JP3339271B2 - Compressed image data recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compressed image data recording apparatus for recording a video signal encoded with high efficiency.

[0002]

2. Description of the Related Art In recent years, technological development of high-efficiency coding has become active. High-efficiency coding is a coding method for reducing the redundancy of a video signal, and a commonly used method is coding using motion compensation using temporal redundancy. This technique called motion compensation is a method of reducing the information amount of a difference signal between frames by obtaining and correcting the motion between frames. When encoding a moving image with high efficiency, it is common practice to perform orthogonal transformation on data obtained by performing motion compensation.

[0003] There is also called variable-length coding performed using characteristics of data obtained by performing transform coding or motion compensation. Usually, the variable-length coding is performed for each orthogonal transform block and recorded or transmitted in units of a plurality of orthogonal transform blocks. Variable-length coded data is likely to be unrecoverable if an error occurs.Therefore, for each fixed recording data period, address information indicating which orthogonal transformation block the data is for is recorded. And take countermeasures against errors.

[0004]

However, in the above-mentioned conventional configuration, there is a problem that the amount of data for video information is reduced because the address information is recorded, and the compression efficiency of the video signal is reduced.

[0005] Furthermore, at the time of high-speed reproduction, necessary for the screen configuration,
Since the position on the tape of the highly efficient encoded data in the frame is not specified, there is a problem that the data cannot be used.

Further, when considering a mode in which the compression ratio is increased, there is a problem that a track on which data is not recorded is generated in a track to be recorded because the data amount is reduced.

[0007] Further, when encoding using motion compensation, if the first frame to be encoded is in the bidirectional prediction mode, if edited, motion compensation is not performed normally and the image quality is greatly degraded. There was a problem.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and it is an object of the present invention to provide a compressed image data recording apparatus that performs high-efficiency encoding between a plurality of frames and records data effectively.

[0009]

In order to achieve this object, a first aspect of the present invention is to create compressed data by efficiently encoding image data of consecutive N (N is an integer of 1 or more) frames as a GOP. And a recording area for recording the compressed data is divided into N picture areas and one insignificant data area, and data corresponding to each frame in the compressed data is divided into each frame in the GOP. First arranging means for arranging compressed data that could not be arranged by the first arranging means in a free area or an insignificant data area of the picture area, and first arranging means. Recording means for recording data of the recording area arranged by the second arrangement means on a predetermined number of tracks on the tape.

In order to achieve this object, a second aspect of the present invention is a high-efficiency encoding means for efficiently encoding image data of continuous N (N is an integer of 1 or more) frames as a GOP to generate compressed data. First arranging means for dividing a recording area for recording compressed data into N picture areas, and arranging data corresponding to each frame in the compressed data in a picture area corresponding to each frame in the GOP. A second arranging means for arranging compressed data which could not be arranged by the first arranging means in an empty area of a picture area; And recording means for recording data on the track (1).

In order to achieve this object, a third aspect of the present invention is a high-efficiency encoding means for efficiently compressing image data of continuous N (N is an integer of 1 or more) frames as a GOP to generate compressed data. The recording area for recording the compressed data is divided into N picture areas, one insignificant data area, and one data area, and the compressed data corresponding to each frame in the compressed data is stored in each GOP in the GOP. First arranging means for arranging compressed data which cannot be arranged by the first arranging means in a picture area corresponding to a frame, second arranging means for arranging compressed data which cannot be arranged by the first arranging means in an empty area of the picture area or an insignificant data video area; 3rd recording audio signal to
It is characterized by comprising an arranging means and a recording means for recording data of the recording area arranged by the first arranging means, the second arranging means and the third arranging means on a predetermined number of tracks on the tape.

According to a fourth aspect of the present invention, there is provided a high-efficiency encoding means for efficiently compressing image data of continuous N (N is an integer of 1 or more) frames as a GOP to generate compressed data. Recording means for recording compressed data in recording blocks on a predetermined number of tracks on a tape and recording a frame number to be recorded in the recording block as a code indicating a relationship between the GOP and the predetermined number of tracks. It is characterized by:

According to a fifth aspect of the present invention, in order to achieve this object, the head frame is bidirectionally encoded when the image data of consecutive N frames (N is an integer of 1 or more) is encoded as one unit at a high efficiency. When performing high-efficiency coding by prediction, a high-efficiency coding unit that has a mode of performing high-efficiency coding only by backward prediction and creates compressed data by high-efficiency coding is provided. Recording means for recording in a recording block on a track.

[0014]

With the above arrangement, the compressed image data recording apparatus according to the first aspect of the present invention can record a frame in a GOP at a predetermined position on a tape to be recorded. Efficiency is improved. further,
Since the position on the tape of the highly efficient encoded data is specified in the frame, high-speed reproduction is also possible. With the above configuration, the compressed image data recording device of the second aspect of the present invention
The same effect as the first invention can be realized by a different recording format.

With the above arrangement, the compressed image data recording apparatus according to the third aspect of the present invention can record data for high-speed reproduction in an empty area on a track, and can record all data even in a mode with a high compression ratio. Trucks are available.

With the above arrangement, the compressed image data recording apparatus according to the fourth aspect of the present invention can easily associate a recording block that can be reproduced during high-speed reproduction with intra-frame encoded data.

With the above arrangement, the compressed image data recording apparatus according to the fifth aspect of the present invention performs only backward prediction when the first frame to be encoded in the case of performing encoding using motion compensation is in the bidirectional prediction mode. Since encoding is performed, editing can be performed without deteriorating image quality.

[0018]

【Example】

Embodiment 1 Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a compressed image data recording apparatus according to the present embodiment. Reference numeral 101 denotes an input terminal for inputting a video signal; 102, a high-efficiency encoder for encoding an input video signal with high efficiency; Is the first in highly efficient encoded data
, A second arrangement unit for performing a second arrangement on highly efficient coded data, 105 a memory in which the first and second arrangement units arrange data, 106
Is a recorder for recording the data on the memory onto the magnetic tape, 1
Reference numeral 07 denotes a magnetic tape.

The operation of the compressed image data recording apparatus configured as described above will be described. Input terminal 101
In the high efficiency encoder 102, the input video signal is subjected to high efficiency encoding, for example, using two consecutive frames as GOPs to create and output compressed data.

Here, it is assumed that two frames in a GOP are composed of an I frame to be encoded by intra-frame processing and a B frame to be encoded by obtaining a difference between frames by performing bidirectional motion compensation.

First placer 103 and second placer 104
Arranges the input compressed data in the memory area in the memory 105 in the following procedure. FIG. 2 is a diagram showing a memory area in the memory 105. The memory area is divided into two picture areas and one insignificant data recording area. The first arranging unit 103 first records the compressed data corresponding to the I frame in the GOP in the I frame recording area of the picture area, and then records the compressed data corresponding to the B frame in the B frame recording area of the picture area. The compressed data that could not be recorded is output to the second mapper.

The second arranging unit arranges the input data in a non-duplicate data recording area or a free area of a picture area. GO
After placing all the compressed data for P in memory 105, recorder 106 records the data in 105 on a predetermined number of tracks. FIG. 2 shows that recording is performed on 20 tracks, and 135SB in the figure indicates the number of SBs which are recording areas on one track. In this case I
The format is such that a frame is recorded at 1350 SB and a B frame is recorded at 450 SB.

As described above, in the first embodiment, the frames in the GOP can be arranged so as to be recorded at the predetermined positions on the tape by the first arrangement unit 103. Signal compression efficiency is improved. Further, since the I-frame data which has been efficiently encoded in the frame is recorded at a predetermined position on the tape, high-speed reproduction is also possible.

In this embodiment, the GOP is performed with two frames. However, the number of frames is arbitrary, and it is also possible to use a P frame which performs one-way motion compensation for coding.

The input signal and the number of tracks to be recorded are arbitrary, and the ratio between the picture area and the non-important data recording area and the position on the track are arbitrary. The first
The placement device and the second placement device can be realized by one circuit, and other configurations are also possible.

(Embodiment 2) A second embodiment of the present invention will be described below with reference to the drawings.

Since the second embodiment is a case where the recording format on the tape of the first embodiment is changed, the circuit configuration of the compressed image data recording apparatus is the same as that of FIG. It is only the function of the deployer and the second deployer.

Hereinafter, the operation of the first placer and the second placer in the present invention will be described. The same high-efficiency coded compressed data as in the first embodiment is sent to the first
In the present embodiment, the arranging unit 104 arranges the input compressed data in the memory area in the memory 105 according to the following procedure. FIG. 3 is a diagram showing a memory area in the memory 105. The memory area is divided into two picture areas.

As in the first embodiment, the first arranging unit 103 first records the compressed data corresponding to the I frame in the GOP in the I frame recording area of the picture area, and then compresses the compressed data corresponding to the B frame into the picture. The data is recorded in the B frame recording area of the area, and the compressed data that could not be recorded is output to the second arrangement unit. The second arranging unit arranges the input data in an empty area of the picture area. Subsequent processing is the same as in the first embodiment.

FIG. 3 shows a format in which an I frame and a B frame are recorded in 1350 SB.

As described above, in the second embodiment, the same effect as in the first embodiment can be realized in another format.

In this embodiment, the GOP is performed with two frames. However, the number of frames is arbitrary, and it is also possible to use a P frame to be encoded by performing one-way motion compensation.

The input signal and the number of tracks to be recorded are arbitrary, and the ratio between the picture area and the non-important data recording area and the position on the track are arbitrary.

It should be noted that the first placer and the second placer can be realized by one circuit, and other configurations are also possible.

(Embodiment 3) Hereinafter, a third embodiment of the present invention will be described with reference to the drawings.

FIG. 4 is a block diagram of a compressed image data recording apparatus according to the present embodiment. Reference numeral 401 denotes an input terminal for inputting a video signal, 402 denotes a high-efficiency encoder for encoding an input video signal with high efficiency, and 403. Is the first in highly efficient encoded data
404 is a second allocator that performs a second allocation on highly efficient coded data, 405 is an audio signal allocator that allocates audio signals, and 406 is a first and a second allocation. 407 is a memory for storing data on the memory, 407 is a recorder for recording data on the memory on a magnetic tape, and 408 is a magnetic tape.

The operation of the compressed image data recording apparatus configured as described above will be described. Input terminal 401
The high-efficiency encoder 402 performs high-efficiency encoding of the input video signal in the same manner as in the first embodiment. The first arranging unit 403, the second arranging unit 404, and the audio signal arranging unit arrange the input compressed data and the audio signal in the memory area in the memory 406 in the following procedure.
FIG. 5 is a diagram showing a memory area in the memory 406. The memory area is divided into two picture areas, one insignificant data recording area, and one data area.

The arrangement of the compressed data in the first arrangement unit 403 and the second arrangement unit 404 is the same as in the first embodiment. The audio signal arrangement unit 405 records the audio signal in the data area. After placing all compressed data and audio signals for the GOP in the memory 406, the recorder
06 is recorded on a predetermined number of tracks.

FIG. 5 shows that recording is performed on 20 tracks, and 135SB in the figure indicates the number of SBs which are recording areas on one track. In this case, the format is such that the I frame is recorded at 1350 SB, the B frame is recorded at 450 SB, and the audio signal is recorded at 270 SB.

As described above, in the third embodiment, data can be recorded on all tracks even in a mode in which the compression ratio is higher than in the first and second embodiments. Furthermore, address reduction and high-speed reproduction are enabled as in the first and second embodiments.

In this embodiment, the GOP is performed with two frames. However, the number of frames is arbitrary, and it is also possible to use a P frame which is encoded by performing one-way motion compensation.

The input signal and the number of tracks to be recorded are arbitrary, and the ratio between the picture area, the non-important data recording area and the data area, and the position on the track are arbitrary.

It is of course possible to record data for high-speed reproduction in the data area, and it is also possible to record other data.

It should be noted that the first placer, the second placer, and the audio signal placer can be realized by one circuit, and other configurations are also possible.

(Embodiment 4) Hereinafter, a fourth embodiment of the present invention will be described with reference to the drawings.

FIG. 6 is a block diagram of the compressed image data recording apparatus according to the present embodiment. Reference numeral 601 denotes an input terminal for inputting a video signal, 602 denotes a high-efficiency coder for high-efficiency coding of the input video signal, and 603. Is the first in highly efficient encoded data
604 is a second layouter that performs a second layout on highly efficient encoded data, and 605 is a frame number that generates a frame number to be recorded in a recording block on a track of a magnetic tape. Generator, 606 is the first
And a memory in which the second arrangement unit arranges data; 607, a recording unit for recording data in the memory onto a magnetic tape;
8 is a magnetic tape.

The operation of the apparatus for recording compressed image data configured as described above will be described. Input terminal 601
The high-efficiency encoder 602 performs high-efficiency encoding of the input video signal in the same manner as in the first embodiment. The first arranging unit 603 and the second arranging unit 604 arrange data in the memory 606 as in the case of the first embodiment. The frame number adder 605 includes a sequence N as shown in FIG.
o. (Frame number) is added to the data in the memory area corresponding to the recording block on the track in accordance with the rate and the high efficiency coding method.

For example, in the case of FIG. 2, since IB / 25M corresponds, even numbers in the I frame recording area
The frame and the non-overlapping data recording area have odd numbers,
Each is added. First placer 603 and second placer 6
The data in the memory area which has been processed by the 04 and the frame number adder 605 is recorded on the magnetic tape 807 by the recorder 806.

As described above, in the fourth embodiment, the frame numbers are added by the frame number adding unit in units of blocks on the magnetic tape, so that the recording blocks that can be reproduced during high-speed reproduction are intra-coded. It is possible to easily determine whether the data is data, and it is possible to speed up decoding during high-speed reproduction. Further, the editing point is a point where the least significant bit (left column in FIG. 7) or the least significant 2 bits (right column in FIG. 7) of the sequence No. becomes 0, and can be easily found.

Note that the encoding pattern of FIG.
The rate and the number of recording tracks are merely examples, and there are other combinations.

(Embodiment 5) Hereinafter, a fifth embodiment of the present invention will be described with reference to the drawings.

FIG. 8 is a block diagram of a compressed image data recording apparatus according to the present embodiment. Reference numeral 801 denotes an input terminal for inputting a video signal; 805, a high-efficiency encoder; and 802, mode determination for determining an encoding method. Device 803 is a mode determination device 802
A motion detector that changes the method of motion detection according to the signal from
Reference numeral 804 denotes an encoder that changes the encoding method according to the information from the motion detector 803, 806 denotes a recorder that records highly efficient encoded data, and 807 denotes a magnetic tape.

The operation of the above-described compressed image data recording apparatus will be described. Input terminal 801
Video signal (hereinafter referred to as G
OP) is input to the high-efficiency encoder 805. The high-efficiency encoder 805 performs encoding by the following method. In the mode determiner, three normal modes of intra-frame coding, bidirectional motion prediction coding, and unidirectional motion prediction coding are performed.
A total of four types of modes are determined for each frame in the GOP, with a mode in which only backward prediction is performed when the first frame of the GOP is encoded by bidirectional motion prediction encoding. The motion detector obtains a motion vector according to each coding method except for intra-frame coding according to the determination of the mode determiner 802. The encoder 804 performs encoding using the motion vector obtained by the motion detector 803. The data that has been encoded with high efficiency as described above is stored in the recorder 8.
06 and recorded on the magnetic tape 807.

As described above, in the fifth embodiment, a mode in which only the backward prediction is performed when the head frame of a GOP is coded by bidirectional motion prediction coding is added to the mode decision unit 803, whereby motion compensation is performed. When the first frame to be encoded when encoding is performed in bidirectional prediction mode, encoding is performed only by backward prediction, so that image quality is not impaired even if the first frame at the time of editing is bidirectional prediction. You can edit with.

[0056]

As described above, according to the compressed image data recording apparatus of the present invention, a high-efficiency code for generating compressed data by performing high-efficiency coding of image data of consecutive N frames (N is an integer of 1 or more) as a GOP. Means for dividing the recording area for recording the compressed data into N picture areas and one insignificant data area, and converting data corresponding to each frame in the compressed data into a picture corresponding to each frame in the GOP. First arranging means for arranging compressed data that cannot be arranged by the first arranging means in a free area or an insignificant data area of a picture area; first arranging means; and second arranging means. Recording means for recording the data of the recording area arranged by the means on a predetermined number of tracks on the tape, so that the frames in the GOP can be
Since it can be arranged to record at a predetermined position on the tape,
There is no need to record address information, and the compression efficiency of the video signal is improved.

Further, since the data of the I frame which has been efficiently coded in the frame is recorded at a predetermined position on the tape, high speed reproduction is also possible.

[Brief description of the drawings]

FIG. 1 is a block diagram of an image compression data recording apparatus according to first and second embodiments of the present invention.

FIG. 2 is an explanatory diagram of a recording area in the first and fourth embodiments of the present invention.

FIG. 3 is an explanatory diagram of a recording area according to a second embodiment of the present invention.

FIG. 4 is a block diagram of an image compression data recording device according to a third embodiment of the present invention.

FIG. 5 is an explanatory diagram of a recording area according to a third embodiment of the present invention.

FIG. 6 is a block diagram of an image compression data recording apparatus according to a fourth embodiment of the present invention.

FIG. 7 is a diagram showing an example of codes recorded in a fourth embodiment of the present invention.

FIG. 8 is a block diagram of an image compression data recording device according to a fifth embodiment of the present invention.

[Description of Code] 101, 401, 601, 801 Input terminal 102, 402, 602, 805 High-efficiency encoder 103, 403, 603 First placer 104, 404, 604 Second placer 105, 406, 606 Memory 106, 407, 607, 806 Recorder 107, 408, 608, 807 Magnetic tape 405 Audio signal locator 605 Frame number adder 802 Mode determiner 803 Motion detector 804 Encoder

────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Kazuhiro Waki 1006 Kazuma Kadoma, Kazuma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-4-298802 (JP, A) (58) Surveyed fields (Int.Cl. ⁷ , DB name) H04N 5/76-5/956 H04N ^7/ 24-7/68

Claims (5)

(57) [Claims] 1. High-efficiency encoding means for producing compressed data by performing high-efficiency encoding using image data of continuous N (N is an integer of 1 or more) frames as a GOP, and a recording area for recording the compressed data being N First arranging means for dividing the image data into one picture area and one insignificant data area, and arranging data corresponding to each frame in the compressed data in the picture area corresponding to each frame in the GOP; A second arranging means for arranging the compressed data which cannot be arranged by the first arranging means in a free area of the picture area or the non-important data area; and wherein the second arranging means arranges the compressed data by the first arranging means and the second arranging means. Recording means for recording data in a recording area on a predetermined number of tracks on a tape. 2. High-efficiency encoding means for producing compressed data by performing high-efficiency encoding on image data of N (N is an integer of 1 or more) consecutive frames as a GOP; First allocating means for dividing data corresponding to each frame in the compressed data into the picture area corresponding to each frame in the GOP; Second arranging means for arranging the uncompressed compressed data in an empty area of the picture area; and recording data of the recording area arranged by the first arranging means and the second arranging means on a predetermined number of tracks on a tape. A compressed image data recording apparatus, comprising: 3. High-efficiency coding means for generating compressed data by performing high-efficiency coding using image data of continuous N (N is an integer of 1 or more) frames as a GOP, and setting a recording area for recording the compressed data to N Divided into one picture area, one insignificant data area, and one data area, and data corresponding to each frame in the compressed data is arranged in the picture area corresponding to each frame in the GOP. A first arranging unit; a second arranging unit for arranging the compressed data that could not be arranged by the first arranging unit in a free area of the picture area or the non-important data video area; A third arranging means for recording, and the data of the recording area arranged by the first arranging means, the second arranging means and the third arranging means are recorded on a predetermined number of tracks on a tape Recording means for recording the compressed image data. 4. The apparatus according to claim 3, wherein said third arranging means records image data for trick-play in said data area.
The compressed image data recording device according to the above. 5. N consecutive frames (N is an integer of 1 or more)
When performing high-efficiency encoding using the image data of
When the first frame is highly efficient encoded by bidirectional prediction
Has a mode to perform high-efficiency coding only with backward prediction,
High efficiency coding to create compressed data by high efficiency coding
Means for recording the compressed data on a predetermined number of tracks on a tape
Recording means for recording in a block.
Compressed image data recording device.