JP2806413B2 - How to manage multi-channel compressed data - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for managing compressed data in which images and sounds are compression-coded, and more particularly to a method for compressing and coding a plurality of continuous images (moving images) and sounds (so-called multi-channel information). The present invention relates to an efficient management method of compressed multi-channel compressed data.

[0002]

2. Description of the Related Art Recently, moving picture compression techniques have begun to be used not only for transmission means such as broadcasting and communication, but also for storage media (recording media and recording means) such as CDs and ROMs. Such a recording medium is required to support not only ordinary television images (video images) but also a plurality of images (moving images), multi-images having sound, and bilingual sound. However, in the compression of moving images, compression is performed based on the preceding and following images (frames, fields).
Inter-picture (picture) prediction encoding is performed. For this reason, a moving image is simply considered as a collection of still images having a fixed capacity, and data cannot be managed and multi-reproduction cannot be performed as in the related art. That is, since the amount of data of the compressed moving image data differs for each image, the change in the data amount of the recording medium (access point) is not simply proportional to the time code of the image.

Conventionally, when a plurality of images and sounds (digitized multi-channel information) are recorded in a distributed manner for each frame, the management information is placed at the beginning (header portion) of an actual frame, and Interpreting this in time,
The desired channel was selected. With such a configuration, a plurality of channels such as image A-CH, image B-CH, image C-CH, image D-CH, audio a-CH, audio b-CH, audio c-CH, audio A d-CH or the like is recorded, and at the time of reproduction, a necessary channel, for example, an image A-CH or an audio c-CH is selected and reproduced.

[0004]

However, as described above, when images and sounds are compressed and recorded, generally, the ratio between the data transfer amount and the information amount is not constant (the image and sound information amounts are not constant). Changes). Further, in the identification by the header portion, the channel information can be determined only by reading the content portion of the information. Therefore, audio and image management information is also recorded in the header portion, but hardware and software for selecting and reproducing (restoring) the information are required, and the information (amount) is also redundant. . Therefore, the present invention efficiently manages multi-compressed data in which a plurality of images and a plurality of sounds (multi-channels) are compression-encoded, so that channel selection can be performed without a burden on hardware or software. It provides a possible management method.

[0005]

In order to solve the above-mentioned problems, for example, as shown in FIG. 1, a plurality of continuous images (moving images), multi-channel compressed data (for example, , Two channels of image A-CH and image B-CH and two channels of audio a-CH and audio b-CH), wherein the multi-channel compressed data is distributed at predetermined time intervals in block units ( A multi-channel compressed data management method characterized in that the channel length is controlled by a block length 12) and channel management information 16t indicating a block interval (interval g indicated by a gap interval 21) of each channel is provided. Is provided.

Further, the channel management information 16t is composed of the block interval of each channel and its repetition information (the interval g indicated by the gap interval 21 and the number of repetitions r in the supplementary information 20). The present invention provides a method of managing multi-channel compressed data as described above, characterized in that the channel management information is provided every time.

[0007]

According to the method for managing multi-channel compressed data as described above, an image is not managed in units of images (frames or fields) having a variable capacity as in the prior art, but in units of blocks having a fixed capacity. Be managed. Further, skip reading is performed based on the block interval (gap interval 21) specified by the channel management information 16t, and the data of the distributed specific channel is continuously reproduced. In addition, while the block intervals (gap intervals 21) are equal, skip reading at the same block intervals is repeatedly executed without requiring new channel management information (without reading).

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a method for managing compressed multi-channel compressed data according to the present invention will be described below in detail with reference to the drawings. FIG. 1 is an example of a management format when the present invention is applied to a disk medium. As shown in FIG. 1A, a disc medium (for example, an optical disc such as a CD / ROM) 11 is recorded and reproduced in a unit of information called a normal block (12). Access at the time of recording and reproduction is performed in units of this block. The disk medium 11 is divided into a management information area 13 and a data information area 14, and the data information area 14 records multi-channel compressed data.

Further, as shown in FIG. 1C, the multi-channel compressed data includes image data (for example, image AC
H, two channels of image B-CH, indicated by A and B in the figure)
It is composed of audio data (for example, two channels of audio a-CH and audio b-CH, indicated by a and b in the figure), and is divided every unit time (reproduction time before compression, for example, 1 / frame which is one frame time).
(Every 30 seconds) are dispersed (interleaved) and a predetermined repetition pattern (image A-CH, image B-CH, audio a-CH,
Audio b-CH repetition order). The moving image data, which is multi-channel compressed data, is data that has been subjected to inter-picture (frame or field) predictive encoding and has been compressed, so that the capacity per frame is not a fixed amount. One image data and audio data corresponding to the image data are usually formed over a plurality of different blocks.

As shown in FIG. 1B, the management information area 13 is divided into information units called records (management records 16). This management record 1
6 stores a name 17 of the management information, a block number 18 indicating the address of the corresponding information, an information size 19, a gap interval 21, and additional information 20 attached to the management information. The block number 18 indicates a block position (address) that is the start position of the data, and the information size 19 indicates the information capacity of the data by, for example, the number of bytes or the number of blocks. The management record 16 includes a record for managing the entire multi-channel compressed data and a record for continuously managing a specific channel. The multi-channel compressed data in the data information area 14 is accessed and reproduced on a block-by-block basis by the management records 16 in the management information area 13.

Next, a management record for continuously reproducing a specific channel (hereinafter, referred to as a channel management record 16t in particular) will be described. The channel management record 16t is efficiently configured such that it can be managed with a small number of management records based on the gap interval 21 and the number of repetitions r in the incidental information 20. The gap interval 21 is used to continuously manage a specific channel, for example, to continuously reproduce only the audio b-CH.
Meanwhile, the next audio b-CH, which is a repetition part of another channel
(That is, in FIG. 1C, the image A-
The interval g) between the CH, the image B-CH, and the audio a-CH is indicated by the number of blocks. When reproduction is performed skipping the number of blocks (interval g) indicated by the gap interval 21, a specific channel (data amount d) is continuously reproduced.

As described above, the image A-CH and the image B-CH
The four channels of CH, audio a-CH, and audio b-CH are dispersed in unit time and recorded in a predetermined repetition pattern. However, since these multi-channel compressed data are compressed data, the data amount of each channel, that is, the number of blocks is not constant. However, in the case of continuous data such as a moving image, the data amount of each channel (the number of blocks) often does not fluctuate significantly during a certain period, and the same value continues in a section where the gap interval 21 is constant.

Therefore, the supplementary information 20 records the number of repetitions r when the gap intervals are equal.
That is, as shown in FIG. 1C, when the interval g = 5 is continuous twice for the audio b-CH, the gap interval 21 is set to “5” as the channel management record 16t in FIG. ”, The number of repetitions r in the supplementary information 20 is“ 2 ”.
And Since the channel management records 16t are configured in this manner, the number of channel management records is drastically reduced, the management information area 13 is not increased, and the capacity of the recording medium can be used efficiently.

At the end position (block) of a specific channel, "end information" is written in the supplementary information 20. Until there is "end information", continuous channel management records for the specific channel are read one after another, and based on this, compressed data of the specific channel is continuously reproduced.

Next, a recording / reproducing system will be described. FIG. 2 is a configuration diagram of the recording / reproducing system. VTR1
The video and audio data from are compressed by the computer 2 and the management record as described above is generated and recorded on the disk medium 11 in the format shown in FIG. 3 is a disk medium 11
Is a disk device for recording / reproducing, and 4 is an operation unit of the computer 2, and 5 is a display device. Then, at the time of recording and editing, the above-described channel management record 16t is generated and written in the management information area 13 so that a specific channel can be continuously reproduced.

FIG. 3 is a flowchart showing a procedure for creating and recording a channel management record. First, the name of the management information 17, the block number 18 indicating the address of the corresponding information, the information size 19, the gap interval 21, A channel management record 16t having the additional information 20 is created (step 10).
1). Next, it is checked whether the gap (interval g) up to the next data position of the channel has changed (step 10).
2). If the gap (interval g) is the same, additional information 2
Increment the number of repetitions of 0 (step 10)
3). When the gap (interval g) changes, the previous channel management record 16t is recorded (step 1).
04), the next channel management record is created (step 101). This is repeated until the specific channel ends (step 105), and "end information" is written in the supplementary information 20 of the last channel management record (step 106). In this way, the gap interval 2
1, a channel management record group having ancillary information 20 (that is, channel management information 1 that is provided each time the channel block interval changes and is recorded continuously)
6t) is created and recorded in the management information area 13.

At the time of reproduction, image data and audio data of a specific channel are sequentially read from the data information area 14 corresponding to the designated number of blocks by referring to the management record group in the management information area 13 of the disk medium 11. It is read and played back continuously. FIG. 4 is a flowchart showing a procedure of continuous reproduction of a specific channel using a channel management record.

Except for continuous reproduction of a specific channel, normal processing is performed (steps 201 and 202). At the time of continuous reproduction of a specific channel, the corresponding channel management record 16t is read from the management information area 13 (step 203), and the corresponding data is read from the data information area 14, decompressed and reproduced (step 203). Step 204). The blog is skipped by the gap length of the channel management record 16t (step 2).
05), this is repeated for the number of repetitions of the additional information 20 (step 206). When the repetition is completed (that is, when the gap length is different), the next successive channel management record 16t is read (step 20).
3) This process is continued until the specific channel ends (step 207).

As described above, the channel management record 16
The gap length is indicated by t, so that the blog can be skipped and read, and it is not necessary to have voice and image management information in the header part as in the conventional case, and it is not necessary to decompress and decode each header. Absent. Therefore,
It is possible to select only a specific channel and continuously reproduce the data without imposing a large burden on hardware and software.

When the gap interval g is equal, the channel management record 16t is configured to record the number of repetitions r in the supplementary information 20, so that the number of channel management records does not increase, and The capacity of the medium can be used efficiently.

By the way, the gap interval 21 and the supplementary information 20 are not recorded and edited as described in the embodiment, but are reproduced as necessary in the same manner as in the recording and editing process described above.
May be created and recorded in the management information area 13 for use.

As information source 1, C is used instead of VTR.
A DROM player may be used and a hard disk or a memory may be used instead of the disk recording / reproducing device 3 to be used for file management of a normal personal computer system having a CDROM player.

[0023]

As described above in detail, according to the method of managing compressed multi-channel compressed data according to the present invention, since the management is performed by the channel management record, a large burden is imposed on hardware and software. , And only the specific channel can be selected and continuously reproduced. When the block interval (gap interval) is equal, the number of repetitions is recorded as the channel management record, so that the number of channel management records does not increase and the capacity of the recording medium can be efficiently reduced. Available.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining an embodiment of a method for managing multi-channel compressed data according to the present invention, and is an example of a management format when it is applied to a disk medium.

FIG. 2 is a configuration diagram of a recording / reproducing system that executes a method for managing multi-channel compressed data.

FIG. 3 is a flowchart illustrating a procedure for creating and recording a channel management record.

FIG. 4 is a flowchart showing a procedure of continuous reproduction of a specific channel using a channel management record.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 VTR (information source) 2 Computer 3 Disk recording / reproducing apparatus 11 Disk medium 12 Signal block 13 Management information area 14 Data information area 16 Management record 16t Channel management record 20 Additional information 21 Gap interval 102, 103 Gap interval at the time of recording Step 205 to check repetition of step 205, 206 Step of using repetition of gap interval during reproduction d Data amount g Gap interval

Claims (2)

(57) [Claims] 1. A method for managing multi-channel compressed data in which a plurality of continuous images and sounds are compression-encoded, wherein the multi-channel compressed data is distributed at predetermined time intervals and managed in block units. A method of managing multi-channel compressed data, wherein channel management information indicating a block interval of each channel is provided and managed. 2. The apparatus according to claim 1, wherein the channel management information comprises a block interval of each channel and its repetition information, and the channel management information is provided every time the block interval of the channel changes. 2. The method for managing multi-channel compressed data according to 1.