputting the reconstructed encoded data packet data.

26. The transcoding/receiving apparatus of claim 25, comprising means for selecting packet data generated by encoding images in the same area of the same frame received from the selected transmission path according to a compression rate and/or image quality.

27. A transcoding/transmitting system of moving picture data, comprising the transcoding/transmitting apparatus according to any one of claims 1, 3, 5 and 8, and the transcoding/receiving apparatus according to claim 23 or 24.

28. The transcoding/transmitting system of claim 27, comprising means for controlling delay, multiplexing data, and outputting the multiplexed data so that the outputs of the first to nth motion picture transcoders/transmitters of the transcoding/transmitting apparatus can transmit the motion picture data with a time difference, wherein the multiplexed data is transmitted to the transmission path.

29. A transcoding/transmitting system of moving picture data, comprising a transcoding/transmitting apparatus according to any one of claims 2, 4, 6, 7 and 9, and a transcoding/receiving apparatus according to claim 25 or 26.

30. The transcoding/transmitting system of claim 29, comprising means for controlling delay, multiplexing data, and outputting the multiplexed data so that the outputs of the first to nth motion picture transcoders/transmitters of the transcoding/transmitting apparatus can transmit the motion picture data with a time difference, wherein the multiplexed data is transmitted to the transmission path.

31. The transcoding/transmitting system according to claim 28 or 30, wherein the time difference of the outputs of the first to nth moving picture transcoders/transmitters of the transcoding/transmitting apparatus of the moving picture data is established according to a state of a transmission path and/or a predetermined rule.

32. A transcoding/transmitting system of moving picture data, comprising:

encoding means for outputting encoded data;

the transcoding/transmitting apparatus according to any one of claims 1, 3, 5 and 8;

a plurality of transcoding/receiving devices according to claim 23 or 24; and

a plurality of decoding devices;

a transcoding/transmitting means in which the encoded data from the encoding means is input to the moving picture data;

providing an output from the transcoding/transmitting means of the moving picture data to the transcoding/receiving means of the plurality of moving picture data; and

the coded data from the transcoding/receiving means of the plurality of moving pictures is supplied to the plurality of decoding means and decoded.

33. The transcoding/transmitting system of claim 32, wherein said transcoding/transmitting means of the moving picture data transmits the encoded data to the transcoding/receiving means of the plurality of moving picture data in response to control signals respectively from the transcoding/receiving means of the plurality of moving picture data.

34. A transcoding/transmitting system of moving picture data, comprising:

encoding means for outputting encoded data;

the transcoding/transmitting apparatus according to any one of claims 2, 4, 6, 7 and 9;

a plurality of transcoding/receiving devices according to claim 25 or 26; and

a plurality of decoding devices;

the coded data from the transcoding/receiving means of the plurality of moving picture data is supplied to the plurality of decoding means and decoded.

35. The transcoding/transmitting system of claim 34, wherein said transcoding/transmitting means of the moving picture data transmits the encoded data to said transcoding/receiving means of the plurality of moving picture data in response to control signals respectively from said transcoding/receiving means of the plurality of moving picture data.

36. A transcoding/transmitting method of moving picture data, the method being performed by a transcoding/transmitting apparatus having first to mth transcoding/transmitting processors, where M is an integer of 1 or more, each transcoding/transmitting processor including first to nth moving picture transcoders/transmitters, and N is an integer of 2 or more, the method comprising the steps of:

(a) causing the input compressed encoded data to be provided to the first motion picture transcoder/transmitter and outputting at least one frame of the input encoded data;

(b) decoding at least a portion of the input encoded data;

(c) causing the second motion picture transcoder/transmitter to compression-encode data obtained by the motion picture data decoder at a compression rate equal to or higher than that of the first motion picture transcoder/transmitter and output at least one frame of the resulting encoded data, and in the case where N is an integer of 3 or more, the third to nth motion picture transcoders/transmitters use at least one of an inter prediction parameter and prediction differential data obtained by performing inter prediction on the frame by the second motion picture transcoder/transmitter to be equal to or higher than a compression rate of the second motion picture transcoder/transmitter, performing compression encoding on at least one frame encoded by the first moving picture transcoder/transmitter, and outputting at least one frame of the resulting encoded data; and

(d) selectively transmitting outputs of the first to Mth transcoding/transmitting processors to first to Mth transmission paths.

37. A transcoding/transmitting method of moving picture data, the method being performed by a transcoding/transmitting apparatus having first to mth transcoding/transmitting processors, where M is an integer of 1 or more, each transcoding/transmitting processor including first to nth moving picture transcoders/transmitters, and N is an integer of 2 or more, the method comprising the steps of:

(a) supplying the input compression-encoded packet data to the first moving picture transcoder/transmitter and outputting at least a portion of the input packet;

(b) decoding at least a portion of the input coded packet data;

(c) causing the second motion picture transcoder/transmitter to compression-encode the data obtained by the motion picture data decoder at a compression rate equal to or higher than that of the first motion picture transcoder/transmitter and output at least a part of the resulting encoded data, and in the case where N is an integer of 3 or more, the third to nth motion picture transcoders/transmitters use at least one of an inter prediction parameter and prediction differential data obtained by performing inter prediction on the image area by the second motion picture transcoder/transmitter to be equal to or higher than a compression rate of the second motion picture transcoder/transmitter, compressing and encoding the packet data encoded by the second moving picture transcoder/transmitter and outputting at least a part of the resultant encoded data; and

38. A transcoding/transmitting method of moving picture data, the method being performed by a transcoding/transmitting apparatus having first to mth transcoding/transmitting processors, where M is an integer of 1 or more, each transcoding/transmitting processor including first to nth moving picture transcoders/transmitters, and N is an integer of 2 or more, the method comprising the steps of:

(a) decoding at least a portion of the input encoded data;

(b) causing the first moving picture transcoder/transmitter to encode at least one frame of moving picture data generated by decoding, and to output at least a part of the encoded data thus obtained;

(c) causing the second to nth motion picture transcoders/transmitters to re-encode at least one frame encoded by the first motion picture transcoder/transmitter, using at least one of an interframe prediction parameter and prediction differential data obtained by performing interframe prediction on the frame by the first motion picture transcoder/transmitter, and outputting at least a portion of the encoded data thus obtained; and

39. A transcoding/transmitting method of moving picture data, the method being performed by a transcoding/transmitting apparatus having first to mth transcoding/transmitting processors, where M is an integer of 1 or more, each transcoding/transmitting processor including first to nth moving picture transcoders/transmitters, and N is an integer of 2 or more, the method comprising the steps of:

(a) decoding at least a portion of the input coded packet data;

(b) causing the first moving picture transcoder/transmitter to re-encode the data obtained by the decoding, and to output at least a part of the encoded data thus obtained;

(c) causing the second to nth moving picture transcoders/transmitters to encode an image area encoded by each of the packet data of at least a part of the packet data encoded by the first moving picture transcoder/transmitter, using at least one of an interframe prediction parameter and a prediction differential data obtained by interframe prediction performed on the image area by the first moving picture transcoder/transmitter, and outputting at least a part of the encoded packet data thus obtained; and

40. A transcoding/transmitting method of moving picture data, the method being performed by a transcoding/transmitting apparatus having first to mth transcoding/transmitting processors, where M is an integer of 1 or more, each transcoding/transmitting processor including first to nth moving picture transcoders/transmitters, and N is an integer of 2 or more, the method comprising the steps of:

(a) decoding input coded data packet data;

(b) causing the first moving picture transcoder/transmitter to encode at least one frame of data obtained by decoding, and to output at least a part of the encoded data thus obtained;

(c) causing the second to nth motion picture transcoders/transmitters to encode at least one frame encoded by the first motion picture transcoder/transmitter, utilizing a reference frame image used in performing inter-frame prediction on the frame by the first motion picture transcoder/transmitter, and outputting at least a part of the encoded data thus obtained; and

41. A transcoding/transmitting method of moving picture data, the method being performed by a transcoding/transmitting apparatus having first to mth transcoding/transmitting processors, where M is an integer of 1 or more, each transcoding/transmitting processor including first to nth moving picture transcoders/transmitters, and N is an integer of 2 or more, the method comprising the steps of:

(a) decoding input coded data packet data;

(b) causing the first moving picture transcoder/transmitter to encode data obtained by the decoding, and to output at least a part of the encoded data packet data thus obtained;

(c) causing the second to nth motion picture transcoders/transmitters to encode an image area of the packet data encoded by each of at least a portion of the packet data encoded by the first motion picture transcoder/transmitter, using a reference frame image used in inter prediction performed by the first motion picture transcoder/transmitter on the image area, and outputting at least a portion of the packet data thus obtained; and

42. A transcoding/transmitting method of moving picture data, the method being performed by a transcoding/transmitting apparatus having first to mth transcoding/transmitting processors, where M is an integer of 1 or more, each transcoding/transmitting processor including first to nth moving picture transcoders/transmitters, and N is an integer of 2 or more, the method comprising the steps of:

(b) copying at least one packet of packet data input by the first moving picture transcoding/transmitting means;

(c) causing the second to nth moving picture transcoders/transmitters to output at least a portion of the packet data obtained by the copying with a time difference; and

43. A transcoding/transmitting method of moving picture data, the method being performed by a transcoding/transmitting apparatus having first to mth transcoding/transmitting processors, where M is an integer of 1 or more, each transcoding/transmitting processor including first to nth moving picture transcoders/transmitters, and N is an integer of 2 or more, the method comprising the steps of:

(a) decoding at least a portion of the input encoded data;

(b) causing the first moving picture transcoder/transmitter to output at least one frame generated by encoding-decoding the resultant data;

(c) causing the second to nth moving picture transcoders/transmitters to encode the decoded data and to output at least one frame of the encoded data thus obtained; and

44. A transcoding/transmitting method of moving picture data, the method being performed by a transcoding/transmitting apparatus having first to mth transcoding/transmitting processors, where M is an integer of 1 or more, each transcoding/transmitting processor including first to nth moving picture transcoders/transmitters, and N is an integer of 2 or more, the method comprising the steps of:

(a) decoding at least a portion of the input coded packet data;

(b) causing the first moving picture transcoder/transmitter to output at least one data packet generated by encoding and decoding the resultant data;

(c) causing the second to nth moving picture transcoders/transmitters to encode data produced by the decoding and to output at least a part of the packet data thus obtained; and

45. The transcoding/transmitting method of any one of claims 36, 38, 40 and 43, wherein at least one frame is selected according to a property of the moving picture or a predetermined rule.

46. The transcoding/transmitting method of any one of claims 37, 39, 41, 42 and 44, wherein the at least one packet is selected according to a property of the moving picture or a predetermined rule.

47. The transcoding/transmitting method of any of claims 38 to 44, wherein, in the step (a), when the first motion picture transcoder/transmitter encodes the decoded data, the first motion picture transcoder/transmitter compresses the data at a compression rate equal to or higher than that of the input encoded data.

48. The transcoding/transmitting method of claim 36 or 37, wherein in the step (c), when the second to nth motion picture transcoders/transmitters encode the decoded data, the second to nth motion picture transcoders/transmitters compress the data at a compression rate equal to or higher than that of the input encoded data.

49. The transcoding/transmitting method of any of claims 38 to 42, wherein in the step (c), when the second to Nth motion picture transcoders/transmitters encode the decoded data, the second to Nth motion picture transcoders/transmitters compress the data at a compression rate equal to or higher than that of the second to Nth motion picture transcoders/transmitters.

50. The transcoding/transmitting method of any one of claims 33, 35 to 42, wherein the outputs of the second to Nth moving picture transcoders/transmitters in the step (c) and the output in the step (a) are output with a time difference, and/or the corresponding outputs in the step (c) are output with a time difference.

51. The transcoding/transmitting method of claim 50, wherein a time difference for outputs of the first to Nth moving picture transcoders/transmitters is established according to a state of a transmission path and/or a predetermined rule.

52. The transcoding/transmitting method of any of claims 33 and 35 to 42, wherein compression rates of the first to Nth moving picture transcoders/transmitters and/or the number of encoded data to be transmitted are selected according to frequency bands that can be used by the first to Mth transmission paths, and data is transmitted to the first to Mth transmission paths.

53. The transcoding/transmitting method according to any one of claims 36 to 41, 43 and 44, wherein data obtained by decoding in the common moving picture decoding apparatus is supplied to a plurality of moving picture transcoders/transmitters of the first to nth moving picture transcoders/transmitters for encoding data generated by decoding moving picture data.

54. A transcoding/receiving method of moving picture data, comprising the steps of:

selecting at least one transmission path from M transmission paths, wherein M is an integer of 1 or more than 1; and

receiving the encoded data from the selected transmission path, extracting the received encoded data without transmission error and loss, and reconstructing the encoded data from the extracted encoded data and outputting the reconstructed encoded data.

55. The transcoding/receiving method of claim 54, wherein if a plurality of encoded data in the same frame are received, one encoded data is selected according to a compression rate and/or an image quality.

56. A transcoding/receiving method of moving picture data, comprising the steps of:

receiving encoded data from the selected transmission path, extracting the received encoded transmission error and lost encoded packet data, and reconstructing the encoded packet data from the extracted encoded packet data and outputting the reconstructed encoded packet data.

57. The transcoding/receiving method of claim 56, wherein if a plurality of packet data generated by encoding images in the same area of the same frame are received, one packet data is selected according to a compression rate and/or image quality.

58. A transcoding method of moving picture data, comprising the steps of receiving encoded data transmitted according to the transcoding/transmitting method of any one of claims 36, 38, 40 and 43, according to the transcoding/receiving method of claim 54 or 55.

59. A transcoding method of moving picture data, comprising the steps of receiving encoded data transmitted according to the transcoding/transmitting method of any one of claims 37, 39, 41, 42 and 44, according to the transcoding/receiving method of claim 55 or 57.

60. A transcoding/transmitting apparatus for supplying encoded data thereto and outputting the encoded data to a transmission path, comprising:

a plurality of transcoding/transmitting means for outputting the inputted encoded data and the encoded data generated by re-encoding the inputted encoded data, or outputting a plurality of encoded data including the encoded data generated by re-encoding the inputted encoded data, respectively;

wherein said plurality of transcoding/transmitting means outputs at least a part of said input encoded data and/or said re-encoded data, and transmits said plurality of encoded data to one transmission path or a plurality of transmission paths.

61. The transcoding/transmitting apparatus of claim 60, wherein one of the plurality of transcoding/transmitting means encodes data at a compression rate equal to or higher than that in the compression encoding of the other transcoding/transmitting means.

62. A transcoding/receiving apparatus for receiving encoded data transmitted from the transcoding/transmitting apparatus as claimed in claim 60 or 61 to a transmission path, comprising:

means for selecting a transmission path for receiving data from the transmission path or the plurality of transmission paths; and

means for receiving encoded data from said selected transmission path and reconstructing the encoded data from the normally received encoded data.

63. A code transmission system comprising:

transcoding/transmitting device according to claim 60 or 61; and

at least one transcoding/receiving apparatus according to claim 62;

wherein the transcoding/transmitting apparatus receives the encoded data transmitted from the device for distributing encoded data, and outputs the encoded data generated by transcoding of the received encoded data;

the transcoding/receiving means receives the encoded data output from the transcoding/transmitting apparatus.