JPH10271433A - Optical disk recording method and reproducing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow an existing device having provision for interlace video signals to have provision for a progressive video signals without applying a large scale revision to the existing device. SOLUTION: For example, a progressive video signal whose frame rate is 60 frames/sec is given to an input terminal 1, a division means 2 divides the progressive video signal by each frame to convert the progressive video signal into two progressive video signals whose frame rate is 30 frames/sec. The respective progressive video signals are respectively given to compression coding means 3, 4, where the progressive video signal is compression-coded and bit streams are obtained. The two bit streams are given to recording means 5, 6, by which the beams are recorded on different recording layers of an optical disk 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk recording method and a reproducing method for recording or reproducing a progressive video signal on an optical disk having a plurality of recording layers.

[0002]

2. Description of the Related Art In recent years, with the demand for higher image quality, devices for handling video signals having more vertical scanning lines than conventional video signals are increasing. Among them, a progressive scanning video signal called a progressive video signal has attracted attention in relation to digital TV broadcasting. For example, the progressive video signal has a frame rate of 60 (or 5).
9.94) 525 lines per frame at 525 frames per second (525p) or a frame rate of 50
There are 625 lines per frame at 625 lines per second (hereinafter referred to as 625p), and 750 lines per frame at a frame rate of 60 (or 59.94) per second (hereinafter referred to as 750p).

On the other hand, in the field of optical disc devices,
2. Description of the Related Art High-density recording optical disks called digital video disks (hereinafter referred to as DVDs) have been put to practical use. This D
In the VD, a video signal of the NTSC system or the PAL system is compression-encoded by the MPEG system and recorded.

[0004]

When recording or reproducing a progressive video signal on an optical disk such as a DVD, for example, when compressing and coding a 525p progressive video signal, the original number of pixels is 2 bits in the NTSC system. And the rate of the resulting bit stream is also higher. Therefore, there is a case where it cannot be handled within the standard of the existing optical disc. In addition, when decoding (reproducing) an optical disk on which a progressive video signal is recorded in one stream, there is a problem from the user's convenience such that devices already on the market cannot be used.

An object of the present invention is to solve the above-mentioned problems and to provide an optical disk recording method and a reproduction method capable of responding to a progressive video signal at an early stage without making significant changes to conventional equipment. And

[0006]

In order to solve the above-mentioned problems, the present invention divides an input progressive video signal into two progressive video signals lower than the original frame rate, and compresses and encodes each of the two progressive video signals. One bit stream is obtained, and this bit stream is recorded on different recording layers of the optical disc.

[0007] Thus, since the divided progressive video signal can use the same compression encoding means as the conventional video signal, an optical disk recording method and a reproducing method capable of coping with the progressive video signal with a simple configuration can be obtained. Can be

[0008]

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a frame rate N (N
Is the number of frames per second (positive real number), and divides the progressive video signal into two progressive video signals having a frame rate of less than N on a frame basis, and compression-codes the two divided progressive signals, respectively. Obtaining two bit streams and recording the two bit streams on different recording layers of an optical disc, thereby compressing and encoding a video signal having the same rate as an interlace video signal having a frame rate less than N. It can be handled later.

Further, according to the present invention, two bit streams are reproduced from different recording layers of an optical disc, and the respective bit streams are decompressed and decoded to obtain a frame rate N.
Less than (N is the number of frames per second, a positive real number) 2
Two progressive video signals are obtained, the two progressive video signals are combined in frame units, and a progressive video signal having a frame rate N is output, whereby the same as an interlaced video signal having a frame rate less than N is obtained. The video signal of the rate can be handled by the expansion decoding means.

An embodiment of the present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 1 is a block diagram showing an optical disk recording method according to Embodiment 1 of the present invention.

In FIG. 1, 1 is a frame rate N (N
Is an integer greater than or equal to 2). An input terminal to which a progressive video signal is input. 2 is a dividing unit that divides each frame into two progressive video signals, and 3 and 4 are the divided progressive video signals having a frame rate of N / 2. The compression encoding means 5 and 6 for performing compression encoding are recording means for recording the bit stream output from the compression encoding means 3 and 5 on the optical disk 7. The optical disk 7 has at least two recording layers, and records the bit streams from the recording means 5 and 6 on different recording layers.

The operation of the embodiment will be described below.
First, the frame rate of the progressive video signal from the input terminal 1 is set to 60 frames / sec. This progressive video signal is divided by the dividing means 2 into two progressive video signals having a frame rate of 30 frames / sec. As a method of dividing into two, it is desirable to divide by frame alternation.

The divided progressive video signals of 30 frames / sec are respectively input to the compression encoding means 3 and 4, and compression encoded by a method such as MPEG. If the progressive video signal from the input terminal 1 is 525p,
As the compression encoding units 3 and 4, a compression encoding unit for an NTSC video signal can be used. This is because compression of an ordinary interlace video signal is performed by framing two fields into one frame. Also,
Progressive video compression can achieve higher compression efficiency than compression of an interlaced video signal, and therefore can be compressed without any problem. Furthermore, in compression that performs motion compensation such as MPEG, it is not necessary to frame two fields having different time axes, such as an interlace video signal, so that it can be performed with high accuracy.

As a method of dividing the progressive video signal into two signals, it is conceivable to divide each line into two interlaced video signals. It is desirable to divide into two progressive video signals.

The signals compression-encoded by the compression-encoding means 3 and 4 are respectively recorded as bit streams by the recording means 5 and 5.
6 is input. The recording means 5 and 6 are means for recording a signal on an optical disk, and are composed of optical system components such as a semiconductor laser and a lens, but are well known and will not be described in detail.

The recording means 5 and 6 record a bit stream on the recording layer of the optical disk 7, respectively.
One bit stream is recorded on different recording layers.

As described above, according to the present embodiment, the conventional compression coding means for interlaced video signals can be used as it is, and since the compression is performed as a progressive signal, the coding efficiency is reduced by the division. There is no effect.

In this embodiment, the frame rate is set to 60 frames / sec. However, another frame rate such as 59.94 frames / sec or 50 frames / sec (625p) may be used. Here, needless to say,
When a progressive video signal of 50 frames / sec is divided into two, a compression encoding means for a PAL video signal can be used. That is, if an encoder conforming to the MPEG standard is assumed, there is no problem at all.

The optical disk 7 in the present embodiment is
It suffices if two signals can be recorded on two different recording layers,
Recording may be performed on two layers from one side, or may be performed on each recording layer from both sides. The recording time on such an optical disc is the same as when recording an NTSC video signal in one layer.

Further, in the present embodiment, the case of recording on two layers of the optical disk has been described, but the case of recording with two recording means 5 and 6 has been described. You can also record to.

(Embodiment 2) FIG. 2 is a block diagram showing an optical disk reproducing method according to Embodiment 2 of the present invention. In FIG. 2, reference numeral 7 denotes an optical disk on which signals are recorded by the method of the first embodiment. 8, 9
Reproducing means for reproducing bit streams from different recording layers of the optical disc 7, respectively, 10 and 11 decompress and decode bit streams from the reproducing means 8 and 9, and 12 decompress and decode. A synthesizing means for synthesizing the progressive video signal of the frame rate N / 2 from the means 10 and 11 into a progressive video signal of the frame rate N, and 13 is an output terminal for outputting the progressive video signal from the synthesizing means 12.

The present embodiment is a reverse process of the first embodiment and does not require any particular explanation.

[0023] Decompression decoding means 10, 1 according to the present embodiment.
1 outputs a progressive video signal having a frame rate of N / 2. Therefore, the compression encoding means 3, 3 shown in FIG.
Similarly to 4, the decompression decoding means 10 and 11 can make the frame rate N / 2 equivalent to that for the interlace video signal.

Then, a progressive video signal having a frame rate N can be obtained by the synthesizing means 12 which is the reverse of the division order at the time of recording. At this time, it goes without saying that a method of putting some kind of synchronization information into the bit stream is adopted so that the order of synthesis is the same as that at the time of division.

As described above, according to the present embodiment, the conventional decompression decoding means for interlaced video signals can be used as it is, so that a device for progressive video signals can be obtained early.

In this embodiment, the case where the reproduction is performed from the two layers of the optical disk has been described by the two reproduction means 8 and 9, but the one reproduction means performs the time division control on the two layers. You can also play from.

(Embodiment 3) FIG. 3 shows Embodiment 3 of the present invention.
1 is a block diagram showing a configuration of an optical disk reproducing method according to the present invention. The present embodiment shown in FIG. 3 is different from FIG. 2 in the second embodiment in that only one bit stream is reproduced and the synthesizing means 12 is omitted. Therefore, the output from the output terminal 14 is output at the frame rate N / 2 (for example,
(For example, 30 frames / second).

The present embodiment corresponds to a device that has been on the market in advance. Therefore, it is possible to easily reproduce the optical disk 7 created by using the recording method according to the first embodiment.

(Embodiment 4) FIG. 4 shows Embodiment 4 of the present invention.
1 is a block diagram showing a configuration of an optical disk reproducing method according to the present invention. The present embodiment shown in FIG. 4 is different from FIG. 3 in the third embodiment in that a field division unit 15 is provided at a stage subsequent to the decompression decoding unit 10.

The field dividing means 15 converts the progressive video signal of the frame rate N / 2 output from the decompression decoding means 10 into an interlace video signal and outputs it from an output terminal 16. Therefore, the output of the field dividing means 15 is an interlace video signal having a frame rate of N / 2 (a video signal of the NTSC system if N = 60).
become. Therefore, it can be viewed on the ordinary monitor TV from the output terminal 16.

As described above, according to the present embodiment, only one of the 1 / 2-rate progressive video signals divided and recorded in different layers is reproduced, decompressed and decoded, and then converted to an interlaced video signal. Therefore, the optical disk 7 created by using the recording method according to the first embodiment can be easily reproduced.

The field division method may be such that a delay of 0 second or 1 / N second is given to every other horizontal line and output, or a spatial or temporal filtering process is performed and output. Is also good.

(Embodiment 5) FIG. 5 shows Embodiment 5 of the present invention.
1 is a block diagram showing a configuration of an optical disk reproducing method according to the present invention. The present embodiment shown in FIG. 5 is different from FIG. 3 in the third embodiment in that a frame interpolation unit 17 is provided at a stage subsequent to the decompression decoding unit 10.

The frame interpolation means 17 converts the progressive video signal of the frame rate N / 2 output from the decompression encoding means 10 into a progressive video signal of the frame rate N and outputs it from the output terminal 18. As a method of frame interpolation, for example, one frame may be output twice. FIG. 6 shows this state.

In FIG. 6, since the output of the decompression decoding means 10 has a frame rate N / 2 as shown in FIG. 6A, if one frame is output twice at the frame rate N, the output of FIG. It becomes like b).

As a method for obtaining a progressive video signal having a frame rate N as shown in FIG. 6B, a frame to be interpolated can be obtained by filtering using the preceding and succeeding frames. In this case, a method of simply adding pixels at the same position in the preceding and succeeding frames and halving the sum, or a method of detecting the correlation (or motion) of the preceding and succeeding frames and adaptively changing the filtering process may be employed. good.

Further, a progressive video signal having a frame rate of N / 2 may be converted into a progressive video signal having a frame rate other than N and output. For example, FIG. 6C shows an interpolation (pull-down) method when converting to a frame rate of 1.2 × N. In FIG. 6C, FIG.
Each frame of the video signal of the frame rate N / 2 in (a) is repeatedly output, for example, three times, two times, three times, two times, and two times, thereby obtaining 2.4 times the original frame rate. I have to. That is, the frame rate N / 2 is converted to the frame rate 1.2 × N.

By doing so, for example, the frame rate N
Is 60 frames / sec, the output is 72 frames / sec, and it can be output to a display such as a personal computer with a high frame rate. If the frame rate N is 5
If 0 frames / sec, the output will be 60 frames / sec,
The frame rate can be converted.

As described above, according to the present embodiment, only one of the 1/2 rate progressive video signals divided and recorded on different layers is reproduced, expanded and decoded, and then doubled or doubled. Since the video signal is converted into a progressive video signal having a .times.4 frame rate and output, the first embodiment is used.
The optical disk 7 created by using the recording method according to the above can be simply reproduced as a progressive video signal.

In the above embodiment, the division of the progressive video signal of the frame rate N is divided into two parts by the frame alternation to obtain the progressive video signal of the frame rate N / 2. If it is less than N, any other than equal division may be used. For example, 5
A progressive video signal of 0 frames / sec may be divided into two frames of 30 frames / sec and 20 frames / sec in frame units, or may be periodically (for example, once every 5 frames) to both systems. A progressive video signal of 50 frames / sec may be divided into two frames of 30 frames / sec by providing a frame to which the frame belongs, and in short, the frame rate may be lower than the original frame rate.

The two bit streams obtained by compression-encoding the divided progressive video signals preferably have the same bit rate in terms of recording time, but this includes information other than the video signals. That is, the divided 2
If the progressive video signals have different frame rates (or compression-encoded bit rates),
It is preferable that the two recording layers can be effectively used by adding additional information such as a header or audio information to only one bit stream.

[0042]

As described above, according to the present invention, a progressive video signal having a frame rate N is divided to obtain a progressive video signal having a frame rate less than N, and compression-encoded bit streams are respectively recorded on the optical disk by different recording methods. Since recording is performed in the layers, the encoding and compression means can be the same as that for an interlace video signal having a frame rate of less than N. When an optical disk recorded by this method is reproduced, the expansion and decoding means can be the same as that for an interlace video signal having a frame rate less than N. Further, only one layer is reproduced from the optical disc to realize a progressive video signal having a frame rate of N / 2, N, 1.2 × N or an interlace video signal having a frame rate of N / 2 with a simple circuit addition. be able to.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an optical disc recording method according to a first embodiment of the present invention;

FIG. 2 is a block diagram showing a configuration of an optical disc reproducing method according to the second embodiment;

FIG. 3 is a block diagram showing a configuration of an optical disc reproducing method according to the third embodiment;

FIG. 4 is a block diagram showing a configuration of an optical disk reproducing method according to the fourth embodiment;

FIG. 5 is a block diagram showing a configuration of an optical disc reproducing method according to the fifth embodiment;

FIG. 6 is a conceptual diagram showing an operation of frame interpolation in the optical disc reproducing method.

[Explanation of symbols]

 2 Dividing means 3, 4 Compression encoding means 5, 6 Recording means 7 Optical disk 8, 9 Reproducing means 10, 11 Decompression decoding means 12 Combining means 15 Field dividing means 17 Frame interpolation means

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toyohiko Matsuda 1006 Kadoma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd.

Claims (13)

[Claims] 1. A progressive video signal having a frame rate N (where N is a number of frames per second and a positive real number) is divided into two progressive video signals having a frame rate less than N on a frame-by-frame basis. An optical disc recording method for compressing and encoding two progressive signals to obtain two bit streams and recording the two bit streams on different recording layers of the optical disc. 2. The optical disk recording method according to claim 1, wherein the progressive video signal having a frame rate N is divided into two progressive video signals having a frame rate N / 2 by frame alternation. 3. The optical disk recording method according to claim 1, wherein the two bit streams are recorded on different recording layers from different surfaces of the optical disk. 4. The recording apparatus according to claim 1, wherein the two bit streams are recorded on different recording layers from the same surface of the optical disc.
Or the optical disc recording method according to 2. 5. The frame rate N is 60 frames /
5. The optical disc recording method according to claim 1, wherein the recording speed is set to 59.94 frames / second or 50 frames / second. 6. The optical disk recording method according to claim 2, wherein the two bit streams have the same bit rate. 7. Reproducing two bit streams from different recording layers of the optical disc, and decompressing and decoding each bit stream to obtain a frame rate less than N (N is 1
An optical disc reproducing method for obtaining two progressive video signals (positive real number in frames per second), synthesizing the two progressive video signals in frame units, and outputting a progressive video signal of a frame rate N. 8. A progressive video signal having a frame rate N (N is the number of frames per second, which is a positive real number) divided into two progressive video signals having a frame rate of less than N as a bit stream which is compression-coded. A method for reproducing an optical disc recorded on a different recording layer, wherein only one recording layer is reproduced to obtain a bit stream, and the bit stream is decompressed and decoded to form a progressive video signal having a frame rate less than N. An optical disk playback method to output. 9. The optical disk reproducing method according to claim 8, wherein a progressive video signal having a frame rate of less than N is divided into fields and output as an interlaced video signal having a frame rate of less than N. 10. The optical disk reproducing method according to claim 8, wherein a progressive video signal having a frame rate lower than N is frame-interpolated and output as a progressive video signal having a frame rate N. 11. A progressive video signal having a frame rate less than N is pulled down to a frame rate of 1.2 ×
9. The optical disk reproducing method according to claim 8, wherein the method is output as N progressive video signals. 12. The frame rate N is 60 frames /
12. The optical disk reproducing method according to claim 7, wherein the reproduction time is set to 59.94 frames / second or 50 frames / second. 13. The optical disk reproducing method according to claim 7, wherein the progressive video signal having a frame rate less than N is a progressive video signal having a frame rate of N / 2.