JPH0851591A - Optical disk and its reproduction method - Google Patents

Abstract

PURPOSE:To provide the optical disk and its reproduction method in which the data arrangement enables smooth fast feed reproduction or inverse reproduction of data even in the case where 2-dimensional compression codes and 3-dimensional compression codes are mixed in an optical disk device which compresses and records a digital image. CONSTITUTION:I-picture data reproduced into a video image singly are divided into I-picture data 60, 62, 64,... divided in the area of screen in the data arrangement of video signals. Smooth fast speed reproduction is attained from the I-picture data 60, 62, 64,... in the pattern division by deviating the arrangement of the data for each GOP, edit unit, in the special reproduction mode. Furthermore, the I-picture data are divided by a frequency at DCT coding or divided through gradation with a different number of picture elements and a different number of lines.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disc and a method for reproducing the optical disc.

[0002]

2. Description of the Related Art FIG. 17 is a block circuit diagram of a conventional optical disk recording / reproducing apparatus disclosed in Japanese Patent Application Laid-Open No. 4-114369. Reference numeral 1 denotes an A / A for converting a video signal, an audio signal or the like into digital information. D converter, 2 is information compression means, 3 is frame sector conversion means for converting the compression information into sector information equal to an integral multiple of a frame period, 4
Is an encoder, 5 is a modulator for converting into a predetermined modulation code in order to reduce inter-code interference in the recording medium, 6 is a laser drive circuit for modulating laser light according to the modulation code, and 7 is a laser output switch. Is.

Further, 8 is an optical head for emitting the laser beam, 9 is an actuator for tracking the light beam emitted from the optical head 8, 10 is a traverse motor for sending the optical head 8, and 11 is Optical disc 1
A disk motor for rotating the motor 2, a motor drive circuit 19 and a motor control circuit 20. Further, 13 is a reproduction amplifier for amplifying the reproduction signal from the optical head 8,
Reference numeral 14 is a demodulator for obtaining data from the recorded modulated signal, 15 is a decoder, 16 is a frame sector inverse transforming means, 17 is information decompressing means for decompressing the compressed information, and 18 is decompressed information. For example, it is a D / A converter for converting into an analog video signal or an audio signal.

FIG. 18 shows a moving picture standardized for compressing digital moving picture information and transmitting / storing it.
icturecoding Experts Group (hereinafter "MPEG")
Is a simplified representation of the data array structure (layer structure). In the figure, reference numeral 21 denotes a Group of Picture (hereinafter, “GO
P ”), 22 is a GOP layer composed of several pictures (screens), 23 is a slice obtained by dividing one screen into several blocks, 24 is a slice layer composed of several macroblocks, 25 Is a microblock layer, and 26 is a block layer composed of 8 pixels × 8 pixels.

In the MPEG system, for example, the microblock layer 25 has a minimum coding unit of 8 × 8.
This block is composed of pixels, and this block is a discrete cosine transform (hereinafter referred to as "DC
"T"). At this time, adjacent 4
One Y signal block, one Cb block positionally corresponding to these Y signal blocks, and one Cr block, totaling six blocks, are called macroblocks. A slice is formed by collecting a plurality of these macroblocks. A macroblock is the minimum unit of motion compensation prediction, and a motion vector for motion compensation prediction is performed in macroblock units.

FIG. 19 is a diagram showing an encoding structure when 17 screens are set to 1 GOP. In the figure, 27 is an I-picture which is video information for performing intra-frame DCT, and 28 is temporally positioned before and after. A B-picture for which DCT coding has been performed with motion compensation using the I-picture and P-picture as reference screens, and 29 is a DC for motion compensation in the forward direction.
It is a P-picture which is video information by T coding. 20 is a diagram showing the coding structure when 10 screens are 1 GOP, and FIG. 21 is a diagram showing the coding structure when 15 screens are 1 GOP. In the drawing, P
-P for picture, B-picture, and I-picture
Or P-picture, B or B-picture, I or I-p
Expressed as icture.

Next, the conventional operation will be described with reference to the drawings.
As the compression technique of digital video information advances, the above-mentioned compression information is recorded on the optical disc, so that the conventional VTR
It is possible to realize a video filing apparatus which has excellent searchability and is extremely easy to use as compared with a tape medium represented by the above. Further, since such a disk file device handles digital information, there is no dubbing deterioration as compared with the case of recording an analog video signal, and since it is an optical recording / reproducing system, a non-contact and highly reliable system can be realized.

Conventionally, when recording such compressed moving picture information on an optical disc, an optical disc recorder as shown in the block diagram of FIG.
Digitally compressed moving image information such as that of the EG system is recorded. At this time, the video information digitized by the A / D converter 1 is processed by the information compression means 2 into, for example, MP.
It is converted to a standard compressed moving image method such as the EG method. This compressed information is encoded and modulated to reduce the influence of intersymbol interference on the disc,
Recorded in. At this time, for example, the amount of data in each GOP unit is set to be approximately the same amount, and the GOP is divided into sectors equal to an integral multiple of the frame period to
It is clear that editing etc. is possible in units.

During reproduction, the optical disk 12
The video information recorded in is amplified by the reproduction amplifier 13,
After being restored to digital data by the demodulator 14 and the decoder 15, it is restored as pure video original data by removing the data such as address and parity by the frame sector inverse conversion means 16. Further, the information decompression means 17 reproduces it as a video signal by performing MPEG decoding, for example.
The / A converter 18 enables display on a monitor or the like.

As described above, when the MPEG method is used as the digital moving image compression method, the method shown in FIGS.
As shown in FIG. 1, DCT encoding is performed with motion-compensated I-picture 27 by intra-frame DCT and the above-described I-picture and P-picture located temporally before and after B- The coding structure in which the picture 28 and the P-picture 29, which is the video information by the DCT coding for motion compensation in the forward direction, are combined, is recorded in the disc as it is.

At this time, since the I-picture is subjected to the intra-frame DCT, it is possible to reproduce the image by this information alone, but the P-picture is subjected to the motion compensation in the forward direction. The image can be reproduced only after reproducing the I-picture. Further, the B-picture is a prediction screen from both directions, and therefore has a feature that it cannot be reproduced until after the preceding and following I-pictures or P-pictures are reproduced. In this case, naturally, the B-picture for which bidirectional prediction is performed has the smallest data amount and the coding efficiency is good.

However, since this B-picture cannot be reproduced independently, an I-picture and a P-picture are required.
If the number of B-pictures is increased accordingly, the buffer memory amount in the processing circuit increases and the delay time from data input to video reproduction increases. But,
In storage media such as optical disks,
An encoding method having a high compression efficiency is desired for long-term recording, and the delay time of the video reproduction does not cause a problem so that the encoding methods shown in FIGS. 19 to 21 are suitable.

Next, when the data having such an encoding structure is recorded on the disc, how the image retrieval and the high speed reproduction are performed is as follows. Figure 21
In the case of having the encoding structure as shown in (3), high-speed reproduction is possible by reproducing in I-picture units. In this case, a track jump is performed immediately after reproducing the I-picture, and the next or previous GOP is accessed, and the I-picture is reproduced there. By repeating such operations, it is possible to realize high-speed feed reproduction and return reproduction in which the feed speed is limited to an integral multiple of 15 times speed in FIG. 21 and 10 times speed in FIG.

However, in the actual image retrieval, if it is too fast, it will be difficult for the human eye to recognize it, and in order to confirm almost an image scene, the above-mentioned high-speed retrieval of 10 times or more is appropriate. In the case of searching for a detailed video point after performing the scene search of, it is necessary to perform fast-forward and reverse playback at several times speed. Therefore, it is clear that a wide range of special reproduction from several tens of times to several times of speed is required for effective video retrieval. However, in practice, for example, when compressed data of the MPEG system is used, if a P-picture is reproduced in the coding structure of FIGS. 19 to 21, the B-pictures up to that point are also reproduced. In practice, it was difficult to realize 4 to 8 times speed.

[0015]

Since the coding structure as described above is recorded on the disc as it is, when special reproduction is performed, reproduction can only be performed in I-picture units. Therefore, fast-forwarding or rewinding reproduction is possible only at a speed corresponding to the number of frames included in 1 GOP or an integral multiple thereof.

Further, in the digital video recording format shown in the conventional example, since the array of I-pictures, P-pictures, and B-pictures are arranged in order on the time axis, the special reproduction method is The method is limited to the following.

Particularly, in the conventional system for recording a digital moving image, the most basic special reproduction method is a special reproduction method using the information recorded in the TOC area at the innermost circumference of the disc. . in this case,
According to the start address of the scene change recorded in the TOC area and the start address of the video file, the digital moving image video of the I-picture stored at the above address is read and special reproduction is possible by sequentially reproducing it. .

The read operation of the optical disk in this case is shown in FIG.
It is represented by the flowchart in FIG. This flowchart shows a case where special playback is performed based on the address of the scene start portion of the moving image information recorded in the TOC area at the innermost circumference of the disc. First, the TOC area is jumped to and the scene start address is jumped. Is stored in the internal memory, the above address jump is performed, the I-picture in the jumped GOP is reproduced and displayed on the screen, and the operation of moving to the next jump destination address is repeated.

However, in such a method, a large amount of search destination addresses must be stored in the TOC, and the TOC information must be rewritten each time it is recorded.

In addition, during the special reproduction, if the P-picture is also reproduced, it is necessary to skip the data of the B-picture, but actually, the I-picture, the B-picture, or the P-picture.
Since the pictures are sequentially recorded on the disc, it may be impossible to reproduce the P-picture without waiting for rotation when a track jump is performed.

Further, since the data amount of the I-picture coded by the intra-frame DCT is larger than that of other P-pictures and B-pictures, in order to perform super high speed reproduction of several tens of times, There was a problem that it could not be realized because the data input time was insufficient.

When a desired GOP is searched from an arbitrary position on the disk, several times are required to search the head position of each GOP (generally, the time code and address of video image are recorded). There was a problem that the search operation of was required.

Further, during special reproduction, since only a part of the data in each GOP can be read, there is a problem that the video cannot be reproduced or only a part of the screen can be reproduced.

[0024]

In the optical disc according to the first aspect of the present invention, the digital video information is an intra-frame DCT.
I-picture data, which is video information for performing motion compensation, and P-, which is video information by DCT encoding for motion compensation in the forward direction.
A unit of several to several tens of frames in which picture data and B-picture data that is DCT-encoded with motion compensation using the above-mentioned I-picture data and P-picture data that are temporally preceding and succeeding as a reference screen are mixed. Of consecutive video information blocks, the I-picture data is divided into divided I-picture data for each area divided on the video screen and arranged in the video information block, and adjacent recording tracks are adjacent to each other. The divided I-picture data in the video information block is arranged differently, and a header signal or a parity signal is recorded before each divided I-picture data.

The optical disk according to the invention of claim 2 is DC
The T-coded I-picture data is divided into a plurality of sub-blocks divided from data close to direct current having a frequency in the horizontal and vertical directions of the video screen to high-frequency data, and video information adjacent to each other on adjacent recording tracks. A header that indicates the frequency component data in which the contents of the sub-block are located before the sub-blocks, in which the sub-blocks of the I-picture, P-picture, and B-picture data of the block are arranged in reverse order. Alternatively, the parity signal is recorded.

An optical disk according to a third aspect of the present invention is the optical disk according to the second aspect, wherein the DCT-encoded I
-The picture data is divided into a plurality of sub-blocks divided from data close to direct current of horizontal and vertical frequencies of the video screen to high-frequency data, and each frequency division in adjacent video information blocks of adjacent recording tracks. I-
The arrangement is such that the arrangement of picture data is different, and a header or a parity signal that indicates which frequency component data the content of the sub-block is recorded is recorded before each sub-block.

In the optical disc according to the invention of claim 4, the digital video information is an I-picture which is video information for performing intra-frame DCT and a P-picture which is video information by DCT coding for performing forward motion compensation. Then, DCT coding is performed with motion compensation using the above-mentioned I-picture and P-picture located temporally before and after as a reference screen.
-A combination of a number of pictures and a series of video information blocks in units of several tens of frames, and by combining the digital moving image video information with lower layer data having a small number of pixels and a small number of lines The data is divided into upper layer data from which an image with a large number of lines and a large number of lines can be obtained, and the arrangement of the lower layer data and the upper layer data is sequentially switched, and the type of the data block is recognized before each data block. Claim 5 for
The optical disc according to the present invention is the optical disc according to claim 1, claim 2 or claim 4, wherein the data arrangement order of I-picture, P-picture and B-picture in the video information block is adjacent to each other. The video information blocks are arranged differently.

An optical disc according to a sixth aspect of the present invention is the optical disc according to the first, second or fourth aspect, wherein the I-picture data is screen division data, frequency division data, the number of pixels and lines. A discrimination signal indicating whether the division is performed by the number is written at the head of each video information block.

An optical disc according to a seventh aspect of the present invention is the optical disc according to the first, second or fourth aspect, in which the head positions of the respective digital video information blocks are recorded aligned in the radial direction of the optical disc. It is a thing.

According to an eighth aspect of the present invention, there is provided an optical disc reproducing method including a tracking actuator for tracking a scanning spot on a predetermined track, a tracking control circuit and a track jump circuit for performing interlaced scanning. In a device, a header signal or a parity signal recorded before each I-picture when performing high-speed special reproduction or reverse reproduction of the optical disc according to claim 1, 3 or 5. Based on the above, the jump operation is repeated to perform high-speed fast-forward reproduction and reverse reproduction.

According to a ninth aspect of the present invention, there is provided an optical disc reproducing method including a tracking actuator for tracking a scanning spot on a predetermined track, a tracking control circuit and a track jump circuit for performing interlaced scanning. When performing high-speed special reproduction or reverse reproduction of the optical disk according to claim 6 in the device, the track jump operation is repeated based on the discrimination signal written at the beginning of each video information block to achieve high speed. It is designed to perform fast-forward playback and reverse playback.

[0032]

According to the optical disk of the first aspect of the present invention, the screen division I-picture data can be sequentially reproduced by searching the header signal or the parity signal recorded before each screen division I-picture data. .

According to the optical disc of the second aspect of the present invention, the order of the sub-blocks of the frequency division I-picture, P-picture and B-picture data in the adjacent video information blocks of the adjacent recording tracks is exchanged. In addition to arranging, a header or a parity signal indicating which frequency component data the content of the sub-block is recorded is recorded before each sub-block. Therefore, by searching the header signal or the parity signal. The frequency division I-picture data can be sequentially reproduced.

According to the optical disc of the third aspect of the present invention, the frequency-division I-picture data in the adjacent video information blocks of the adjacent recording tracks are arranged so that the arrangement is different, and the sub-blocks Since the header or the parity signal indicating which frequency component data the contents of the sub-block is recorded before, the frequency division I is performed by searching the header signal or the parity signal and repeating the track jump. -High-speed fast-forward playback and reverse playback of picture data can be performed.

According to the optical disc of the fourth aspect of the present invention, by combining the digital moving image information with the lower layer data having a small number of pixels and the number of lines, and combining the lower layer data with the lower layer data, an image having a large number of pixels and lines can be obtained. While dividing into the obtained upper layer data, the lower layer data and the upper layer data are sequentially exchanged and arranged,
Since a header or parity signal for recognizing the type of the data block is recorded before each data block, digital moving image information can be sequentially reproduced by searching the header signal or parity signal. it can.

According to the optical disc of the fifth aspect of the invention, the I-picture, P-picture and B-picture in the adjacent video information blocks of the adjacent recording tracks are arranged so that the data arrangement order is different. Therefore, by searching the header signal or parity signal recorded before each of these data and repeating the track jump, high-speed fast-forward reproduction or reverse reproduction can be performed on the screen division I-picture data. it can.

According to the optical disc of the sixth aspect of the present invention, the recorded digital moving picture video information is sequentially reproduced by searching the discrimination signal written at the head of each video information block and discriminating its content. can do.

According to the optical disc of the seventh aspect, since the head positions of the respective digital video information blocks are recorded in alignment with the radial direction of the optical disc, the timing of the track jump can be accurately determined. .

According to the optical disk reproducing method of the eighth aspect of the present invention, the track jump is repeated based on the header signal or the parity signal recorded before each I-picture data, so that the I-picture data is divided. High speed special reproduction and reverse reproduction of digital video information can be performed.

According to the optical disc reproducing method of the ninth aspect of the invention, the type of data of each video information block can be discriminated based on the discrimination signal written at the head of each video information block. It is possible to reproduce existing digital video information.

[0041]

【Example】

Example 1. Next, a first embodiment of the present invention will be described. FIG. 1 is a diagram showing a data structure of a digital moving image of the first embodiment, FIG. 1 (a) is a diagram showing a structure of a GOP, and FIG. 1 (b) is a diagram showing an entire data array including audio data. is there. In the figure, 30 is a header indicating the start position of data, and 31 is a G indicating an address which is an editing unit for each GOP.
OP address, 32 is attribute data attached to the digital moving image data, 33 is an audio header indicating the start position of audio data 34, 35 is a video header indicating the start position of video data 36, and 37 is a P-picture 29
Is a P-picture header indicating the beginning position of the B-picture, and 38 is a B-picture header indicating the beginning position of the B-picture 28. In the drawings, P-picture, B-picture, and I-picture are referred to as P-picture, B-picture, and I-picture, respectively.
Express.

FIG. 2 is a diagram showing a detailed structure of the digital moving picture image data array of the first embodiment. Reference numeral 39 is a mirror surface portion for offset correction in the sample format walve pit or continuous guide groove system, and 40 is, for example, a constant zone angular velocity. Zone address on a rotation (CAV) type optical disc, 41 is a sector address which is an address of a sector into which a GOP is further divided, and 42 is a video G.
Video GOP address indicating an OP unit address, 43
Is video attribute data in which attribute data accompanying the digital moving image is recorded, 45 is an I-picture header indicating the start position of I-picture data, 46 is I-picture data, and 47 is an error correction code of I-picture data. The recorded I-picture ECC (error collection code),
48 is a P-picture header indicating the start position of the P-picture data, 49 is P-picture data, 50 is a scalability mode, 51 is the number of frames in a GOP, 52 is a GOP structure indicating the arrangement of IBP pictures in the GOP, etc. ,
53 is a data array and position in the I-picture, 54 is detailed attribute data such as presence / absence of pan / zoom / scene change, 55 is a time code, 56 is a jump destination address during special playback, 57 audio mode, and 58 is stationary. Image mode,
Reference numeral 59 is a spare area.

FIG. 3 is a block circuit diagram of a recording apparatus using the optical disc of the first embodiment. In the figure, 83 is an A / D converter for digitizing an analog moving image, 84 is a motion detector for detecting a motion vector of digital moving image information, and 85 is a vertical or horizontal direction of the digital moving image information. Discrete cosine transformer for decomposing into spatial frequencies of, 86 is an adaptive quantizer, 87 is an inverse quantizer, 88 is an inverse discrete cosine transformer for restoring the original video information from frequency components, and 89 is A frame memory that stores a reference image based on a motion vector, 90 is a variable-length encoder, 91 is a buffer memory, 92 is a format encoder for adding address information and attribute data, and 93 is an effect of intersymbol interference. For modulating the laser, 94 is a laser modulator for modulating the laser on the basis of the information from the modulation circuit 93, and 95 is a photo head of the optical head. Kas tracking servo circuit for performing a feed control, and disk motor control, 96 system controller, 9
Reference numeral 7 is an optical disk capable of recording by magneto-optical recording or phase change recording, 98 is an optical head, 99 is a feed motor, and 100 is a disk motor.

FIG. 4 is a diagram showing the detailed structure of the I-picture data recording portion of the optical disc. The video header 35 shows the head position of the video data of the n-track group.
Reference numeral 60 is divided data composed of a plurality of slices 23 in the upper 1/3 of the screen of the I-picture 27, and 61 is a start position of divided data 62 from the upper 1/3 to 2/3 of the I-picture 27 in the screen. , 63 is a sub-header indicating the start position of the divided data 64 composed of a plurality of slices 23 in the lower 1/3 of the screen of the I-picture 27,
48 is a P-picture header, 65 is the first P-picture data in the GOP, 66 is a header indicating the start position of the second P-picture data 67, 68 is n + 1 and n
A header indicating the start position of the entire digital moving image data of the +2 track group and indicating that it is also the start of the P-picture data. 69 is a portion 60 in which the data of the slice 23 in the upper 1/3 of the screen of the I-picture 29 is written. Is a header indicating the beginning position of the.

FIG. 5 is a flow chart showing the special reproduction operation of a moving picture in the optical disk device in the system in which the file structure of the digital moving picture video data is such that the screen is vertically divided into several slice units.

Next, the operation of the first embodiment will be described. General digital moving image data is shown in FIGS. 19 to 2 of the conventional example.
1, the I-picture 27, the B-picture 28,
The data of P-picture 29 is mixed. However, since the I-picture uses a two-dimensional compression method, it is possible to reproduce the video independently, but the P-picture cannot be restored until after the I-picture is reproduced, and the B-picture can be the I-picture and the P-picture. It can be restored only after playing the picture and. Therefore, as shown in FIG. 1, the data arrangement on the disc is such that the I-picture and the P-picture are consecutively arranged in the GOP and then the B-picture is arranged, which is suitable from the above-mentioned principle of signal processing. It is clear that

In this case, the audio data is also GO.
It is desirable to arrange in P units. As a result, GOP
It is possible to post-record and edit in units of. Furthermore, FIG.
As shown in FIG. 2, the data structure of is provided with a video GOP address 42 for enabling GOP unit editing and headers 45, 48 for indicating the start positions of I-picture and P-picture data. It is possible to take out the I-picture data independently and the P-picture independently.

By providing the area 43 in which the attribute data in the digital moving image is described, the scalability mode 50 showing whether or not the hierarchical structure corresponds to the number of pixels and the number of lines of the screen, and the frame in the GOP are displayed. A GOP indicating the number 51, the arrangement of I-picture data, B-picture data, P-picture data in the GOP, etc.
Since the structure 52 is provided, it is possible to support a plurality of signal processing methods. Also, by describing the I-picture data structure in the GOP structure 52, it is possible to describe in advance the arrangement corresponding to the trick play described below.

As described above, in the format in which I-pictures and P-pictures are continuously arranged in the GOP, it is possible to support special reproduction by further devising the data structure of I-pictures. It will be possible.
In this case, for example, as shown in FIG. 4, it is described that I-picture data is divided into upper and lower ranges 1/3 of the screen in slice units, and the file blocks corresponding to the above-mentioned parts on the screen are replaced in GOP units. . Such a data arrangement is obtained by using the buffer memory 91 and the format encoder 92 in the optical disk recording / reproducing apparatus shown in FIG.
It becomes possible by controlling with.

Further, in the file structure as shown in FIG. 4, in the zone CAV type disc format in which the head parts of GOPs are aligned in the disc radial direction, the track jump is performed as shown in the figure to divide the screen of the I-picture. It is possible to connect the created data and perform video reproduction of one screen in 3 GOPs. At this time, since partial continuous reproduction of I-pictures can be performed without generating too many rotation waits, the amount of data is different from that of other P-pictures or B-pictures.
In reproduction of I-picture data larger than a picture, for example, a fast-forward speed at fast-forward reproduction can be greatly increased.

Further, in the zone CAV type disc format, in order to align the GOP head data in the disc radial direction, the total amount of data per GOP is an integral multiple of one track (one round) or an integral multiple of 1/2 track. This can be achieved by allocating zones so that

The operation of the optical disk device at the time of the special reproduction described above is shown as an operation example as shown in the flowchart of FIG. First, when special playback starts, video G
The OP address is detected, and the time code or the like is displayed on the screen by, for example, a character generator or the like. Then G
The video attribute data in the OP is read to determine whether the I-picture structure is a screen division structure. In the case of the screen division method as shown in this embodiment, the header at the top of the screen of the I-picture is detected. Data reading, then track jump, then header detection and data reading at the center of the screen, and finally track jump further, header detection and data reading at the bottom of the screen. At this time, the screen data of the I-picture is connected by the image memory. By repeating the above operation until the special reproduction is completed, high-speed fast-forward and reverse reproduction are possible.

Even in the case of the CLV type optical disc, the data capacity of the I-picture is other B-picture or P-picture.
Although it is much larger than a picture, it is necessary to reproduce an I-picture first and then reproduce a P-picture or only an I-picture during special reproduction. The special reproduction ratio can be improved by adopting a method in which the I-picture data can be divided and reproduced, as compared with the conventional method in which all the data must be reproduced.

Example 2. Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 6 is a diagram showing the arrangement structure of the digital moving picture image data of the second embodiment, and 71 to 77 are DC.
It is a new file block when the block layer 26 of the digital moving image in T coding is divided into spatial frequencies as shown in FIG. Here, the closer to (a), the closer to the DC component, and the closer to (g), the closer to the high frequency region. In particular, FIG. 6 shows that the file structure in the I-picture in GOP units is divided into spatial frequency units in the DCT code, and the arrangement is switched for each GOP.

Further, FIG. 7 is obtained by further expanding the system of FIG. 6 so that the data array of I-pictures and P-pictures is GOP.
It was replaced every time. In the figure, reference numeral 80 is an I-picture header indicating the start position of the I-picture data.

FIG. 8 shows an example in which the number of P-pictures in one GOP is four. In the figure, 81 is the third P-picture.
A P3-picture header indicating the start position of the picture 78,
Reference numeral 82 indicates P4-, which indicates the start position of the fourth P-picture 79.
This is a picture header. FIG. 9 is a diagram showing a special reproduction operation in consideration of rotation waiting in the digital moving image data arrangement of FIG. FIG. 10 is a flowchart showing the operation of the optical disc drive when the I-picture data is divided by the frequency unit.

FIG. 11 is a diagram showing a data array on the zone CAV type optical disc when the sample servo type preformat is performed. In the figure, 123 is a header and servo pits, 124 is a sector address, 125 is audio data, and 126 is I.
-The sub-headers of the data blocks (a) to (c) in the picture, 127 is the I-picture data from (a) to (c) of the I-picture, and 128 is the header of the audio data. FIG. 12 is a diagram showing a data array on the disk in the continuous guide groove system.
In the figure, 129 is a mirror surface portion for detecting the offset of the tracking sensor when performing push-pull type tracking, and 130 is, for example, a 2-7 modulation type or 1-
This is a resync byte in the case of using a modulation system having an intermittent data structure such as the 7 modulation system.

Next, the operation of the second embodiment will be described with reference to the drawings. In a standard digital moving picture video compression method represented by MPEG, JPEG, etc., data obtained by zigzag scanning by dividing the spatial frequency in the DCT encoding in the macroblock 24 in the vertical and horizontal directions as shown in FIG. It has an array structure. For example, if the DCT encoded data of 63 pieces of I-picture data in the figure is decomposed in units of 9, it is possible to decompose into 7 blocks, for example, (a) to (g) in the figure. When recording data, these I-picture data are not arranged in units of slices 23, but are arranged in units of (a) to (g) as shown in the figure.
If a header signal, a parity signal, etc. are added to the head of a block divided in units of each frequency range, even if not all of the data of an I-picture, which has a relatively large amount of data during special reproduction, is reproduced, the DCT encoded data of a relatively large amount can be reproduced. An image can be obtained by reproducing only the data close to the DC component.

For example, when the optical disk has a zone CAV system configuration and the GOP head positions are aligned in the disk radial direction, as shown in FIG. 6, data blocks from (a) to (g) of the I-picture. By rearranging the data in units of GOPs, it is possible to continue reproducing only, for example, (a) in I-picture data without waiting for rotation by repeating the track jump. For example, for an existing CD size (12 cm diameter) optical disc, 2
Recording signals at 4 times the current CD rate with double linear density,
The disk rotation speed changes from about 600 rpm to 1200 rpm, and the worst (at 600 rpm) rotation waiting time reaches about three screens.

Therefore, if one GOP is composed of, for example, 15 screens, and if the I-picture can be read within the time corresponding to one screen (within 33 msec), the I-picture can be read.
It is possible to play back pictures continuously at 15 times speed, but if a rotation wait occurs, one rotation will take about 3 screens (10
(0 msec) is wasted, so the speed will be 5 times at maximum.

In order to prevent the reduction of the special reproduction magnification (n speed) as described above, if the method of skipping the next GOP and reproducing the I-picture of the next GOP is used, one image is displayed on 30 screens. , Same screen at 15x speed
It will be played back once, and the video during special playback will be extremely awkward. Moreover, if the number of skips increases, there is a risk of skipping a necessary scene.

In order to prevent awkwardness and skipped reading during such special reproduction, the reproduction data amount of the I-picture is reduced within the range where image recognition is possible, and low frequency components in DCT encoding of the I-picture, for example. It is possible to reduce the waiting time for rotation by making it possible to reproduce only the data, changing the arrangement for each GOP, and repeating the track jump.

Further, not only the reproduction of (a) of the I-picture data as shown in FIG. 6 but the recording of the digital moving image data as shown in FIG. By also performing the reproduction of the data block of (c) or (c), it is possible to perform finer video reproduction even during special reproduction. At this time, as shown in FIG. 7, not only the arrangements of (a) to (c) in the I-picture data are interchanged, but also the I-picture and the P-picture are interchanged, so that the rotation waiting time described above can be obtained. Special playback with less noise is possible. In this case, continuous data at the time of special reproduction can be obtained at least in units of 4 GOPs.

Further, as shown in FIG. 8, when the number of P-pictures per GOP is 4, the number of P-pictures is further set to 2 and the I-picture data is replaced with the I-picture data. It is possible to realize high-speed reproduction for reproducing (a) to (c). In this case, continuous data reproduction in units of at least 6 GOPs is possible.

In the case where the rotation waiting is permitted to some extent and the special reproduction at several times speed is performed, the track jump operation as shown in FIG. 9 is performed. At this time, if the track jump operation shown by the dotted line in the figure is performed, the I-picture (spatial frequency data from (a) to (c)) is reproduced in units of two GOPs, and shown by the solid line. If you perform such a track jump operation, one G
It becomes possible to reproduce an I-picture for each OP.

Actually, as shown in FIG. 9, since the data array in the I-picture is exchanged, the operation as shown by the solid line becomes possible, and the finer movement can be realized as compared with the case of the dotted line. Became.

When the special reproduction operation as described above is performed, the optical disk drive performs the operation shown in the flowchart of FIG. First, the head address of the GOP of digital moving image data is detected, and time information such as a time code is displayed on the screen.
Further, the video attribute data is read to determine whether or not the I-picture structure is frequency-divided. If the I-picture structure is frequency-divided, the header of the low-frequency part of the I-picture is searched first, and the I-picture low-frequency is searched. Part data is read and displayed as an image, a predetermined number of track jumps are performed, and the above operation is repeated until the special reproduction ends. In this way, special reproduction can be realized by sequentially reproducing data of only low frequency components in DCT encoding of I-picture.

In an optical disc having a sample servo system disc format, sectors having a header and servo pits 123 as one unit are aligned in the disc radial direction within a certain zone as shown in FIG. The data, P-picture data, audio data, etc. are completed by an integral multiple of the sector of the above sample servo format, so that
The data structure up to can be reproduced on the disc.

Also, an optical disk having a continuous guide groove type disk format can be dealt with by using a file structure on the disk as shown in FIG.
In this case, the file from the mirror surface portion 129 to the next mirror surface portion 129 is a large file unit.
The file structure is further subdivided by 0, and I-
By making the picture data, P-picture data, audio data, etc., an integral multiple of these subdivided file units, the data structure shown in FIGS. 6 to 9 can be reproduced on the disc. Above is the optical disc zone CA
In the case of the V format, it goes without saying that even in the case of the CLV format, the special reproduction ratio can be improved by frequency-dividing the I-picture as described above.

Example 3. Next, a third embodiment of the present invention will be described. FIG. 13 shows digital moving image compressed video information, for example, compressed information corresponding to 780 pixels × 480 lines and 360
It is hierarchized into two, that is, compressed information corresponding to 240 lines of pixels, and 780 pixels × 48 from this hierarchized information.
It is a block diagram showing a decoding circuit for restoring a video signal of 0 line. In the figure, 101 is a variable length encoder, 102 is an inverse quantizer, 103 is an inverse discrete cosine transform, 104 is a motion compensator, 105 is a frame memory, and 106 is a lower layer digital moving picture compressed video data. Is a decoder for.

FIG. 14 is a block diagram of an optical disk device for decoding digital compressed moving picture image information which is layered and recorded on the optical disk by using the decoding circuit shown in FIG. 13. In FIG. 14, 107 is recorded on the optical disk. A reproducing amplifier for reproducing the digital moving picture image information, 108 is a data detecting and PLL circuit for detecting data from the signal from the reproducing amplifier 107, 10
Reference numeral 9 is a header detection / data classification circuit for detecting a header signal in the data detected by the data detection circuit to classify the data, and 110 is an error correction circuit.

FIG. 15 is a diagram showing the arrangement of hierarchical I-picture and P-picture data on the disc.
111 is lower phase data of an I-picture corresponding to 360 pixels × 240 lines of digital moving image information, 112
Is 780 pixels × 480 together with the lower layer data 111.
The upper layer data of the I-picture for which the data t of the line is obtained, 113 is the header of the upper layer data 112, and 114 is P
-Lower layer data of picture, 115 upper layer data of P-picture, 116 header of upper layer data of P-picture, 117 lower layer data of second P-picture, 118 second P -Upper layer data in the picture, 119 is a header of the upper layer data in the second P-picture, 120 is a header of the upper layer data of the I-picture, 121 is a header in the upper layer data of the first P-picture , 122 are headers of lower layer data in the second P-picture.

FIG. 16 is a diagram showing a data arrangement on a disc in which only I-picture data is layered.

Next, the operation of the third embodiment will be described. In the MPEG system, which is being adopted as an international standard, the data structure is hierarchized, and the lower layer video data of 360 pixels × 240 lines and the upper layer video that can be combined with this data to obtain the data of 780 pixels × 480 lines. There is a method of dividing into data and. Such video data is shown in Figure 1.
By using the decoding circuit shown in FIG. 3, the upper layer data and the lower layer data can be combined to obtain a decrypted video screen of 780 pixels × 480 lines, which is the digital video image information of the upper layer.

With respect to the digital moving picture video data layered in this way, for example, when I-pictures and P-pictures are layered, it is possible to arrange the data on the optical disk as shown in FIG. In this case, the upper layer data and the lower layer data of the I-picture and P-picture are
Tracks are jumped at the time of special reproduction by arranging them separately by a header or the like and switching the arrangement of the above I-picture and P-picture in GOP units, for example, to continuously read only the lower layer data of the I-picture. You can

Further, as shown in FIG. 16, a case may be considered in which only I-pictures are hierarchized for the sake of simplicity. Even in this case, by exchanging the I-picture data and the P-picture data in GOP units, it is possible to continuously read the lower layer data of the I-picture during special reproduction. Generally, the amount of I-picture data is GOP.
Since it occupies a large area inside, if you try to read everything, you can not get a large magnification during special playback,
By reading only the lower layer data of I-pictures and P-pictures as described above, it is possible to increase the special reproduction ratio and increase the number of reproduction screen frames during special reproduction to reproduce smooth motion. Become.

FIG. 14 shows a block diagram of an optical disc recording / reproducing apparatus capable of restoring the hierarchical data as described above. First, the reproduction signal of the optical disk amplified by the reproduction amplifier 107 is detected as data by the data detector 108, and is divided into upper layer data and lower layer data by the header detection / data classification circuit 109. Video can be reproduced by correcting the separated data in each of the error correction circuits 110 and inputting to the decoding circuit for hierarchical data similar to that shown in FIG. In this case, in the case of only the lower layer data, the decoder 106 can obtain only an image of 360 pixels × 240 lines.

[0078]

According to the optical disc of the first aspect of the present invention, since the header signal and the parity signal are recorded at the head of the data obtained by dividing the I-picture data in screen area units, the I-picture in each GOP is recorded. When performing special playback in which only I-pictures are played back and joined together, it is not necessary to read all I-picture data, so the special playback magnification is improved and smooth continuous screen operation during special playback is possible. .

According to the optical disc of the second aspect of the present invention, the order of the sub-blocks of the frequency division I-picture, P-picture and B-picture data in the adjacent video information blocks of the adjacent recording tracks is exchanged. In addition to arranging, a header or a parity signal indicating which frequency component data the content of the sub-block is recorded is recorded before each sub-block. Therefore, by searching the header signal or the parity signal. Since I-picture data of a desired low frequency component can be arbitrarily accessed and sequentially reproduced, it is not necessary to read all I-picture data at the time of special reproduction if the resolution of the video screen is sacrificed to some extent. Special reproduction ratio is high, and smooth image reproduction can be obtained. Further, when the zone CAV format disc was used, the rotation waiting time during special reproduction was reduced.

According to the optical disc of the third aspect of the present invention, the frequency-division I-picture data in the adjacent video information blocks of the adjacent recording tracks are arranged so that they are arranged differently, and the sub-blocks are arranged in front of each sub-block. Since a header or a parity signal indicating which frequency component data is contained in the sub-block is recorded, the I-picture of the desired low frequency component is searched by searching the header signal or the parity signal. Since data can be accessed arbitrarily and played back sequentially, it is not necessary to read all the I-picture data at the time of special playback if the resolution of the video screen is sacrificed to some extent, and the special playback magnification is high and the video is smooth. Reproduction is obtained. Further, when the zone CAV format disc was used, the rotation waiting time during special reproduction was reduced.

According to the optical disc of the fourth aspect of the present invention, by combining the digital moving picture image information with the lower layer data having a small number of pixels and a small number of lines, and combining the lower layer data with the lower layer data, an image having a large number of pixels and a large number of lines is generated. While dividing into the obtained upper layer data, the lower layer data and the upper layer data are sequentially exchanged and arranged,
Since a header or a parity signal for recognizing the type of the data block is recorded before each of the data blocks, the header signal or the parity signal is searched to find I of a desired small number of pixels and lines.
-The digital moving image information can be played sequentially by accessing the picture data arbitrarily, and the image can be played without reading all the I-picture data during special playback. It became possible to take a high magnification.

According to the optical disc of the fifth aspect of the present invention, I-pictures, P-pictures and B-pictures in adjacent video information blocks of adjacent recording tracks are arranged so that the data arrangement order is different. Zone C
When the AV format disc format is used, the header signal or the parity signal recorded before each of these data is searched and the track jump is repeated to rotate the screen division I-picture data at high speed and fast forward without waiting for rotation. Playback and reverse playback can be performed.

According to the optical disc of the sixth aspect of the present invention, the I of the recorded digital moving image video information is obtained by searching the discrimination signal written at the head of each video information block and discriminating its content. -It is possible to determine whether the picture data is frequency division data, screen area division data, or pixel / line number division data.

According to the optical disc of the seventh aspect of the present invention, since the head position of each digital video information block is recorded in alignment with the radial direction of the optical disc, the timing of the track jump can be accurately determined. ,
It became possible to continuously read data during special playback without waiting for rotation.

According to the optical disc reproducing method of the eighth aspect of the present invention, the track jump is repeated based on the header signal or the parity signal recorded before each I-picture data for division. High speed special reproduction and reverse reproduction of digital video information can be performed.

According to the optical disc reproducing method of the present invention, the type of data of each video information block can be discriminated based on the discrimination signal written at the head of each video information block. It is possible to reproduce existing digital video information.

[Brief description of drawings]

FIG. 1 G of digital moving image data according to the present invention
It is a figure which shows the data array in OP, and the whole data array containing audio data.

FIG. 2 is a diagram showing an arrangement of digital moving image video data recorded on the optical disc according to the first embodiment of the present invention.

FIG. 3 is a block circuit diagram of a digital moving picture image information recording apparatus using the optical disc of the first embodiment.

FIG. 4 is a diagram showing a data array of screen division I-picture data in a GOP according to the first embodiment.

FIG. 5 is a flowchart of the first embodiment.

FIG. 6 is a frequency division I in the GOP according to the second embodiment of the present invention.
FIG. 3 is a diagram showing a picture data array and a track jump path during reproduction.

FIG. 7 is a diagram showing a frequency-division I-picture data data array in a GOP of another configuration example of the second embodiment and a track jump path during reproduction.

FIG. 8 is a diagram showing a frequency division I-picture data array in a GOP and a track jump path during reproduction according to another configuration example of the second embodiment.

FIG. 9 is a diagram showing a frequency-division I-picture data array in a GOP and a track jump path during reproduction according to another configuration example of the second embodiment.

FIG. 10 is a flowchart of a second embodiment.

FIG. 11 is a diagram showing a data array on a zone CAV type optical disc of Example 2 when the sample servo type preformat is performed.

FIG. 12 is a diagram showing a data array on a continuous groove type optical disc according to a second embodiment.

FIG. 13 is a block circuit diagram showing an example of a video data restoration circuit from hierarchical data according to a third embodiment of the present invention.

FIG. 14 is a block diagram of a digital moving image / video information reproducing circuit according to a third embodiment.

FIG. 15 is a diagram showing an array of I-picture and P-picture data layered by the number of pixels and the number of lines on the optical disc of the third embodiment.

FIG. 16 is a diagram showing an array of data in which only I-picture data on the optical disc of the third embodiment is layered.

FIG. 17 is a block circuit diagram of a conventional optical disc recording / reproducing apparatus.

FIG. 18 is a diagram showing a data array of the MPEG system.

[Fig. 19] Fig. 19 is a diagram illustrating an encoding structure when 17 screens are 1 GOP.

[Fig. 20] Fig. 20 is a diagram illustrating an encoding structure when 10 screens are 1 GOP.

[Fig. 21] Fig. 21 is a diagram illustrating an encoding structure when 15 screens are 1 GOP.

FIG. 22 is a flow chart in the case of performing special reproduction based on an address in which a scene head portion of digital moving picture image information stored in the recording format of the conventional example is stored in the TOC area of the innermost circumference of the disc.

[Explanation of symbols]

21 GOPs, 22 GOP layers, 23 slices,
24 slice layers, 25 macroblock layers,
26 block layers, 27 I-pictures, 28 B-
Picture, 29 P-picture, 30 header, 31
GOP address, 32 attribute data, 33 audio header, 34 audio data, 35 video header,
36 video data, 37 P-picture header, 38
B-picture header, 39 wall pit / mirror surface part, 40 zone address, 41 sector address, 42
Video GOP address, 43 video attribute data, 4
5 I-picture header, 46 I-picture data 47
I-picture ECC, 48 P-picture header, 49
P-picture data, 50 scalability modes, 51 frames, 52 GOP structure, 53 I
-Data array / position in picture, 54 detailed attribute data, 55 time code, 56 jump destination address,
57 audio mode, 58 still image mode, 59 spare area, 60, 62, 64 I-picture division data, 6
1, 63, 69 I-picture sub-header, 65 P1-
Picture data, 66 P2-picture data, 67
P2-picture data, 68 header, 71-77 frequency division I-picture, 78 P3-picture data, 7
9 P4-picture data, 80 I-picture header,
81 P3-picture header, 82 P4-picture header, 83 A / D converter, 84 motion detector, 85 discrete cosine transformer, 86 adaptive quantizer, 87 inverse quantizer, 88 inverse discrete cosine transformer, 89 Frame memory, 90 variable length encoder, 91 buffer memory, 9
2 format encoder, 93 modulation circuit, 94
Laser modulator, 95 servo circuit, 96 system controller, 97 optical disk, 98 optical head, 99
Feed motor, 100 disk motor, 101 variable length encoder, 102 inverse quantizer, 103 inverse discrete cosine converter, 104 motion compensator, 105 frame memory, 106 decoder, 108 data detection / PLL circuit, 109 header detection / Data classification circuit, 110 error correction circuit, 111 I-picture lower layer data, 112
I-picture upper layer data, 113,120 I-picture sub-header, 114 P1-picture lower layer data, 115 P1-picture upper layer data, 116,1
21 P1-picture sub-header, 117 P2-picture lower layer data, 118 P2-picture upper layer data, 119,122 P2-picture sub-header, 12
3 header and servo pit, 124 sector address, 125 audio data, 126 I-picture sub-header, 127 I-picture data, 128 audio header, 129 specular part, 130 resync byte.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication H04N 5/93

Claims (9)

[Claims] 1. Digital video information is DC in a frame
I-picture data, which is video information for T, and P, which is video information by DCT encoding for motion compensation in the forward direction.
-Several to several tens of frames in which picture data and B-picture data that is DCT-encoded with motion compensation using the above-mentioned I-picture data and P-picture data located temporally before and after as a reference screen are mixed Consecutive video information blocks of a unit, divided into divided I-picture data for each area obtained by dividing the I-picture data on the video screen, and arranging the divided I-picture data in the video information block. An optical disc in which a header signal or a parity signal is recorded before picture data. 2. The DCT-encoded I-picture data is divided into a plurality of sub-blocks divided from data close to direct current of horizontal and vertical frequencies of a video screen to high frequency data, and is divided into a plurality of sub blocks. I-picture, P-picture, and B-of adjacent video information blocks
An optical disc in which sub-blocks of picture data are arranged in a reversed order, and a header or a parity signal indicating, in front of each sub-block, the frequency component of the data of the sub-block is recorded. 3. The DCT-encoded I-picture data is divided into a plurality of sub-blocks divided from data close to direct current of horizontal and vertical frequencies of a video screen to high-frequency data, and is divided into adjacent sub-blocks. The frequency division I-picture data in adjacent video information blocks are arranged so that the arrangements of the frequency division I-picture data are different from each other, and a header indicating which frequency component data the content of the subblock is before the subblock or The optical disc according to claim 2, wherein a parity signal is recorded. 4. Digital video information is DC in a frame
A reference screen for an I-picture that is video information for performing T, a P-picture that is video information for DCT encoding for motion compensation in the forward direction, and the above-mentioned I-picture and P-picture located temporally before and after Motion compensated DC as
A series of video information blocks in a unit of several to several tens of frames in which B-pictures to be T-coded are mixed, and the digital moving picture video information is composed of lower layer data in which both the number of pixels and the number of lines are small, and the lower layer data. It is divided into upper layer data that can be combined with layer data to obtain an image with a large number of pixels and lines, and a header or parity signal for recognizing the type of the data block is recorded before each data block. Optical disc. 5. An I-picture, P-in a video information block
The optical disc according to any one of claims 1, 2, and 4, wherein the order of data arrangement of pictures and B-pictures is different between adjacent video information blocks. 6. A discrimination signal indicating whether the I-picture data is screen division data, frequency division data, or division by the number of pixels and the number of lines is written at the beginning of each video information block. The optical disc according to any one of claims 1, 2, and 4, wherein: 7. The optical disc according to claim 1, wherein the head position of each digital video information block is aligned and recorded in the radial direction of the optical disc. 8. An optical disk reproducing apparatus equipped with a tracking actuator for tracking a scanning spot on a predetermined track, a tracking control circuit, and a track jump circuit for performing interlaced scanning, and performs high-speed special reproduction and reverse reproduction. 5. When performing, the jump operation is repeated based on the header signal or the parity signal recorded before each I-picture to perform high-speed fast-forward reproduction and reverse reproduction. A method for reproducing an optical disc according to any one of 1. 9. An optical disk reproducing apparatus equipped with a tracking actuator for tracking a scanning spot on a predetermined track, a tracking control circuit, and a track jump circuit for performing interlaced scanning, for high-speed special reproduction and reverse reproduction. 7. The method for reproducing an optical disk according to claim 6, wherein when performing the reproduction, the track jump operation is repeated based on the discrimination signal written at the head of each video information block to perform high speed fast forward reproduction and reverse reproduction. .