JPH07107434A - Moving picture recording and reproducing device and video disk - Google Patents

Abstract

PURPOSE:To provide a moving picture recording device and the video disk where picture data obtained by the division of a moving picture signal to plural signal components and efficient compressing and encoding of them are multiplexed and recorded in memories having a small capacity and intra-frame encoded picture data is accessed and reproduced in a short time. CONSTITUTION:The frame of an input moving picture signal is divided into N by a divider 2 and is encoded in encoders 3 to 6 by both of intra-field encoding processing and inter-frame encoding processing and is stored in memories 8 to 11. N code strings outputted from memories 8 to 11 are divided into M by the size of the one-sector capacity of the disk by a code string multiplexer 12 to obtain NXM divided code strings, and these code strings are multiplexed in a prescribed order, and the code string obtained by the code string multiplexer 12 is converted into a format adapted to recording by a recording signal processor 13 and is recorded on the disk 15 in the order from a prescribed sector by a recording and reproducing head 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving image recording / reproducing apparatus and a video disc for dividing an input moving image signal into a plurality of image components for high efficiency compression coding, and recording / reproducing.

[0002]

2. Description of the Related Art In recent years, by compressing and coding an image signal using a high-efficiency coding technique, digital transmission of a moving image signal at a low bit rate and long-time digital recording using an storage medium such as an optical disk are performed. Recording and playback has become possible. Various high-efficiency compression encoding methods have been proposed. For example, a DCT encoding method in which an image signal is divided into a plurality of blocks, discrete cosine transform (DCT) is performed for each block, and DCT coefficients are quantized and encoded, A sub-band coding method or a wavelet transform coding method that divides an image signal into multiple frequency bands and codes each frequency band component, and a prediction code that performs motion compensation to remove redundancy in the time axis direction. There is a chemical method.

Predictive coding is divided into an intra-frame coded image for complete coding within a single image frame and an inter-frame coded image for predicting and coding from coded images of other frames. This is a coding technique. The input moving image signal is divided into a group of a plurality of frame units, and this is
This is called OP (Group Of Picture). For example, it is assumed that the first frame of a GOP is intra-frame coded and the following frames are inter-frame coded.

When performing such high-efficiency encoding on a high-resolution image signal (HD image signal) such as high-definition, a plurality of encoding devices are used in parallel for encoding because the image signal has a large amount of information. It is necessary to process the conversion. To use the encoding devices in parallel, a method of dividing the input image signal into a plurality of small screens and encoding each small screen, dividing the input image signal into components of a plurality of frequency bands and A method for encoding has been proposed.

As shown in FIG. 4, a code string output in parallel from a plurality of coding apparatuses has a code string of image data which is intra-frame coded for each GOP as a head, and is followed by an inter-frame code. The code strings of the processed image data are arranged continuously, and as shown in FIG. 5, they are time-axis-multiplexed in units of 1 GOP, output, and recorded on a recording medium.

[0006]

A recording / reproducing apparatus such as an optical disk is characterized by the convenience of special reproduction by random access to predetermined image data.

When image data compressed and encoded by predictive coding is recorded and reproduced by such a recording / reproducing apparatus, it is impossible to directly access and reproduce the inter-frame encoded image data. This is because the inter-frame coded image data needs to be predicted with reference to the coded image data of another frame, and the coded image data of the frame that is the reference image data needs to be reproduced in advance. is there.

Therefore, in order to reproduce the image data, it is necessary to access the intra-frame encoded image data as a unit.

When an HD image signal is compression-encoded by using a plurality of encoders in parallel, a plurality of code strings output from the encoders are time-axis multiplexed in GOP units as shown in FIG. Therefore, a large-capacity memory for storing 1 GOP image data is required at the output stage of the encoding device. Furthermore, in order to reproduce the image data which has been subjected to the intra-frame coding process for one screen, the intra-frame coded image data of all the divided components is required, and the corresponding intra-frame coding is performed from the time-axis multiplexed code string. It is necessary to selectively retrieve image data. Therefore, in order to access and reproduce the predetermined intra-frame encoded image data, it is necessary to repeat the access for the number of divided components, which causes a delay in the reproduction of the image data, the beginning of the image data, etc. There was a problem that random access takes a very long time.

The present invention solves the above-mentioned conventional problems, and a code string of image data which is divided into a plurality of signal components and is highly efficient coded can be multiplexed and recorded in a small capacity memory. It is an object of the present invention to provide a moving image recording / reproducing apparatus and a video disc capable of accessing and reproducing reproduced image data in a short time.

[0011]

In order to achieve the above object, the moving picture recording / reproducing apparatus of the present invention has N or more fields or frames of an input moving picture signal divided into a plurality of groups.
(N> 1, N is an integer) and a coder for dividing the N image components using both intra-field or intra-frame coding processing and inter-field or inter-frame coding processing. N encoders and a code string output from the N encoders are divided into M (M> 1, M is an integer) division codes of a size of at least one sector of a disk having a sector structure. The N number of memories for dividing into columns and the N × M number of division code strings output from the memory are the mth division code sequence of the nth code sequence in the N × M number of division code sequences. Is the (n, m) th (1 ≦ n ≦ N, 1 ≦ m ≦ M,
n, m are integers and are expressed as a divided code string, and (1, 1),
(2,1), ..., (N, 1), (1,2), (2
2), ..., (N, 2), ..., (1, M),
(2, M), ..., (N, M) are provided in sequence, and a code sequence multiplexing means is provided, and the code sequence obtained by the code sequence multiplexing means is sequentially recorded on a disk from a predetermined sector. Has become.

The video disc for recording / reproducing a moving image according to the present invention has a recording format recorded on the recording track by the moving image recording / reproducing apparatus.

[0013]

In the moving image recording / reproducing apparatus of the present invention, a code string of image data which is divided into a plurality of signal components and which is intra-frame coded or inter-frame coded is multiplexed by a small capacity memory and recorded on a disk. By doing so, it is possible to record the intra-frame coded image data in sector units from the beginning of a predetermined sector, and the thus recorded video disc for a moving image recording / reproducing apparatus of the present invention is a moving image of the present invention. The intra-frame coded image data is accessed and reproduced by the image recording / reproducing apparatus in a short time.

[0014]

Embodiments of the moving image recording / reproducing apparatus and the video disc of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram of a moving image recording / reproducing apparatus according to an embodiment of the present invention.

In FIG. 1, 1 is an A / D converter, 2 is a divider for dividing a digitized image signal into four divided image components, and 3, 4, 5, 6 are four divided image components. This is an encoder that performs high-efficiency compression encoding for each divided image component. In the recording processing unit 7, reference numerals 8, 9, 10, and 11 denote memories for storing code strings output from the four encoders, 12
Is a code string multiplexer that multiplexes the code strings stored in the memory,
13 is a recording signal processor for converting the multiplexed code string into a format suitable for a recording medium, 14 is a recording / reproducing head,
Reference numeral 15 is an optical disk having a sector structure.

In the reproduction processing section 16, 17 is a reproduction signal processor for reading the record data recorded on the optical disk 15 with the recording / reproducing head 14 and outputting a code string, and 18 is a code string output from the reproduction signal processor 17. Are divided into four code strings, and 19, 20, 21, and 22 are memories for storing the code strings divided by the code string divider.

The operation of the present embodiment configured as described above will be described below. First, the input analog moving image signal is converted by the A / D converter 1 into a digital image signal having a predetermined number of bits. To be done. Since the digitized image signal has a large amount of information and cannot be processed by a single encoder, the divider 2 divides it into four components. The division method is to divide the image signal screen into four (vertical division, horizontal division,
There is a screen division method such as cross division, a frequency division method that divides the image signal into four frequency components (high frequency component, middle high frequency component, middle low frequency component, low frequency component), etc. Either method may be used. The code strings encoded and output by the four encoders are respectively (a) and (a) in FIG.
The configurations shown in (b), (c), and (d) are obtained.

FIG. 4 which is output from the four encoders 3-6.
To record the code string shown in to the disk in sector units
Has a size equivalent to the capacity of one sector of the disk.
Each of the four code strings in the memory 8, 9, 10, 11
Which is a code string for the memory capacity from the beginning of₀-a1, I₀-
b1, I₀-c1, I₀-Store d1. Next, the code string multiplexer
A code string I stored in four memories at 12₀-a1, I₀-
b1, I₀-c1, I₀-Multiply d1 in the order of a, b, c, d
To make one code string. 4 in the empty memory
A code string I corresponding to the memory capacity following one code string₀-a
2, I₀-b2, I ₀-c2, I₀-Store each d2, mark
In the sequence multiplexer 12, as in the previous case, the code sequence I ₀-a2, I₀-
b2, I₀-c2, I₀-Multiply in the order of d2. This operation
By repeating, the code string of 1 GOP is divided into multiple
1 is divided into code strings, rearranged in a predetermined order and multiplexed.
It becomes one code string.

FIG. 3 shows the code string thus obtained. Here, since the code string of 1 GOP is a variable length code, the size of the code string differs for each group, but it is desirable that the size of the code string is a fixed length for recording on the disc. For example, if the size of one code string is 6 sectors long as shown in FIG. 2, the dummy data D is added to the end of the code string of each GOP, and the size becomes the sector capacity of the disk. It is a multiple of equal 24 (6 × 4) division code strings. Then, the multiplex code sequence is converted into a format suitable for the recording medium by the recording signal processor 13, and is sequentially arranged by the recording / reproducing head 14 from a predetermined sector of the optical disc 15.

When accessing the predetermined data on the disk arranged in this way, the code string of the image data subjected to the intra-frame coding process may be used as the access point. That is, the sector in which the head of the GOP is recorded becomes the access point. Since the code string of the intra-frame coded image data is continuously arranged from the head of a predetermined sector, the necessary code string can be reproduced by one access operation.

Special reproduction such as fast-forward reproduction can be realized by selectively reproducing only the image data that has been subjected to the intraframe coding process. In this case, the sector in which the code string of the image data at the head of the GOP is recorded is accessed. Then, after the intra-frame encoded image data is reproduced, the operation of accessing the sector in which the code string of the first image data of the succeeding GOP is recorded may be repeated.

Although the image component is divided into four in this embodiment, it may be divided into any N (N> 1, N is an integer). Also, the code string obtained by coding the four divided image components was divided by the sector size of the optical disk into six divided code strings. This is an arbitrary M (depending on the image data and the size of the sector). It goes without saying that M> 1 and M are integers.

The size of the dummy data added to the end of the four code strings may be the size of one or more divided code strings. Further, although the data size of the GOP after adding the dummy data is assumed to be constant in all GOPs, it is not limited to this, and the data size may be different in each GOP.

Further, when arranging the multiple code sequence on the disk, data other than the image data such as audio data may be arranged between the image data of 1 GOP. Further, in the present embodiment, when the high-efficiency compression encoding of the digital image data is performed in frame units, this may be performed in field units. Further, the recording medium of the present embodiment is not limited to the optical disc, and may be a magneto-optical disc, a magnetic disc or the like.

[0025]

As described above, according to the moving picture recording / reproducing apparatus and the video disc of the present invention, a code string divided into a plurality of signal components and subjected to high-efficiency compression coding is formed on the optical disc and has the same sector size. It can be multiplexed and recorded with a small capacity memory. Further, a code string of continuously encoded intraframe encoded image data can be recorded on the optical disc in sector units from the beginning of a predetermined sector, and the intraframe encoded image data can be accessed and reproduced in a short time. It is very effective in practice.

[Brief description of drawings]

FIG. 1 is a block diagram of a moving image recording / reproducing apparatus that is an embodiment of the present invention.

FIG. 2 is a schematic pattern diagram for explaining the same encoding method.

FIG. 3 is a schematic pattern diagram for explaining a recording method on the recording medium.

FIG. 4 is a schematic pattern diagram for explaining a conventional encoding method.

FIG. 5 is a schematic pattern diagram for explaining a recording method on the recording medium.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 A / D converter 2 Divider 3-6 Encoder 7 Recording processing part 8-11 Memory 12 Code sequence multiplexer 13 Recording signal processor 14 Recording / reproducing head 15 Optical disk 16 Reproduction processing part 17 Reproduction signal processor 18 Code Column divider 19-22 memory

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Satoshi Kondo 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Ryota Hata, 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (2)

[Claims] 1. A divider for dividing a field or frame of an input moving image signal divided into a plurality of groups into N (N> 1, N is an integer), and the divided N image components in a field. Alternatively, N is coded using both the intraframe coding process and the interfield or interframe coding process.
Number of encoders and code strings output from the N encoders are divided into M (M> 1, M is an integer) divided code strings having a size of at least one sector of a disk having a sector structure. The N number of memories to be divided into N and the N × M number of division code strings output from the memory are the m-th division code sequence of the nth code sequence in the N × M number of division code sequences. The (n,
The (m) -th (1 ≦ n ≦ N, 1 ≦ m ≦ M, and n and m are integers) division code string is represented as (1, 1), (2,
1), ..., (N, 1), (1,2), (2,2),
..., (N, 2), ..., (1, M), (2,
M), ..., (N, M) in order, and the code string obtained by the code string multiplexer is recorded on the disk in order from a predetermined sector. A moving image recording / reproducing device. 2. A video disc having concentric or spiral tracks, on which sectors separated by a predetermined length are provided, and a digital signal including a moving image signal is recorded. The moving image signal is divided into a plurality of groups, divided into N (N> 1, N is an integer) for each frame, and the N divided image components are subjected to intra-field or intra-frame encoding processing and inter-field or N code strings obtained by coding using both the inter-frame coding processing are M (M> 1, where M is at least one sector capacity).
(M is an integer) divided into N × M divided code strings obtained by dividing the divided code string, and the m-th divided code string of the n-th code string in the N × M divided code strings is (N, m) th (1
.Ltoreq.n.ltoreq.N, 1.ltoreq.m.ltoreq.M, and n and m are integers, and are represented as (1,1), (2,1) ,.
(N, 1), (1, 2), (2, 2), ..., (N,
2), ..., (1, M), (2, M), ...,
A video disk characterized by being arranged in each sector in the order of (N, M).