JP2009171277A - Information data stream recording apparatus and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recoding apparatus and a method, which perform recoding adapted to the remaining capacity of a recoding medium. <P>SOLUTION: The apparatus includes: a means (102) for detecting a size Bs of an input information stream; a means (106) for detecting a size Bp of an extracted stream having video and audio packets extracted; and a means (113) for detecting a remaining capacity C of a medium. If the remaining capacity C is greater than the size Bs, then the information stream is recorded in the recoding medium as is, and if the remaining capacity C is smaller than the size Bs and greater than the size Bp, then the extracted stream is recorded in the recording medium. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method and apparatus for recording a data stream such as a digital television broadcast on a medium.

  In digital television broadcasting, it is possible to broadcast a large amount of high-quality video data with a limited transmission capacity by transmitting a compressed data stream obtained by compressing and encoding a video signal by an MPEG encoding method ( Non-patent document 1). The compressed and encoded video and audio data are packetized and each packet is multiplexed and broadcast, but the data broadcast packet is multiplexed and transmitted together with the video and audio packets. Data broadcasting includes, for example, news information, weather forecast information, and data information associated with a program. In the case of a soccer program, real-time information such as player introduction information or play information such as the ball dominance rate is transmitted.

  In order to record such a digital television broadcast stream on a recording medium, there are stream recording for recording the broadcast stream as it is and encoding recording for compressing and recording the broadcast stream. Stream recording can be recorded with the same high image quality and high sound quality as broadcast quality, and data broadcasting can also be recorded as it is. On the other hand, in encoding recording, a broadcast stream is once decoded, and the decoded data is recompressed by MPEG encoding or the like. By compressing the bit rate to about 8 Mbps, the recording capacity can be reduced to 1/3 for BS broadcasting and 1/2 for terrestrial digital broadcasting. That is, encoding recording can be performed for a long time.

In Patent Document 1 or Patent Document 2, it is selected whether the stream recording is performed according to the data size of the broadcast stream and the remaining capacity of the recording medium, or the compression recording is performed for encoding recording, and the bit rate for further encoding recording A method for determining the value by the remaining capacity is disclosed.
JP-A-10-199142 JP 2002-10200 A ISO / IEC 13818-2 (MPEG2 video)

  However, in the case of stream recording, since the bit rate of data is as high as about 24 Mbps for BS broadcasting and about 17 Mbps for terrestrial digital broadcasting, a large recording capacity is required. On the other hand, encoding noise is generated by recompression by encoding recording, and there is a problem that image quality and sound quality deteriorate.

  In a first aspect of the invention, an apparatus for recording an information stream on a medium is provided. The apparatus outputs a remaining capacity detecting means for detecting the remaining capacity C of the medium, an attribute detecting means for detecting an attribute of each packet of the information stream, and an extracted stream obtained by extracting a specific packet detected by the attribute detecting means. Filtering means, a first data size detecting means for detecting the data size Bs of the information stream, a second data size detecting means for detecting the data size Bp of the stream extracted by the filtering means, and a remaining capacity C When the data size is larger than the data size Bs, an information stream is recorded, and when the remaining capacity C is smaller than the data size Bs and larger than the data size Bp, a recording unit for recording the stream extracted by the filtering unit is provided. It is to be prepared.

    In a second aspect of the invention, a method for recording an information stream on a medium is provided. The method outputs a remaining capacity detecting step for detecting a remaining capacity C of the medium, an attribute detecting step for detecting an attribute of each packet of the information stream, and an extracted stream obtained by extracting a specific packet detected in the attribute detecting step. Filtering step, a first data size detecting step for detecting the data size Bs of the information stream, a second data size detecting step for detecting the data size Bp of the stream extracted in the filtering step, and a remaining capacity C When the data size is larger than the data size Bs, an information stream is recorded. When the remaining capacity C is smaller than the data size Bs and larger than the data size Bp, a recording step for recording the stream extracted in the filtering step is performed. Have.

  According to the present invention, if the remaining capacity is sufficient, the broadcast stream is recorded as it is, and if not, the extracted stream composed of the video and audio packets from which the data packet of the data broadcast is deleted is recorded, It is possible to record with a small remaining capacity without deteriorating the sound quality.

(Embodiment)
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a block diagram showing a configuration of a recording apparatus according to an embodiment of the present invention. Here, an example will be described in which a digital television broadcast is once recorded on the hard disk 107 and the recording data of the hard disk 107 is recorded on the disk 112.

  First, recording processing of the digital television broadcast stream on the hard disk 107 will be described. The broadcast stream received by the digital television tuner 101 is recorded on the hard disk 107 by the stream recording means 103a. At this time, the first data size detection means 102 detects the data size Bs of the broadcast stream to be recorded. The packet analysis means 105a analyzes the attribute of each packet in the broadcast stream. The filter means 104a outputs an AV stream obtained by extracting video and audio packets from each packet of the broadcast stream. The second data size detection means 106 detects the data size Bp of the AV stream. The detection result of the first data size detection unit 102 and the detection result of the second data size detection unit 106 are input to the control unit 110.

  Next, processing for recording the broadcast stream recorded on the hard disk 107 on the disk 112 will be described. First, the remaining capacity detection unit 113 detects the remaining capacity C of the disk 112. The detection result is input to the control unit 110. The broadcast stream recording means 103b is for recording the broadcast stream read from the hard disk 107 as it is on the disk 112, like the broadcast stream recording means 103a. The packet analysis means 105b analyzes the attributes of each packet in the broadcast stream as in the packet analysis means 105a, and the filter means 104b outputs an AV stream in which video and audio packets are extracted from each packet in the broadcast stream as in the filter means 104a. To do. The extracted stream recording means 108 is for recording the extracted AV stream on a disc. The encoded stream recording unit 109 decodes the extracted AV stream, and performs compression encoding processing so as to obtain a predetermined data size Be and records the decoded AV stream. The compression coding rate may be determined so that the data size Be is smaller than the remaining capacity C. The selector 111 is controlled by the control unit 110 and selects one of the three recording units of the broadcast stream recording unit 103b, the extracted stream recording unit 108, and the encoded stream recording unit 109.

  Hereinafter, the selection process of the three recording units will be described. First, when the remaining capacity C is larger than the data size Bs of the broadcast stream, the broadcast stream is recorded on the disk 112 as it is by the broadcast stream recording means 103b. When the remaining capacity C is smaller than the data size Bs of the broadcast stream and larger than the data size Bp of the AV stream, the extracted stream recording means 108 records the AV stream on the disc 112. Finally, when the remaining capacity C is smaller than the data size Bp of the AV stream and larger than the data size Be of the encoded stream, the encoded stream is recorded on the disc 112 by the encoded stream recording means 109. When the remaining capacity C is smaller than the data size Be of the encoded stream, the entire encoded stream cannot be recorded. Therefore, the compression rate may be set so that the data size Be is smaller than the remaining capacity C. The selection information recording unit 114 records information for determining the selected stream type on the disc 112.

  As described above, when the remaining capacity of the recording medium is sufficient, the broadcast stream including the data packet is recorded as it is, and when the remaining capacity is small, the data packet is deleted and only the video and audio AV stream is recorded. As a result, the image quality and sound quality can be recorded while maintaining the broadcast quality. Further, when the remaining capacity is small, it is only necessary to perform compression encoding processing for recording, and it is possible to perform a recording process suitable for the remaining capacity of the recording medium.

  In addition, since the recorded stream type is recorded on the disc, it is possible to determine whether the stream is a broadcast stream, an AV stream, or an encoded stream at the time of reproduction. In the case of a broadcast stream, data broadcast packets are also recorded, so that data broadcast can be reproduced. On the other hand, when the reproduction stream is an AV stream, the data broadcast cannot be reproduced. Therefore, in the case of an AV stream, even if a data broadcast reproduction instruction is received from the user, the data broadcast reproduction process is not performed. At this time, a message that data broadcasting cannot be reproduced may be sent.

  Further, when the recorded stream list is displayed, it may be displayed whether it is a broadcast stream, an AV stream, or an encoded stream. For example, a mark indicating each stream type may be added to the recording stream list. Accordingly, the user can recognize whether the stream is a data broadcast reproducible stream. Further, the stream type may be associated with the recording mode, and the stream type can be recognized by displaying the recording mode.

  The broadcast stream recording means 103a and 103b, the filter means 104a and 104b, and the packet analysis means 105a and 105b are provided in two, but one means may be used for each.

  FIG. 2 is a flowchart showing a recording / reproducing method according to an embodiment of the present invention. Hereinafter, each processing step will be described in detail. Here, an example will be described in which a digital television broadcast stream is recorded on a hard disk and then dubbed and recorded on an optical disk.

  First, in step 201, the data size Bs of the broadcast stream is detected. The number of packets recorded when the broadcast stream is recorded on the hard disk may be counted, or after recording on the hard disk, the data size Bs may be detected from the disk capacity used for recording. Next, the data size Bp of the AV stream obtained by extracting only video and audio packets from the broadcast stream is detected. When a broadcast stream is recorded on the hard disk, each packet of the stream may be analyzed and video and audio packets may be counted. Step 203 detects the remaining capacity C of the optical disk.

  Next, in step 204, the remaining capacity C is compared with the broadcast stream size Bs. If the remaining capacity C is larger, the process proceeds to step 206, and the broadcast stream is recorded on the optical disc as it is. If the recording capacity C is smaller than the broadcast stream size Bs, the process proceeds to step 205.

  In step 205, the remaining capacity C is compared with the AV stream size Bp. If the remaining capacity C is larger, the process proceeds to step 207 to record the AV stream on the optical disc. If the recording capacity C is smaller than the AV stream size Bp, the process proceeds to step 208 to perform the encoding recording process. In the encoding recording process, compression encoding is performed so as to be smaller than the remaining capacity C.

  As described above, when the remaining capacity of the recording medium is sufficient, the broadcast stream including the data packet is recorded as it is, and when the remaining capacity is small, the data packet is deleted and only the video and audio AV stream is recorded. As a result, the image quality and sound quality can be recorded while maintaining the broadcast quality. Further, when the remaining capacity is small, recording can be performed by compression encoding processing, and recording processing suitable for the remaining capacity of the recording medium can be performed.

  Since the recording apparatus and the recording method according to the present invention can select a recording method according to the capacity of the medium, the recording apparatus and the recording method can be applied to an apparatus for recording digital TV broadcasts and dubbing recording.

1 is a block diagram showing a configuration of a recording apparatus according to an embodiment of the present invention. 7 is a flowchart showing a recording method according to the embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Digital television tuner 102 Broadcast stream data size Bs detection means 103a, 103b Broadcast stream recording means 104a, 104b Filter means 105a, 105b Packet analysis means 106 Extracted stream data size Bp detection means 107 Hard disk 108 Extracted stream recording means 109 Encoding stream Recording means 110 Control means 111 Selection means 112 Optical disc 113 Remaining capacity detection means 114 Selection information recording means

Claims (6)

A recording device for recording an information stream on a medium,
A remaining capacity detecting means for detecting the remaining capacity C of the medium;
Attribute detection means for detecting the attribute of each packet of the information stream;
Filtering means for outputting an extracted stream obtained by extracting the specific packet detected by the attribute detection means;
First data size detection means for detecting the data size Bs of the information stream;
Second data size detection means for detecting the data size Bp of the stream extracted by the filtering means;
When the remaining capacity C is larger than the data size Bs, the information stream is recorded,
An information recording apparatus comprising: a recording unit that records the stream extracted by the filtering unit when the remaining capacity C is smaller than the data size Bs and larger than the data size Bp. The information recording apparatus according to claim 1, wherein the filtering unit extracts at least a packet related to video and audio. An encoding means for compressing and encoding video and / or audio data of the information stream so as to have a predetermined data size Be;
When the remaining capacity C is larger than the data size Bs, the information stream is recorded,
When the remaining capacity C is smaller than the data size Bs and larger than the data size Bp, the stream extracted by the filtering means is recorded,
2. The information recording apparatus according to claim 1, wherein when the remaining capacity C is smaller than the data size Bp and larger than the data size Be, the stream encoded by the encoding means is recorded. . 4. The information recording apparatus according to claim 3, wherein the compression encoding rate is determined so that the data size Be is equal to or less than the remaining capacity C. 2. The information recording apparatus according to claim 1, wherein information indicating that the information stream is recorded on the medium or the stream extracted by the filtering unit is recorded is recorded on the medium. . A method for recording an information stream on a medium, comprising:
A remaining capacity detecting step for detecting a remaining capacity C of the medium;
An attribute detection step for detecting an attribute of each packet of the information stream;
A filtering step of outputting an extracted stream obtained by extracting the specific packet detected in the attribute detection step;
A first data size detecting step for detecting the data size Bs of the information stream;
A second data size detection step of detecting the data size Bp of the stream extracted in the filtering step;
When the remaining capacity C is larger than the data size Bs, the information stream is recorded,
And a recording step of recording the stream extracted in the filtering step when the remaining capacity C is smaller than the data size Bs and larger than the data size Bp.

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