JP2002152307A - Data receiving device, data transmitting device, data communication system, data receiving method, data transmitting method, data communication method, and program storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a system which is capable of designating the format of the encoded data to transmit or receive and carrying out parallel decoding. SOLUTION: Format information which can be encoded by a data transmitting end is sent to a data receiving device from a data transmitting device, the data receiving device outputs a request to send data whose format is designated on the basis of a decoding format that can be carried out by the receiving device, and the encoded data conforming to the designated format on the basis of the request to send data are sent to the receiving device. Resultantly, even if either a hardware resource or a software resource is carrying out a decoding operation, a request to send data can be made, designating a format that carries out decoding by the use of the other resource, and an efficient data receiving/ decoding operation of executing the functions of both a software and a hardware in parallel can be realized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a data receiving apparatus,
The present invention relates to a data transmission device, a data communication system, a data reception method, a data transmission method, and a program storage medium. More specifically, a data receiving device, a data transmitting device, a data communication system, a data receiving method, a data transmitting method, and a program that enable efficient data transfer and data decoding by operating a plurality of decoding processes in parallel It relates to a storage medium.

[0002]

2. Description of the Related Art Currently, various data transfers are performed via various communication media such as Internet communication.
In recent years, transfer of image data, particularly moving image data, via a network has been actively performed. image data,
In particular, in general, moving image data is subjected to a process of reducing the data amount by encoding (compression) processing on the transmission side and executing decoding (decompression) processing on the reception side to reproduce the video data.

[0003] Transmission of moving images and audio over a network has become a common network application. In particular, by connecting a personal computer (PC) to a network, downloading and playing back a favorite compressed moving image from the WWW (World Wide Web),
It is possible to watch live video in real time. Among them, as a compression format of moving images, for example, MPEG1 to which decoding processing by software is applied is usually applied.
(Moving Pictures Experts Group 2), QuickTime (Apple trademark) and Real Player (Real Networks trademark), which can be soft-decoded, to MPEG2 (Moving Pictures Experts Group 2)
However, at present, there are various things that require decoding by hardware. In such a situation, the user prepares a plurality of types of hardware or software programs as decoders corresponding to each format in a reproduction device such as a PC, and selects and uses them as appropriate.

The most well-known method of image compression processing, M
PEG2 data is composed of hardware MPEG
It is decoded by two decoders. But M
Most PEG2 decoders can decode only a pair of video and audio programs at the same time.

When bidirectional image transmission of MPEG2 data is performed via a network, it is difficult to transmit MPEG2 wideband data over a plurality of pairs of programs. Therefore, in an application such as a videophone via a network, when a connection request for requesting image transmission is issued from another terminal via the network while using the MPEG2 decoder, one of the transmitting terminals receives the request. There was a problem that only images could be viewed.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has the resources (the presence or absence of the MPEG2 decoder and the CPU processing capability) and the usable format (Real Play) between the transmitting and receiving terminals.
er, MPEG2, etc.) via a network, and when parallel decoding is possible, decoding is executed in parallel to realize a system capable of efficient data processing. Aim.

[0007]

SUMMARY OF THE INVENTION A first aspect of the present invention is as follows.
In the data receiving device, receiving the transmittable encoding format information of the data transmitting device, based on the decoding processing function executable in the data receiving device, the selected format information selected from the encoding format information, the data transmitting device Characterized in that the data receiving apparatus has a configuration for executing a process of transmitting a coded data transmission request to the request.

Further, in one embodiment of the data receiving apparatus of the present invention, the data receiving apparatus includes a decoding unit for decoding encoded data by hardware and a control unit for executing decoding processing of encoded data by software. And having a configuration capable of executing both decoding processes in parallel, determining whether or not the decoding process is performed by each function of hardware and software, and issuing an encoded data transmission request specifying a processable format. It is characterized by having a configuration for executing processing for transmitting to a data transmitting apparatus.

Further, in one embodiment of the data receiving apparatus according to the present invention, the transmittable encoding format information of the data transmitting apparatus is a format list listing encoding processing formats possessed as functions of the data transmitting apparatus. And a resource list listing usage information of encoding processing resources of the data transmitting apparatus.

[0010] Further, in one embodiment of the data receiving apparatus of the present invention, the data receiving apparatus comprises a display means for displaying encoding format information received from the data transmitting apparatus, and an encoding means displayed on the display means. Input means for inputting format selection information designated as a reception format from the format information.

[0011] Further, a second aspect of the present invention is a data transmitting apparatus, which transmits, to a data receiving apparatus, encoding format information that can be transmitted by the data transmitting apparatus, and a format for receiving from the data receiving apparatus. There is provided a data transmitting apparatus having a configuration for executing processing for transmitting encoded data based on a specified format based on a specified encoded data transmission request.

Further, in one embodiment of the data transmitting apparatus according to the present invention, the data transmitting apparatus includes, as the encoding format information, a format list listing encoding processing formats possessed as functions of the data transmitting apparatus. And a resource list listing usage information of encoding processing resources of the data transmitting apparatus.

Further, in one embodiment of the data transmitting apparatus according to the present invention, the data transmitting apparatus has a data encoding processing unit using hardware and a control unit executing data encoding processing using software. , Detecting the execution status of the encoding process by each function of hardware and software, and generating a resource list listing usage status information of encoding process resources of the data transmitting apparatus. .

Further, a third aspect of the present invention is a communication system for transmitting and receiving encoded data, the data transmitting apparatus having an encoding processing function using a plurality of formats,
Having a data receiving device having a decoding processing function by a plurality of formats, the data transmitting device transmits to the data receiving device encoding format information that can be transmitted by the data transmitting device, and from the data receiving device Based on an encoded data transmission request specifying a format to be received, the data receiving apparatus has a configuration for executing processing for transmitting encoded data based on the specified format, and the data receiving apparatus is capable of transmitting the encoded format information of the data transmitting apparatus. And transmitting a selected format information selected from the encoded format information as an encoded data transmission request to the data transmitting device based on a decoding process function executable in the data receiving device. A communication system characterized in that:

Further, a fourth aspect of the present invention provides a data receiving method, comprising the steps of: receiving a transmittable encoding format information of a data transmitting apparatus; and a decoding processing function executable by the data receiving apparatus. Transmitting a selected format information selected from the encoded format information as an encoded data transmission request to the data transmitting apparatus.

Further, in one embodiment of the data receiving method of the present invention, the data receiving method further includes a step of determining whether or not a decoding process is performed by hardware and software functions of the data receiving device. Transmitting an encoded data transmission request specifying a possible format to the data transmission device.

Further, in one embodiment of the data receiving method of the present invention, the data receiving method further includes a display step of displaying encoding format information received from the data transmitting apparatus, and a code displayed in the display step. Inputting format selection information designated as a reception format from the formatted format information.

Further, according to a fifth aspect of the present invention, in the data transmission method, a step of transmitting, to the data receiving apparatus, encoding format information that can be transmitted by the data transmitting apparatus, and receiving from the data receiving apparatus. Transmitting encoded data based on the specified format based on the encoded data transmission request specifying the format.

Further, in one embodiment of the data transmission method according to the present invention, execution of the encoding process by each function of a data encoding unit by hardware and a control unit to execute data encoding process by software. 13. The data transmission method according to claim 12, further comprising: detecting a status; and generating a resource list listing usage status information of encoding processing resources of the data transmission device.

Further, a sixth aspect of the present invention is a data communication method for transmitting and receiving encoded data, wherein the data transmitting apparatus transmits, to the data receiving apparatus, encoding format information that can be transmitted by the data transmitting apparatus. Transmitting, and in the data receiving device, receiving the encoding format information, and transmitting to the data transmitting device an encoded data transmission request specifying the selected format selected based on the decoding processing function executable in the data receiving device. And transmitting the encoded data based on the specified format based on the format-specified encoded data transmission request received from the data receiving device in the data transmitting device. Data communication method.

Further, a seventh aspect of the present invention is a program storage medium for providing a computer program for executing a data receiving process on a computer system, wherein the computer program is capable of being transmitted by a data transmitting device. And transmitting the selected format information selected from the encoded format information as an encoded data transmission request to the data transmission device based on the step of receiving the encoded format information and the decoding processing function executable in the data reception device. And a program storage medium.

Further, an eighth aspect of the present invention is a program storage medium for providing a computer program for causing a data transmission process to be executed on a computer system, wherein the computer program is capable of being transmitted by a data transmission device. Transmitting encoded data to the data receiving device, and transmitting encoded data based on the specified format based on a format-specified encoded data transmission request received from the data receiving device, A program storage medium characterized by having:

[0023]

According to the above arrangement, even if it is necessary to decode another program in response to another connection request while using an MPEG2 decoder which can decode only a pair of video and audio programs, it is possible to perform reception while receiving. It is possible to selectively and simultaneously browse images of a plurality of programs at a desired image quality of a user on the receiving terminal side, for example, by assigning an image to a software decoder and a new channel to an MPEG2 decoder. In addition, the use of an MPEG2 decoder only when a high resolution is required, and a soft decoding at a low bit rate when a low resolution is sufficient, by a method of appropriately reselecting a format according to the image quality required in the scene. This also has the effect of saving network resources.

The program storage medium according to the seventh and eighth aspects of the present invention provides, for example, a computer program in a computer-readable format to a general-purpose computer system capable of executing various program codes. It is a medium to do.

Such a program storage medium defines a structural or functional cooperative relationship between the computer program and the storage medium in order to realize a predetermined computer program function on a computer system. Things. In other words, by installing the computer program into the computer system via the storage medium, a cooperative operation is exerted on the computer system, and the same operation and effect as the other aspects of the present invention can be obtained. You can do it.

Still other objects, features and advantages of the present invention are:
It will become apparent from the following more detailed description based on the embodiments of the present invention and the accompanying drawings.

[0027]

FIG. 1 shows a transmitting terminal for transmitting encoded data such as compressed data and a receiving terminal for receiving encoded data.
The conceptual diagram connected by the network is shown.

The transmitting terminal A21, the transmitting terminal B22, and the transmitting terminal C23 transmit data encoded in various formats such as MPEG1 and MPEG2 to the receiving terminal 11 via a network such as the Internet. . The receiving terminal interprets the encoding format, executes decoding by hardware or software according to the format, and reproduces the data.

In the transmission of encoded data via a network, when real-time processing is required, as in the case of image data and music data, uninterrupted supply of data is emphasized.
protocol (e.g., UDP) that does not perform retransmission processing is rarely used.
agram Protocol) is used. However, it is also possible to transmit and receive using TCP.

UDP is designed to allow an application process to transfer data to another application process on a remote machine with minimal overhead. Therefore, the information included in the UDP header is only the source port number, the destination port number, the data length, and the checksum.
There is no data field for identifying the packet order, such as a protocol (ntrol protocol).

In view of this, a real-time transport protocol: RTP (Re-
al-time Transport Protocol) is used. RTP is located in the transport layer and is generally used over UDP.

FIG. 2 shows the details of the RTP header in the structure of an IP packet obtained by packetizing the MPEG transport stream by RTP, UDP, and IP. The RTP header includes a version number (v), padding (P), presence or absence of an extension header (X), and the number of transmission sources (CRSC: Contributor).
ting Source), marker information (M), payload type, sequence number, RTP time stamp, synchronous source identifier, and contributing source (CSRC) identifier. The processing time is controlled when the RTP packet is expanded by the time stamp added to the RTP header, and the real-time image or audio reproduction control can be performed. As shown in FIG. 2, the MPEG transport stream as compressed data is
A plurality is stored in the IP packet.

FIG. 3 shows details of a UDP (User Datagram Protocol) header in an IP packet obtained by packetizing an MPEG transport stream by RTP, UDP, and IP. UDP is a protocol that provides a connectionless service, and has a simple header configuration. As shown in the figure, the UDP header has a source port number, a destination port number, a header indicating the data length, and a length indicating the total number of bytes of the data length. It has a checksum as a reliability guarantee value of the UDP packet. Since the UDP has such a simple configuration, control is simplified.

FIG. 4 shows details of the IP header in the structure of an IP packet obtained by packetizing the MPEG transport stream using RTP, UDP (TCP), and IP. TOS that stores a version indicating a version of IPv4, IPv6, etc., a header length, and priority information
(Type of Service) field, packet length, packet identifier, flag as control information on data division (fragment) in the IP layer, fragment offset indicating the location of the divided (fragmented) data, and until data is discarded TTL (Time to Liv)
e), protocol used in upper layer (4: IP, TC
P: 7, UDP: 17 ...), a checksum of the header, a source IP address, and a destination IP address.

FIG. 5 is a block diagram illustrating a configuration example of the data transmitting / receiving apparatus. In the present embodiment, the data to be transmitted and received is encoded data that can be encoded (decoded) and decoded (decoded) by software such as MPEG1, and encoded (decoded) and decoded (decoded) by dedicated hardware. Is MPEG2 (Moving Pictures Experts Group) format data which is a format for executing Hardware encoding,
Although an example in which MPEG2 is applied as decoding target data will be described, another compression method, for example, MPEG4 may be used.

In this embodiment, data compressed by MPEG2 is transmitted and received as IP packets via a network. Therefore, the data transmitting side executes packet generation (packetizing processing), and the data receiving side executes packet expansion (depacketizing processing).

The data transmitting / receiving apparatus of the present invention shown in FIG. 5 (ex.
PC) 31 executes MPEG2 compression / decompression and generates and decompresses packets by MPEG2 encoding and decoding; MPEG codec 101 which is hardware dedicated to decoding; network interface 102 functioning as an interface with a communication network;
7, an input / output interface 103 with input devices such as a keyboard 36, an AV interface 104 for inputting / outputting data from AV data input / output devices such as a video camera 33, a microphone 34, and a speaker 35, and a data output interface to the display 32. display·
An interface 105, data input / output interfaces, an MPEG codec 101, a CPU 106 for executing data transfer control between the network interface 102 and other various program controls, storage of various programs controlled and executed by the CPU 106, storage of data,
RAM and RO functioning as a work area of PU 106
And a HDD 107 as a storage medium for storing data and programs.
It is connected to the CI bus 109 and has a configuration that allows mutual data transmission and reception.

As shown in FIG. 5, the MPEG codec 101 receives, for example, image data from the video camera 33 and audio data from the microphone 34, and performs MPEG2 compression processing, encoding and multiplexing processing, and packet generation processing (packetizing). And finally generate an IP packet storing MPEG transport stream (TS) data. The generated IP packet is output on the PCI bus 109, output to the network via the network interface 102, and delivered to the destination address set in the header of the IP packet.

Further, under the control of the CPU 106 in accordance with a software encoding program such as MPEG1 stored in the HDD 108 or the memory 107, the image data from the video camera 33 and the audio data from the microphone 34 are encoded, and Is also executed.

The encoding process by the MPEG codec 101 and the software encoding process under the control of the CPU 106 can be executed in parallel.

On the other hand, the IP input via the network
The packetized MPEG transport stream (TS) data is transmitted to the network interface 102.
Is output on the bus 106 via the bus and input to the MPEG codec 101. The MPEG codec 101 executes a packet decompression process (depacketizing) of the input data, extracts the MPEG compressed data, executes a decoding process, and reproduces and outputs the data on the display 32 and the speaker 35.

FIG. 6 shows the configuration of the MPEG codec 101 having a hardware configuration. The moving image data input from the video camera 33 is an MPEG2 video encoder 2
01 is input. MPEG2 video encoder 201
Generates an MPEG video stream based on input moving image data. The audio data input from the microphone 12 is input to the MPEG audio encoder 202. The MPEG audio encoder 202 generates an MPEG audio stream based on the input audio data.

MPEG2 video encoder 201, MP
The EG audio encoder 202 and these two streams are input to an MPEG multiplexer 203 and multiplexed as an MPEG2 transport stream. The transport stream (TS) is a packet stream each divided into a predetermined data amount, and L
A plurality of MPEG-TS packets (see FIG. 2) are included in an IP packet output from a network such as an AN.

The MPEG2 transport stream generated by the MPEG multiplexer 203 further includes an RT
In the P packet generating means 204, an RTP packet is generated by adding an RTP header to the MPEG2 transport stream, and a UDP (User Datagram Pr
otocol) A packet generating means 205 adds a UDP header to the RTP packet to generate a UDP packet, and an IP packet generating means 206
An IP packet is generated by adding an IP header to the DP packet, output to the PCI bus 109 via the PCI interface 207, and output to the network from the network interface 102 shown in FIG.

As described above, the I output on the network
The P packet is input to the MPEG codec via the network interface 102 and the PCI bus 106 at the receiving side terminal, and is input from the PCI interface 207 to the IP packet expansion unit 208 to expand the IP packet, that is, the packet according to the IP header information. Expansion processing is executed, and UDP packet expansion processing is executed by the UDP packet expansion unit 209. Finally, the RTP
The MPEG2 transport stream is extracted by the packet expansion unit 210 by expansion processing according to the RTP header. The RTP packet has a time stamp as described later, and delay fluctuations in the network transfer, an arrival order, and the like are corrected and absorbed based on the time stamp.

The extracted MPEG2 transport stream is separated into an MPEG video stream and an MPEG audio stream by an MPEG demultiplexer 211, and a decoding process is executed by an MPEG video decoder 212 and an MPEG audio decoder 213, respectively. , Speaker 3
5 is played.

The network interface 102
MPEG1 and other software-decodable encoded data input through the HDD 108 or the memory 10
7, a decoding process is executed under the control of the CPU 106 according to a software decoding program such as MPEG1 stored in the
5 is played.

The decoding process by the MPEG codec 101 and the software decoding process under the control of the CPU 106 can be executed in parallel.

In the system of the present invention, in order to execute the above-described hardware decoding processing and software decoding processing, an inquiry processing as to whether or not processing of received data is possible between terminals transmitting and receiving encoded data via a network. And execute notification processing.

FIG. 7 shows a processing sequence diagram performed between terminals that execute transmission and reception of encoded data. The data transmission side terminal uses MPEG2, which requires hardware decoding,
There is a possibility of transmitting various encoded data such as MPEG1 which can perform software decoding.

First, the data transmitting terminal issues a transmission request to the receiving terminal, and notifies that data transmission is to be performed. The receiving terminal that has received the transmission request includes a transmission format list listing encoding formats executable by the transmitting terminal, a codec of the transmitting terminal, and a CP.
Based on the status of resources such as U, a resource list indicating a format that can be actually executed is requested from the transmission side.

The data transmitting side transmits the transmission format list and the resource list to the receiving terminal in response to the list request.

FIG. 8 shows an example of the transmission format list. The format list is a list of encoding formats that the data transmitting terminal has as functions.
In the example of FIG. 8, in addition to the format type, a stream format, a profile, a level, a mode of audio data, and the like are included as additional information. The format type is a mandatory item, but other items are added as necessary.
For example, in software encoding, decoding, and the like, the version information of the program is also included in the list as necessary. That is, it is necessary for the data receiving side to have sufficient data to determine whether or not encoded data can be decoded in the format defined in the list.

FIG. 9 shows an example of the transmission resource list. The resource list is a list of resources such as a CPU and hardware of the data transmitting terminal and a use state. In the example of FIG. 9, a network 1 capable of transferring at a maximum bit rate of 100 Mbps is used as a resource.
Is at 15% usage rate. Also, the encoded data by the MPEG2 encoding is available at 5 Mbps, currently has a usage rate of 0%, and is not used.
Also, it is recorded that the encoded data by the MPEG1 encoding is available at 1.5 Mbps, the usage rate is currently 0%, and the data is not used. The list in FIG. 9 is one example, and the data receiving side may be configured as a list including other items as long as the data receiving side is configured as data that can grasp the current situation in which encoded data can be transmitted on the data transmitting side. Good.

The resource list shown in FIG. 9 is obtained by the resource use condition detection program of the data transmission device, by which the data is encoded by the hardware and by the control unit which executes the data encoding by the software. The execution status is periodically detected, generated based on the detection result, and sequentially updated based on a change in the resource usage status.

Returning to FIG. 7, the processing sequence between the data transmitting terminal and the receiving terminal will be further described.

The receiving terminal that has received the transmission format list and the transmission resource list generates a transmission request to the receiving user through the display I / F 105 in FIG. 5 and information related to the terminal that transmitted the transmission request. (Sending terminal user name) and a message prompting selection of a desired receiving format and resource are displayed on the display 3.
2 is displayed. When the user's selection result is input by the input / output I / F 103 in FIG. 5, the receiving terminal transmits the selection result to the transmitting terminal as a reception format and a resource request.

The user selects a format that can be transmitted by the transmitting terminal and that can be decoded by the terminal based on the list, and transmits a transmission request to which the data indicating the selected format is added to the transmitting terminal. I do. This transmission request may be executed by adding a selection identifier to the received transmission format list and transmission resource list and returning the transmission format list and the transmission resource list to the transmitting terminal.

The receiving terminal periodically executes a process of detecting the execution status of the decoding process by each of the hardware and software functions, and uses one of the processes when one of the processes is being executed. A configuration may be adopted in which a data transmission request specifying a processable format is automatically transmitted to the data transmission terminal.

Upon receiving the transmission request specifying the format, the transmitting terminal receives (AC) as a reception response.
K) to the receiving terminal, and further, data (ex. AV data) encoded in the requested format
To the receiving terminal.

In such a sequence, for example, AV
The encoded data of the data can be transmitted in a format that can be decoded by the receiving terminal. For example, in a receiving terminal, for data received from a first data transmitting terminal,
Even if an MPEG decoding process using the MPEG codec is being executed, a data format capable of software decoding is provided if a processing program capable of software decoding is provided and resources such as a CPU can be decoded. Is transmitted to the second transmitting terminal as a transmission request request, for example, MPEG1
Receiving the encoded data in a format that allows software decoding, such as
Decoding using the EG codec and decoding using the CPU can be processed in parallel.

FIG. 10 shows the structure of a protocol stack applicable to each coded data of FIG. 7 and control data transmission / reception of data communication such as list request and list transmission.
The stack in FIG. 10 corresponds to the OSI hierarchical model, and includes, for example, Ethernet (XEROX trademark) as a physical layer, a data link layer, and I as a network layer from the lowest layer.
P, as transport layer, upper layers are MPEG1, M
UDP for coded data communication such as PEG2,
An example of a configuration to which TCP is applied when the upper layer is corn troll information communication such as a transmission request and a list transmission / reception is shown.

Next, FIG. 11 shows a processing sequence when a format change request is sent from a receiving terminal that is receiving encoded data to a transmitting terminal that is transmitting encoded data.
This will be described with reference to FIG.

First, a format change request is transmitted from the receiving terminal that is receiving data to the transmitting terminal. Further, the receiving terminal transmits to the transmitting terminal a coding format executable by the transmitting terminal. , And a resource list indicating a format that can be actually executed is requested from the transmission side based on the status of resources such as a codec and a CPU of the transmission side terminal. The data transmitting side transmits the transmission format list and the resource list to the receiving terminal in response to the list request. These lists are the same as the lists shown in FIGS.

The receiving terminal that has received the transmission format list and the transmission resource list provides the receiving user with information (transmitting terminal user name) related to the transmitting terminal and desired information through the display I / F 105 in FIG. A message prompting selection of a reception format and a resource is displayed on the display 32. Input / output I / F in FIG.
When the user's selection result is input by 103, the receiving terminal transmits the selection result to the transmitting terminal as a reception format and a resource request.

The user selects, based on the list, a format that can be transmitted at the transmitting terminal and a decodable format to be changed at the own terminal, and transmits a transmission request to which data indicating the selected format is added to the transmitting terminal. Send to terminal. This transmission request may be executed by adding a selection identifier to the received transmission format list and transmission resource list and returning the transmission format list and the transmission resource list to the transmitting terminal.

Upon receiving the transmission request specifying the format, the transmitting terminal receives (AC) as a reception response.
K) to the receiving terminal, and further converts the data to the requested format and encodes it (ex. AV
Data) to the receiving terminal.

Next, a processing sequence when format specification and data reception are performed using a reception request from the receiving terminal to the transmitting terminal as a processing start condition will be described with reference to FIG.

First, a data receiving request is transmitted from a receiving terminal receiving data to a transmitting terminal. Further, the receiving terminal actually executes the transmitting terminal based on the transmission format list that lists the encoding formats that can be executed by the transmitting terminal and the status of resources such as the codec and CPU of the transmitting terminal. Requests a resource list from the sender indicating the possible formats. The data transmitting side transmits the transmission format list and the resource list to the receiving terminal in response to the list request. These lists are the same as the lists shown in FIGS.

The receiving terminal that has received the transmission format list and the transmission resource list provides the receiving user with information relating to the transmitting terminal (user name of the transmitting terminal) and desired information through the display I / F 105 in FIG. A message prompting selection of a reception format and a resource is displayed on the display 32. Input / output I / F in FIG.
When the user's selection result is input by 103, the receiving terminal transmits the selection result to the transmitting terminal as a reception format and a resource request.

The user selects, based on the list, a format that can be transmitted by the transmitting terminal and a decodable format to be changed in the own terminal, and transmits a transmission request to which data indicating the selected format is added to the transmitting terminal. Send to terminal. This transmission request may be executed by adding a selection identifier to the received transmission format list and transmission resource list and returning the transmission format list and the transmission resource list to the transmitting terminal.

Upon receiving the transmission request specifying the format, the transmitting terminal receives (AC) as a reception response.
K) to the receiving terminal, and further converts the data to the requested format and encodes it (ex. AV
Data) to the receiving terminal.

FIG. 13 is a conceptual diagram of a connection configuration for executing data transmission and reception. The data transmission / reception units 30, 40, and 50 are connected by a network such as the Internet.
2, data input / output devices such as video cameras 33, 43, 53, microphones 34, 44, 54, speakers 35, 45, 55, and keyboards 36, 4.
6, 56, and control information input devices such as mice 37, 47, and 57 are connected.

Each of the personal computers 31, 41, 51 of the data transmitting / receiving units 30, 40, 50 is as shown in FIG.
As described above, it has a code data processing unit using hardware such as the MPEG2 codec, an encoding or decoding processing program using software, and a control unit such as a CPU that executes processing.

One of the data transmission / reception units 30, 40, and 50 is a transmission terminal of the encoded data, and any of them is a reception terminal of the encoded data. For example, the data transmitting / receiving unit 30 is configured to transmit the MPEG2 encoded data to the data transmitting / receiving unit 30 while the data transmitting / receiving unit 5 transmits the data.
If there is a data transmission request from 0 to the data transmission / reception unit 30, transmission of the format list and the resource list from the data transmission / reception unit 50 to the data transmission / reception unit 30 according to the sequence of FIG. Is performed, and the format selection is performed in the data transmission / reception unit 30. In this case, the data transmitting / receiving unit 30
Since the G2 codec is being used, processing of MPEG2 decoded data cannot be executed, and a format that can be software-decoded, such as MPEG1, is selected and a transmission request is issued to the data transmitting / receiving unit 50.
In response to the transmission request, the data transmitting / receiving unit 50
Data transmission to the data transmission / reception unit 30 is performed in the format of No. 1. The data transmission / reception unit 30 can execute the decoding of MPEG1 by using the CPU in parallel with the MPEG2 decoding processing by the currently executed MPEG2 codec.

As described above, by executing the process of designating the format before the data transmission / reception of the encoded data to be transferred via the network, the parallel processing of two or more encoded data can be executed at the receiving terminal. Highly efficient data transmission / reception and encoded data processing can be performed.

The present invention has been described in detail with reference to the specific embodiments. However, it is obvious that those skilled in the art can modify or substitute the embodiment without departing from the spirit of the present invention. That is, the present invention has been disclosed by way of example, and should not be construed as limiting. In order to determine the gist of the present invention, the claims described at the beginning should be considered.

[0078]

As described above, according to the data receiving apparatus, the data transmitting apparatus, the data communication system, the data receiving method, and the data transmitting method of the present invention, the format information that can be encoded on the data transmitting side is provided. Transmitted from the data transmitting device to the data receiving device, in the data receiving device, the received format information and a data transmission request that specifies a format based on a decoding format executable in the receiving device, to the data transmitting device,
Since the coded data according to the specified format is transmitted to the receiving device based on the data transmission request, the decoding process is being executed in one of the hardware and software resources of the receiving device. Even if there is, it is possible to execute a data transmission request by specifying a format for executing decoding using the other resource, and efficient data reception and decoding by executing both hardware and software functions in parallel. It becomes possible.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a network system configuration according to the present invention.

FIG. 2 is a diagram illustrating a configuration of an RTP header in an IP packet transferred in the system of the present invention.

FIG. 3 is a diagram illustrating a UDP header configuration in an IP packet transferred in the system of the present invention.

FIG. 4 is a diagram illustrating an IP header configuration in an IP packet transferred in the system of the present invention.

FIG. 5 is a block diagram showing a configuration of a data transmitting / receiving device of the present invention.

FIG. 6 is a block diagram showing an MPEG codec configuration of the data transmitting / receiving device of the present invention.

FIG. 7 is a diagram illustrating a processing sequence (example 1) executed between a data transmitting side terminal and a receiving side terminal in the system of the present invention.

FIG. 8 is a diagram showing a configuration example of a format list used in the system of the present invention.

FIG. 9 is a diagram showing a configuration example of a resource list used in the system of the present invention.

FIG. 10 is a diagram illustrating a protocol stack for data transmission and reception in the system of the present invention.

FIG. 11 is a diagram illustrating a processing sequence (example 2) executed between a data transmitting side terminal and a receiving side terminal in the system of the present invention.

FIG. 12 is a diagram illustrating a processing sequence (Example 3) executed between a data transmitting side terminal and a receiving side terminal in the system of the present invention.

FIG. 13 is a diagram illustrating a configuration of a data transmission side device and a reception side device, and an example of a network connection configuration in the system of the present invention.

[Explanation of symbols]

 11 Receiving terminal 21, 22, 23 Transmitting terminal 30, 40, 50 Data transmitting / receiving unit 31, 41, 51 Data transmitting / receiving device (PC) 32, 42, 52 Display 33, 43, 53 Video camera 34, 44, 54 Microphone 35, 45, 55 Speakers 36, 46, 56 Keyboard 37, 47, 57 Mouse 101 MPEG codec 102 Network interface 103 Input / output interface 104 AV interface 105 Display interface 106 CPU 107 Memory 108 HDD 109 PCI bus 201 MPEG video encoder 202 MPEG audio Encoder 203 MPEG multiplexer 204 RTP packet generator 205 UDP packet generator 206 IP packet generator 207 P I interface 208 IP packet expansion means 209 UDP packet expansion unit 210 RTP packet expansion means 211 MPEG Demultiplexer 212 MPEG video decoder 213 MPEG audio decoder

Claims (16)

[Claims] 1. A data receiving apparatus receives encoding format information that can be transmitted by a data transmitting apparatus, and selects format information selected from the encoding format information based on a decoding processing function executable in the data receiving apparatus. A process of transmitting a request as an encoded data transmission request to the data transmission device. 2. The data receiving apparatus according to claim 1, further comprising a decoding unit for decoding the encoded data by hardware, and a control unit for executing a decoding process of the encoded data by software, and capable of executing both decoding processes in parallel. It has a configuration, determines whether or not decoding processing is performed by each function of hardware and software, and executes processing of transmitting an encoded data transmission request specifying a processable format to the data transmitting apparatus. The data receiving device according to claim 1, having a configuration. 3. An encoding format information that can be transmitted by the data transmitting apparatus includes: a format list listing encoding processing formats possessed as functions of the data transmitting apparatus; and a format list of encoding processing resources of the data transmitting apparatus. The data receiving device according to claim 1, further comprising: a resource list in which usage status information is listed. 4. The data receiving device, comprising: display means for displaying coding format information received from the data transmitting device; and format selection information designated as a receiving format from the coding format information displayed on the display means. The data receiving apparatus according to claim 1, further comprising: input means for inputting the following. 5. A data transmitting apparatus, comprising: transmitting, to a data receiving apparatus, encoding format information that can be transmitted by the data transmitting apparatus, and based on a format-designated encoded data transmission request received from the data receiving apparatus. A data transmission device configured to execute a process of transmitting encoded data based on a specified format. 6. The data transmitting apparatus, as the encoding format information, a format list listing encoding processing formats possessed as functions of the data transmitting apparatus, and use of encoding processing resources of the data transmitting apparatus. The data transmission apparatus according to claim 5, comprising: a resource list in which status information is listed. 7. The data transmitting apparatus has a data encoding unit by hardware and a control unit to execute data encoding by software, and performs an encoding process by hardware and software functions. 6. The apparatus according to claim 5, wherein the execution status of the data transmission device is detected to generate a resource list listing usage status information of encoding processing resources of the data transmission device.
A data transmission device according to claim 1. 8. A communication system for transmitting and receiving encoded data, comprising: a data transmitting device having an encoding processing function in a plurality of formats; and a data receiving device having a decoding processing function in a plurality of formats. The device transmits the transmittable encoding format information of the data transmitting device to the data receiving device and, based on the format-specified encoded data transmission request received from the data receiving device, generates a code based on the specified format. The data receiving device receives the transmittable encoding format information of the data transmitting device, based on a decoding process function executable in the data receiving device, Transmitting the selected format information selected from the encoding format information to the data Communication system characterized by having a configuration for executing processing of transmitting the encoded data transmission request to the location. 9. A data receiving method, comprising: a step of receiving encoding format information that can be transmitted by a data transmitting device; and a selection process selected from the encoding format information based on a decoding processing function executable by the data receiving device. Transmitting a format information as an encoded data transmission request to the data transmitting apparatus. 10. The data receiving method further comprises: a step of determining whether or not decoding processing is performed by hardware and software functions of the data receiving apparatus; and transmitting a coded data transmission request specifying a processable format. The data receiving method according to claim 9, comprising: transmitting to the data transmitting device. 11. The data receiving method further comprises: a display step of displaying encoding format information received from the data transmitting apparatus; and selecting a format designated as a receiving format from the encoding format information displayed in the displaying step. The data receiving method according to claim 9, further comprising: an input step of inputting information. 12. A data transmission method, comprising: transmitting, to a data receiving device, encoding format information that can be transmitted by a data transmitting device; and transmitting a format-specified encoded data transmission request received from the data receiving device. Transmitting encoded data based on the designated format based on the data format. 13. The data transmission method according to claim 1, further comprising detecting an execution state of an encoding process by each function of a hardware data encoding unit and a software executing a data encoding process. 13. The data transmission method according to claim 12, comprising: a step of generating a resource list listing usage information of encoding processing resources of the data transmission apparatus. 14. A data communication method for transmitting and receiving coded data, the method comprising: transmitting, in a data transmitting apparatus, encoding format information transmittable by the data transmitting apparatus to the data receiving apparatus; Receiving the encoding format information, and transmitting to the data transmission device an encoded data transmission request designating a selection format selected based on a decoding processing function executable in the data reception device; A data communication method, comprising: transmitting coded data based on a specified format based on a format specification coded data transmission request received from the data receiving device. 15. A program storage medium for providing a computer program for executing a data receiving process on a computer system, the computer program comprising a step of receiving encoding format information that can be transmitted by a data transmitting device. And transmitting the selected format information selected from the encoded format information as an encoded data transmission request to the data transmitting device, based on a decoding processing function executable in the data receiving device. Program storage medium. 16. A program storage medium for providing a computer program for causing a data transmission process to be executed on a computer system, the computer program comprising: a data transmission device that transmits an encoding format information that can be transmitted by a data transmission device; Transmitting a coded data based on a specified format based on a format specification coded data transmission request received from the data receiving apparatus. Medium.