JPH10336585A - Dynamic image recording/reproducing device and dynamic image recording/reproducing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dynamic image recording device that employs one kind of optical disk and one device to record a video signal of two kinds of standard, TV and HDTV systems. SOLUTION: A standard TV video signal from an input terminal 101 or an HDTV video signal from an input terminal 102 is selected by an input video image changeover section 105 and given to a video coding section 106, and a GOP length N1 when the standard TV video signal is received and a GOP length N2 when the HDTV video signal is received depending on the recording mode set by a recording mode setting section 113 are related as N1<N2 for compression coding. Obtained coded data are given sequentially to an error correction coding section 110 and a modulation section 111 via a stream changeover section 109, and identical error correction coding processing and modulation processing are conducted on the input of the standard TV video signal and the input of the HDTV video signal, and an optical disk recording section 112 is used to conduct recording on an optical disk.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving picture recording / reproducing apparatus and a moving picture recording / reproducing method for recording / reproducing a moving picture signal using a recording medium such as an optical disk which can be rewritten by a compression encoding technique.

[0002]

2. Description of the Related Art Moving picture coding techniques for transmitting and storing a large amount of video signals with a smaller data amount include, for example, MP
Practical use is progressing as represented by the EG2 video standard (ISO / IEC13818-2). In the MPEG2 video standard (hereinafter, simply referred to as MPEG2), one screen of a moving image signal is divided into a plurality of blocks each having a size of 8 × 8 pixels, and each block is subjected to DCT (discrete cosine transform). , Is based on quantizing the obtained DCT coefficient data and performing variable length coding. Also,
By using the motion compensation inter-picture prediction together, the coding efficiency is enhanced by utilizing the correlation of the images in the time direction.

[0003] By applying such moving picture coding technology, MP
A digital video disk (DV) in which a moving image signal compressed by EG2 is prerecorded on a read-only optical disk.
D) and its playback device are also currently being commercialized. Digital video discs cannot be rewritten by users because they are read-only, but large-capacity rewritable optical discs are currently being developed. Even when such a rewritable optical disk is used for recording / reproducing digital video data, in order to lengthen the recording time,
For example, it is conceivable that the information amount is compressed and recorded by moving image encoding such as MPEG2.

On the other hand, standard TVs represented by the NTSC system
The HDTV (high-definition television) system, which has five times or more the amount of original information as the system, has reached a practical period. But,
Even if the information amount of the video signal is compressed by a moving picture encoding technique such as MPEG2, the information amount after compression is still larger in the HDTV video signal than in the standard TV video signal. If you perform recording and playback using
The recording time of the DTV video signal is shorter.

Therefore, if the same recording time is to be obtained for both HDTV video signals and standard TV video signals, the format of the rewritable optical disc is as follows.
Two types of optical disks having different recording rates and recording capacities are required. That is, for a standard TV, an optical disc with a low recording rate and a small recording capacity is used,
For V, optical disks with high recording rates and large recording capacities are required.

If an optical disc having a low recording rate and a small recording capacity for a standard TV is to be used for an HDTV, the recording rate is insufficient and the image quality is greatly reduced, and the recording time is short because the recording capacity is insufficient. Become. vice versa,
If an optical disc having a high recording rate and a large recording capacity for HDTV is to be used for a standard TV, a large waste of recording capacity occurs and the recording efficiency is reduced. Thus, at present, there is no format suitable for recording two types of video data, a standard TV video signal and an HDTV video signal, on one type of rewritable optical disc.

[0007] Further, if an attempt is made to supply a recording / reproducing apparatus corresponding to two kinds of video signals of a standard TV and an HDTV,
Since there are two types of optical discs, two types of devices are required. That is, the user has to purchase two types of recording / reproducing devices for standard TV and HDTV. Furthermore, if one unit can handle two types of rewritable optical disks having different recording rates and recording capacities, the cost of the apparatus increases, and the weight and power consumption also increase.

[0008]

As described above, the conventional technique has a problem that there is no format suitable for recording two kinds of video signals of the standard TV system and the HDTV system on one kind of rewritable optical disk. There is no moving image recording device / reproducing device capable of recording / reproducing these two types of video signals by one unit, and two types of rewritable optical disks differing in recording rate and recording capacity by one However, there is a problem that the cost of the apparatus is increased, and the weight and power consumption are increased.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and uses one type of recording medium, and can use one apparatus to convert two types of video signals of a standard TV system and an HDTV system into image quality deterioration and the like. An object of the present invention is to provide a moving image recording / reproducing apparatus and a moving image recording / reproducing method capable of recording / reproducing without lowering recording efficiency.

[0010]

In order to solve the above-mentioned problems, a moving picture recording apparatus according to the present invention comprises a coding means for compressing and coding an input moving picture signal in an independently decodable unit having an arbitrary number of screens. A moving picture signal of a first television system having a first effective pixel rate and a second television system having a second effective pixel rate higher than the first effective pixel rate. Means for selectively inputting any one of the moving image signals of the first television system and the encoding unit comprises: N1 and 2nd
The relationship between the number of screens N2 included in the independently decodable unit when the video signal of the television system is input is represented by N1 <N.
2 is characterized by performing compression encoding.

Another moving picture recording apparatus according to the present invention has an image pickup means for picking up a moving picture and outputting a moving picture signal, and a moving picture signal outputted from the picking up means having a first effective pixel rate. The moving image signal of the first television system and the first
Conversion means for converting the video signal into one of the video signals of the second television system having a second effective pixel rate higher than that of the television system and inputting the video signal to the encoding means, The number N1 of screens included in the independently decodable unit when the video signal of the first television system is input and the number of screens N1 included in the independently decodable unit when the video signal of the second television system is input The compression encoding is performed by setting the relationship of the number of screens N2 to be N1 <N2.

Here, the independent decodable unit is, for example, M
This is a GOP (Group of Pictures) in PEG2, and the number of pictures (the number of screens) included in the GOP is called a GOP length.

As described above, the number of screens N1, N included in the independently decodable unit at the time of recording the moving image signal of the first television system and the time of recording the moving image signal of the second television system.
If the relationship of 2 is selected, the difference between the generated code amount of the first television system and the generated code amount of the second television system can be eliminated or reduced.

That is, in the independently decodable unit, there are generally a fixed number (usually one) of screens, so-called I pictures, which are intra-coded so as to be completed within one screen. This I picture has a much larger generated code amount than other picture types such as a P picture and a B picture. Therefore, if the GOP length, which is an independently decodable unit, is shortened, the frequency of I pictures increases and the amount of generated codes increases, and if the GOP length is increased, the frequency of I pictures decreases and the generated code amount decreases. .

As a result, in the first television system having a small amount of information, the GOP length is shortened to increase the generated code amount, and in the second television system having a large amount of information,
By increasing the P length and reducing the generated code amount, the generated code amount in both systems approaches, and the GOP length and GO
By appropriately setting the configuration of P, the amount of generated codes can be made substantially equal. Therefore, it is possible to record both the video signal of the first television system and the video signal of the second television system on one type of recording medium without shortage of recording time and waste of recording capacity.

Further, the moving picture recording apparatus according to the present invention can be adapted to a case where a moving picture signal of the first television system is inputted and a case where a moving picture signal of the second television system is inputted to the encoding means. The compression encoding is performed so that the average encoding rate or the maximum encoding rate becomes substantially the same, and further, the video signal of the first television system is supplied to the encoding unit for the signal recorded on the recording medium. It is characterized by further comprising processing means for performing the same error correction coding processing and modulation processing when the video signal is input and when the video signal of the second television system is input. By doing so, the recording of the video signal of the first television system and the video signal of the second television system can be performed by using a recording device that is almost common with one type of recording medium.

More specifically, the first television system is, for example, a standard TV system having 720 horizontal pixels and 480 or 486 vertical luminance signal effective pixels per frame, and a second television system. The television system is, for example, an HDTV system having 1920 pixels in the horizontal direction and 1035 pixels or 1080 pixels in the vertical direction for each frame. In this case, the encoding means is N
It is desirable that 1 be N1 = 1 or N1 = 2 and N2 be N2 = 15. The average coding rate is 14M
It is desirable to be set to not less than bps and not more than 28 Mbps.

Further, the present invention provides a method for identifying whether a moving picture signal input to an encoding means is a moving picture signal of a first television system or a moving picture signal of a second television system. The flag is recorded on a recording medium. By recording such a flag in association with the encoded data of a moving image signal on a recording medium, the recorded data can be reproduced in any one of the first television mode and the second television mode during reproduction. It is possible to automatically identify whether or not to play.

A moving picture reproducing apparatus according to the present invention has a moving picture signal of a first television system having a first effective pixel rate and a second effective pixel rate higher than the first effective pixel rate. A moving image reproducing apparatus for reproducing a moving image signal from a recording medium in which one of the moving image signals of the second television system is compression-encoded and recorded, wherein the first moving image signal is recorded on the recording medium from the recording medium. Detecting means for detecting whether a moving image signal of the television system is recorded or a moving image signal of the second television system is recorded; When the video signal of the first television system is recorded on the recording medium, the number of screens N1 included in the independently decodable unit and the video signal of the second television system are recorded. Independently decodable units relationship screen number N2 contained in the case, characterized by comprising a decoding means for performing decoding as N1 <N2.

Further, the moving picture reproducing apparatus according to the present invention comprises:
Regarding the signal reproduced from the recording medium, the case where the moving image signal of the first television system is recorded on the recording medium and the case where the moving image signal of the second television system are recorded are the same. A demodulation process and an error correction decoding process.

With such a configuration, reproduction of both the first television system and the second television system is performed from the recording medium on which recording has been performed as described above using a substantially common reproducing apparatus. Can be.

Further, according to the present invention, a video signal of a first television system having a first effective pixel rate and a second video signal having a second effective pixel rate higher than the first effective pixel rate. When one of the video signals of the television system is selectively inputted and the video signal of the first television system is inputted, the number N1 of screens included in the independently decodable unit and the second television Of screens included in the independently decodable unit when a moving image signal of the N scheme is input
, N1 <N2, and the average coding rate or the maximum coding rate when the moving image signal of the first television system is input and when the moving image signal of the second television system is input. Are compressed and encoded so as to be substantially the same, and a moving image signal of the first television system and a moving image signal of the second television system are input to the moving image signal after the compression encoding. When an image signal is input, the same error correction encoding processing and modulation processing are performed, and the moving image signal of the error correction encoding processing and modulation processing is a moving image signal of the first television system or a second moving image signal. A moving image recording method for recording on a recording medium together with a flag for identifying whether the moving image signal is a television system moving image signal.

Further, according to the present invention, a video signal of a first television system having a first effective pixel rate and a second video signal having a second effective pixel rate higher than the first effective pixel rate. A moving image reproducing method for reproducing a moving image signal from a recording medium in which one of the moving image signals of the television system is selectively compression-encoded and recorded. , The first on the recording medium
The same demodulation processing and error correction decoding processing as when the moving image signal of the television system is recorded and when the moving image signal of the second television system is recorded are performed. A flag for identifying whether a moving image signal of the first television system or a moving image signal of the second television system is recorded on the recording medium, and a detection result of the flag is detected. When the video signal of the first television system is recorded on the recording medium, the number N1 of screens included in the independently decodable unit and the video signal of the second television system are recorded in accordance with. Number of screens included in the independently decodable unit when
A moving image reproduction method is characterized in that decoding is performed with the relationship of N2 <N2 <N2.

Further, according to the present invention, there is provided a recording medium on which a moving image signal is compression-encoded and recorded, wherein the recorded moving image signal has a first effective pixel rate. Recording medium for recording a flag for identifying whether the moving image signal is a moving image signal of the second television system having a second effective pixel rate higher than the first effective pixel rate. Is provided.

[0025]

Embodiments of the present invention will be described below with reference to the drawings. In the following embodiments, a case will be described in which a rewritable optical disk is used as a recording medium, and recording and reproduction of compression-encoded moving image data and audio data are performed.

(First Embodiment) First, a first embodiment of the present invention will be described with reference to FIGS. FIG.
FIG. 1 shows a schematic configuration of a moving image recording apparatus according to a first embodiment of the present invention. This moving image recording apparatus has a standard TV video input terminal 101 and an HDTV video input terminal 10 as input terminals.
2. It has a compressed data input terminal 103 and an audio input terminal 104, an input video switching unit 105, a video encoding unit 10
6, audio encoding unit 107, system multiplexing unit 10
8, stream switching section 109, error correction encoding section 1
10, a modulation unit 111, an optical disk recording unit 112, and a recording mode setting unit 113.

In this embodiment, the moving image signal to be encoded is either a standard TV video signal input from the standard TV video input terminal 101 or an HDTV video signal input from the HDTV video input terminal 102. Either one is selected by the video switching unit 105 and supplied to the video encoding unit 106. In the video encoding unit 106, the input video signal is subjected to processing such as motion compensation prediction, DCT, quantization, and variable-length encoding based on the MPEG2 system, and is compression-encoded. On the other hand, the audio input terminal 104
The audio signal input from the
Is compressed and encoded.

The encoded data output from the video encoding section 106 and the audio encoding section 107 are multiplexed by the system multiplexing section 108 to form an MPEG2 system stream. In the stream switching unit 109, one of the compressed data from the compressed data input terminal 103 and the MPEG2 system stream from the system multiplexing unit 108 is selected. Stream switching unit 10
9 is subjected to error correction encoding by, for example, a Reed-Solomon product code by an error correction encoding unit 110, and further modulated by a modulation unit 111 according to the characteristics of the recording medium, that is, data. By performing the conversion, recording data is generated.

The recording data from the modulation unit 111 is input to the optical disk recording unit 112. Optical disk recording unit 1
Reference numeral 12 includes an optical pickup, a mechanical unit, a servo control unit, and the like, and performs recording on a rewritable optical disk such as a phase-change optical disk or a magneto-optical disk. The recording mode setting unit 113 sets the mode of each unit based on the recording mode determined as described later.

Next, the operation of the moving picture recording apparatus of this embodiment will be described more specifically. Standard TV video input terminal 10
The standard TV video signal input from 1 has an effective number of luminance pixels per frame of 720 horizontal pixels, 480 lines or 486 lines, and the HDTV video signal input from the HDTV video input terminal 102 has 1 effective pixel. The number of effective pixels of the luminance signal per frame is 1920 horizontal pixels and 1 vertical pixel.
035 lines or 1080 lines. At the time of compression encoding in the video encoding unit 106, the number of effective pixels and the number of lines are rounded up or down to a multiple of 16. The frame frequency of both the standard TV video signal and the HDTV video signal is 30 Hz or 29.
97 Hz, and the color difference signal has half the number of pixels in the horizontal direction as the luminance signal.

The moving image recording apparatus according to the present embodiment has roughly the following three types of recording modes. (1) Standard TV recording mode (2) HDTV recording mode (3) Compressed data recording mode The compressed data recording mode is further divided into a compressed standard TV data recording mode and a compressed HDTV data recording mode depending on the content of the compressed data. Information on these recording modes is stored in the recording mode setting unit 113.

At the standard TV video input terminal 101, HDTV video input terminal 102, and compressed data input terminal 103, the presence or absence of each input signal is detected electrically or logically. Will be displayed accordingly. On the other hand, the user can input information on a desired recording mode from a recording mode input unit (not shown).

From the detection result of the presence or absence of these input signals and the desired recording mode input by the user, the optimum recording mode is automatically selected and displayed. For example,
When only one of the three input signals of the standard TV video signal, HDTV video signal and compressed data is input, the recording mode corresponding to the input is automatically selected. When there are two or more types of inputs, the recording mode is automatically selected in preference to the user's input. If there is no input corresponding to the desired recording mode input by the user, a warning is displayed.

Information on the recording mode determined in this way is supplied from the recording mode setting unit 113 to each unit, and the mode of each unit is set. Specifically, the input video switching unit 105 selects one of the standard TV video signal and the HDTV video signal according to the standard TV recording mode or the HDTV recording mode, and the video encoding unit 106 Is set. Further, in the stream switching unit 109, one of the compressed data from the compressed data input terminal 103 and the MPEG2 system stream from the system multiplexing unit 108 is selected according to the compressed data recording mode or another recording mode. .

A flag indicating the recording mode is recorded on the optical disk. This flag is preferably recorded in the management area on the optical disk, but may be inserted in the MPEG2 system layer or may be recorded outside the MPEG2 system layer. Further, the information may be recorded not only on the optical disk but also in another part such as a semiconductor memory attached to a cartridge of the optical disk.

In the compressed data recording mode,
Whether the input compressed data is standard TV compressed data or not
Whether the data is DTV compressed data is automatically extracted from the input data itself, or is input through another path, and is recorded as a flag indicating the recording mode.

Further, data of a standard TV video signal and data of an HDTV video signal, or other compressed data can be mixedly recorded on the same optical disk. For example, information about area division on the optical disk and a flag for identifying a recording mode corresponding to each of the divided areas may be recorded in a management area on the optical disk.

As described above, the flag indicating the recording mode is recorded at the time of recording, and by reading and detecting this flag at the time of reproduction, it is possible to identify in which mode the processing should be performed at the time of reproduction.

When each of these recording modes is selected automatically or manually, the power supply to unnecessary circuits is cut off or the clock is stopped to reduce the power consumption. Can also. For example, when the compressed data recording mode is selected, the video encoding unit 10
By taking measures such as not supplying power to the system 6 and the system multiplexing unit 108 or stopping the clock, it is possible to reduce the power consumption of these large power consumption parts.

Next, compression encoding in the video encoding unit 106 will be described in detail. In the present embodiment, encoding is performed by switching a GOP (Group of Pictures) length and a GOP configuration according to whether an input video signal is a standard TV video signal or an HDTV video signal. Features.

Here, as is well known, MPE
The GOP in G2 will be briefly described. GO
P is a minimum unit (independently decodable unit) that can be decoded independently of other parts, and is composed of a plurality of temporally continuous pictures or one picture (screen). The head of the GOP serves as an access point, and video can be independently decoded and reproduced from this point. This has important implications for editing and random access. In particular, if a closed GOP is restricted in advance so that motion compensation prediction is not performed between GOPs, the GOP is a unit that can be independently decoded without disturbing the video at all.

At the beginning of a GOP on the coded bit stream, an I (Intra code) for performing complete coding within the screen
d: Intra coding = Intra-frame coding) A picture is arranged. The types of pictures include P (Predictive coded) pictures that perform predictive coding from I or P pictures located in the past in addition to I pictures, and temporally forward / backward / bidirectional pictures. B (Bidirectionally predictive c) that performs predictive coding from an I or P picture
oded: bidirectional prediction coding) There are three types of picture types. In general, the amount of information of an I picture is large, followed by a P picture and a B picture.

In general, one GOP can have a plurality of I pictures, but in this embodiment, one GOP
The description will be made on the assumption that one I picture is included. Although the length and picture configuration can be dynamically changed for each GOP, in the present embodiment, a series of sequences will be described with the GOP length and the picture configuration in the GOP fixed.

In the present invention, attention is paid to the fact that the generated code amount differs for each of the I, P, and B picture types, and that the generated code amount differs between the standard TV video signal and the HDTV video signal. That is, since the amount of generated codes differs for each picture type, it is possible to control the generated codes by changing the length of the GOP and the picture configuration. The GOP length and the picture configuration of the GOP are set so as to increase the code amount, and the HDTV having the originally generated code amount is large.
In a video signal, the GOP length and the picture configuration are set so that the generated code amount is reduced. Thus, almost the same encoding rate can be used for encoding both the standard TV video signal and the HDTV video signal, and a common recording medium (optical disc) and recording / reproducing apparatus can be used.

Next, a more detailed description will be given with reference to specific numerical examples. The GOP length, that is, the number of pictures (the number of screens) included in one GOP is set to N. In this example, 1 GOP
Contains one I picture, N is equal to the period of the I picture. In the following, N = 15, N = 2, N =
An example using three values of N of 1 will be described.

FIGS. 2A, 2B, and 2C show GOP configurations in the input order in each case of N = 15, N = 2, and N = 1 assumed in the present embodiment. That is, FIG.
Is N = 15, 1 GOP is composed of one I picture and 4
It consists of P pictures and 10 B pictures. FIG.
In the case of N = 2 in (b), one GOP is composed of one I picture and one P picture. When N = 1 in FIG. 2C, one GOP includes only one I picture. In the case of N = 2, in addition to the GOP configuration in FIG. 2B, a configuration including a B picture and an I picture in an input order may be employed. However, in this case, if a closed GOP is used, only a backward prediction can be used even if it is a B picture, so that the generated code amount is substantially equivalent to a P picture.

As described above, with regard to the code amount per picture for each picture type, the code amount of the I picture is the largest, then the P picture, and finally the B picture. Therefore, when the GOP length is increased to increase the composition ratio between the B picture and the P picture, the average code amount per picture decreases. As a specific numerical example, when the code amount is distributed so that the image quality of each picture is substantially averaged for the standard TV video signal, the code amount per I picture = 5.5 BP picture Code amount per picture = 2.5B Code amount per picture of B picture = B. Here, B is a certain constant.

FIGS. 3 (a), 3 (b) and 3 (c) show changes in the code amount for each picture type in this GOP.
It is the figure shown corresponding to (b) and (c), respectively. 1
Since the code amount per second is 30 frames (30 pictures) per second, when N = 15, (5.5B + 2.5B × 4 + B × 10) × 2 = 51B When N = 2, (5. 5B + 2.5B) × 15 = 120B In the case of N = 1, 5.5B × 30 = 165B. That is, when trying to encode the same video signal so as to obtain substantially the same image quality, N = 15,
The ratio of the generated code amount in each case of N = 2 and N = 1 is approximately 1: 2.35: 3.24 (= 51: 120: 165).

The effective pixel rate (the number of effective pixels) of the HDTV system is about 5.5 times the effective pixel rate (the number of effective pixels) of the standard TV system. However, in the HDTV system, since the density of pixels is high, the correlation between pixels in the DCT block is high, so that the coding efficiency is improved by that much compared to the standard TV system. That is, in the HDTV system, although the number of pixels is large, the required code amount does not become larger than that in the standard TV system. Considering this, the same G
HDTV so that almost the same SN ratio can be obtained with the OP configuration
The ratio of the code amount when the video signal is coded to the code amount when the standard TV video signal is coded is about 2: 1 to 4: 1.

In the HDTV recording mode, the GOP length N is set to 1
5 (the configuration of FIG. 2A), the amount of generated codes per second can be calculated using the constant
In the case of (N = 15), 51B × (2-4) = 102B-
It is about 204B. That is, the generated code amount when encoding the HDTV video signal of N = 15 is substantially equal to the generated code amount when encoding the standard TV video signal of about N = 1 or 2.

For the reasons described above, in this embodiment, the GOP length N in the standard TV recording mode is set to N1, and
When the GOP length N in the DTV recording mode is N2, the relationship between the two is N1 <N2, and specifically, for example, N1 = 1
Alternatively, by setting N1 = 2 and N2 = 15 and performing coding at substantially the same coding rate, substantially the same SN ratio and subjective image quality (excluding the difference in resolution) can be obtained in any mode. I have to.

In general, when the GOP length is long, there is a problem that the minimum unit that can be edited in a bit stream state becomes long, and that it is difficult to perform reverse reproduction. On the other hand, if the GOP length is short, the editable unit is short, and reverse playback is easy.

That is, in the case of the standard TV recording mode,
Since the GOP length is as short as N = 1 or N1 = 2, it is possible to add a feature that it is possible to perform sophisticated editing and reverse reproduction with high accuracy for business use or high amateur use. On the other hand, in the HDTV recording mode, G
Since the OP length is as long as N2 = 15, it is disadvantageous in terms of editing and reverse reproduction, but it is possible to enjoy a high-resolution beautiful image.

In this embodiment, the video encoding unit 10
6 is performed at a fixed rate.
Here, the fixed rate indicates that the video code amount per GOP is constant. For a specific video coding rate in the case of fixed rate coding, a standard TV video signal having a GOP length of N1 = 1, N1 = 2, or N2 =
14 Mbps to 2 for 15 HDTV video signals
It is empirically desirable to set it to about 8 Mbps. 14M
If it is set to about bps, recording and reproduction for a long time can be performed, and 28 Mb
At about ps, high-quality recording and reproduction can be performed. Such a coding rate is not necessarily limited to one type, and a plurality of modes relating to the coding rate may be set. In this case, of course, mode information on the encoding rate is also recorded on the optical disk.

For example, as shown below, various recording modes according to the intended use can be provided using one type of recording medium, depending on the combination of the GOP length and the video encoding rate.

[0056]

[Table 1]

One of the features of the present invention is that the error correction encoder 110, the modulator 111, and the optical disc recorder 1
12 is common regardless of the recording modes. By making these processes common in each recording mode, the size and power consumption of the recording apparatus can be reduced. Among them, the modulation method is, for example, 8-
A 16 modulation scheme or the like can be used.

Here, the configuration of the error correction code will be specifically described. The basic configuration of the error correction code is a standard TV
The recording mode and the HDTV recording mode are common. In this example, the error correction code is a Reed-Solomon product code,
It has the same code configuration as a normal read-only digital video disk.

FIG. 4 shows the configuration of this error correction code.
M that multiplexes compressed video data and compressed audio data
For the PEG2 system stream, ID / ID is assigned to the minimum unit of 2K bytes (2048 bytes) of data.
2064 bytes are added by adding data called IED, etc., and 16 bytes are collected into 33024 bytes (main data, that is, MPEG2 data is 32768 bytes).
Bytes) is one unit of the error correction block. This unit is arranged in 172 columns × 192 rows. First, an outer code check word of 16 bytes is added vertically for each column, and then an inner code check word of 10 bytes is added horizontally for each row. At the time of actual recording, these are again divided into 16 recording sectors and recorded.

Considering the convenience of error correction processing, MPE
The data of the G2 system layer is 32768 for each GOP.
Preferably, it is an integer multiple of bytes. That is, when recording at a fixed rate, MP per GOP
It is assumed that the data amount of the EG2 system layer is an integral multiple of 32768 bytes. At this time, dummy data is added and 327
It may be an integral multiple of 68 bytes. Desirably, the compressed data from the compressed data input terminal 103 is originally in this form as well, but if there is a data amount mismatch, dummy data is added to make each GOP an integral multiple of 32768 bytes.

For example, in the recording mode where the GOP length (N) is N = 1, if the number of error correction blocks in FIG. 4 per GOP is 2 to 4, the data rate of the MPEG2 system layer is 32768 × ( 2-4) x 3
0 × 8 = 15.7 Mbps to 31.5 Mbps,
The aforementioned video coding rate (14 Mbps to 28 Mbps)
s).

In the description so far, the video encoding unit 10
Although it is assumed that the code amount control in No. 6 is fixed-rate coding, the code amount control may be variable-rate coding. In variable rate coding, the image quality can be kept almost constant by making the amount of allocated bits variable according to the complexity of the image.

In the case of this variable rate coding, the standard TV
The maximum coding rate is made common between the recording mode and the HDTV recording mode, for example, as follows. (1) Standard TV recording mode (N = 1 or 2): maximum of 33 Mbps (2) HDTV recording mode (N = 15): maximum of 33 Mbps As described above, the maximum encoding rate is set in common in any recording mode. Thereby, the same recording / reproducing capability of the optical disk device can be used. Also in this case, the configuration and the modulation method of the error correction code are common. It is desirable that the data amount of the MPEG2 system layer be an integral multiple of 32768 bytes for each GOP.

Next, a moving picture reproducing apparatus corresponding to the above moving picture recording apparatus will be described. FIG. 5 shows a schematic configuration of a moving image reproducing apparatus according to the present embodiment. This moving picture reproducing apparatus basically performs the reverse processing of the moving picture recording apparatus shown in FIG. 1, and includes an optical disc reproducing section 501, a demodulating section 502, an error correction decoding section 503, a recording mode detecting section. 504, system separation unit 505, video decoding unit 50
6 and an audio decoding unit 507, and has a standard TV video output terminal 508, HDTV video output terminal 509, audio output terminal 510, and compressed data output terminal 511 as output terminals.

The optical disk reproducing unit 501 includes an optical pickup, a mechanical unit, a servo control unit, and the like, and reproduces data from a rewritable optical disk. The demodulation unit 502 performs data conversion reverse to the modulation, and performs error correction decoding
In step 03, a data error generated in the recording / reproducing process is corrected.

The recording mode detecting section 504 extracts and identifies a flag indicating a recording mode recorded in a management area or the like at the time of recording from the output of the error correction decoding section 503, and outputs the information to each section of the reproducing apparatus. To supply. The system separation unit 505 separates a video stream and an audio stream from the MPEG2 system stream.

The information indicating the recording mode identified by the recording mode detecting unit 504 is supplied to the video decoding unit 506 and used for setting a decoding mode. That is, the video decoding unit 506 sets the GOP length N to N1 (for example, N1 = 1 or N1 = 2) when the recording mode is the standard TV recording mode, and sets the GOP length N to N2 (for example, N2 for the HDTV recording mode). = 15) and decoding is performed. Then, the video signal decoded by the video decoding unit 506 is
The video signal is output from either the standard TV video output terminal 508 or the HDTV video output terminal 509 in accordance with the recording mode detected by the recording mode detection unit 504.

On the other hand, the audio signal decoded by audio decoding section 507 is output from audio output terminal 510. A bit stream such as an MPEG2 system stream before system separation is output from a compressed data output terminal 511.

In the case of a recording / reproducing apparatus, the moving picture recording apparatus shown in FIG. 1 and the moving picture reproducing apparatus shown in FIG. 5 are incorporated in the same apparatus. In this case, for example, the optical disk recording unit 112 and the optical disk reproducing unit 501 are realized by a substantially common device, and it goes without saying that various memories and the like can be shared between the recording side and the reproducing side. Also, if the output of the stream switching unit 109 of FIG. 1 is input to the system separation unit 505 of FIG.
You can play and check.

As described above, according to this embodiment, the HDTV
GOP when recording video signals and when recording standard TV video signals
The compression encoding is performed at substantially the same encoding rate by changing the length and the picture configuration, and the same error correction encoding processing and modulation processing are performed.

(1) A common device, a standard TV video signal,
Both recording and reproduction of HDTV video signals can be performed. (2) Recording of only one type of recording medium with only standard TV video signals, recording with only HDTV video signals, standard TV / HDTV
It can be used for mixed recording of video signals, and media cost can be reduced due to mass production effects. (3) Regardless of whether a standard TV video signal or an HDTV video signal is recorded, substantially the same SN ratio and recording time can be obtained. (4) In the case of HDTV recording, a high-resolution reproduced video can be obtained. (5) In the case of standard TV system recording, a stream that can be easily edited and played back in reverse can be obtained.

(Second Embodiment) Next, a second embodiment of the present invention will be described. In the present embodiment, the present invention is applied to a camera-integrated video recording / reproducing apparatus which has an imaging unit in the main body and records / reproduces moving image data and audio data compressed and encoded using a rewritable optical disk as a recording medium. It is.

FIG. 6 shows a schematic configuration of a moving image recording apparatus according to the present embodiment. The same parts as those in FIG. 1 are denoted by the same reference numerals and will be mainly described with respect to differences from the first embodiment. In FIG. 6, the standard TV video input terminal 101 and the HDTV video input terminal shown in FIG. 102, the input video switching unit 105 and the audio input terminal 104 are removed, and an imaging unit 601, a sample number conversion unit 602, and an audio input unit 603 are added instead.

The image pickup section 601 is composed of an image pickup element such as a CCD image sensor or a CMOS image sensor, and has an HDTV class pixel number.
In the standard TV recording mode, the number-of-samples conversion unit 602 changes the number of pixels in the standard TV recording mode from the number of pixels in the HDTV system (1920 pixels horizontally by 1080 frame lines) to the number of pixels in the standard TV system (720 pixels horizontally in the luminance signal).
The number of samples is converted to pixels × 486 vertical lines). The conversion of the number of samples mentioned here may be so-called sub-sampling processing by pixel thinning, or may be processing to cut out, for example, a central portion of the HDTV screen as it is. The audio input unit 603 includes a microphone or the like, and supplies the captured audio to the audio encoding unit 107.

As described above, in the present embodiment, the provision of the number-of-samples conversion unit 602 allows the use of the common image pickup unit 601 both when recording in the standard TV mode and when recording in the HDTV mode. The size of the device can be reduced. Of course, in order to reduce the cost, the number of pixels of the image pickup unit 601 is set to about the middle of the number of pixels of the standard TV and the HDTV, and the standard TV / HDTV
, The number of samples can be converted (thinning out in the standard TV recording mode, interpolation in the HDTV recording mode).

FIG. 7 is a diagram showing a schematic configuration of a moving image reproducing apparatus according to the present embodiment. 5 are denoted by the same reference numerals, and only the differences will be described. In FIG. 7, the sample number conversion unit 701, the video display unit 702, and the audio output unit 703 has been added. The video display unit 702 includes a viewfinder, a small liquid crystal monitor, or the like, and displays decoded / reproduced video. Since such an image display unit 702 generally does not always have a sufficient number of pixels, the sample number conversion unit 702 uses the HDTV even in the standard TV recording mode.
Even in the recording mode, conversion to the number of pixels of the video display unit 702 (generally, pixel thinning) is performed. Audio output unit 703
Is composed of a small speaker or the like, and the audio decoding unit 5
In step 07, the decoded sound is output.

In the case of a recording / reproducing apparatus, the moving picture recording apparatus shown in FIG. 6 and the moving picture reproducing apparatus shown in FIG. 7 are incorporated in the same apparatus. In this case, the stream switching unit 10 of FIG.
9 is input to the system separation unit 505 in FIG. 7, the video to be recorded can be displayed on the video display unit 70.
2 and the image can be easily confirmed.

Also in the second embodiment, by changing the length of the GOP and the picture configuration according to the recording mode, encoding is performed at substantially the same encoding rate regardless of the recording mode, and the same error correction encoding is performed. Performing processing and modulation processing is the same as in the first embodiment. The coding rate may be a fixed rate or a variable rate. In the case of a variable rate, the maximum rate is made substantially the same regardless of the recording mode.

As described above, also in this embodiment, the HD
When recording a TV video signal and when recording a standard TV video signal, encoding is performed at substantially the same encoding rate by changing the GOP length and picture configuration, and the same error correction encoding processing and modulation processing are performed. By doing so, it is possible to perform recording and reproduction of both the standard TV video signal and the HDTV video signal with a common device, and using one type of recording medium,
Standard TV video signal only, HDTV video signal only, Standard TV
It can be used as a mixture of V video signals and HDTV video signals.

Also, when recording any video signal, almost the same SN ratio and recording time can be obtained.
When recording a TV video signal, a high-resolution video can be obtained, and when recording a standard TV video signal, a stream that can be easily edited and played back can be obtained.

In particular, in the present embodiment, the recording of both the standard TV video signal and the HDTV video signal can be selectively performed by the common image pickup section, and a compact recording apparatus can be realized.

The present invention is not limited to the first and second embodiments, and various modifications and applications are possible as exemplified below. (1) In the first and second embodiments, a rewritable optical disk is considered as a recording medium, but a write-once optical disk, a magnetic tape, a magnetic disk, an IC memory, a combination thereof, and the like are also possible.

(2) In the first and second embodiments, a single device can record and reproduce both a standard TV video signal and an HDTV video signal. However, only a recording medium and a recording method are used in common. The device may be configured to record and reproduce only one of the standard TV video signal and the HDTV video signal. Further, for example, the recording may be performed only in the HDTV mode, and the reproduction may be performed in an apparatus capable of both the HDTV mode and the standard TV mode.

(3) In the first and second embodiments, the standard T
Although the same video encoding unit and video decoding unit were used for the V video signal and the HDTV video signal, the position of the switching unit was changed, and a dedicated encoding unit and a dedicated encoding unit for the standard TV video signal and the HDTV video signal were used. A decoding unit may be provided.

Further, for example, a moving picture recording / reproducing apparatus is provided with only an encoding section and a decoding section for an HDTV video signal, and the encoding section and the decoding section for a standard TV video signal are externally provided. The compressed standard TV data may be input / output using the data input / output terminal.

(4) The compression method is not necessarily limited to MPEG2. When the GOP length (N) is 1, the MPE
If G2 is used, the data amount becomes somewhat redundant,
MPEG2 for TV video signals, J for standard TV video signals
Different compression methods may be used, such as using PEG respectively.

(5) In the first and second embodiments, it is assumed that video and audio are recorded and reproduced in a multiplexed form, but video and audio may be separately recorded and reproduced. (6) In the above description, for convenience, standard TV and HDT
Although the term V is used, the present invention is not limited to this, and the present invention can be applied to two or more types of television systems having different effective pixel rates.

(7) In the above description, N = 1, N = 2, and N = 15 have been taken as examples of the GOP length N. However, other values can be of course selected. (8) In the first and second embodiments, the processing of the moving image recording device and the moving image reproducing device has been described as being realized by hardware. It is also possible to execute with.

[0089]

As described above, according to the present invention, 1
It is possible to record / reproduce two types of moving image signals based on television systems having different effective pixel rates, such as a standard TV and an HDTV, using a recording medium such as a rewritable optical disk. A moving image recording device and a moving image reproducing device that record / reproduce these two types of moving image signals can be provided.

More specifically, a common device uses a standard TV,
It can record / reproduce both HDTV video signals, and can use only one type of recording media, such as only standard TV video signals, only HDTV video signals, and mixed standard TV / HDTV video signals. Furthermore, almost the same S / N ratio and recording time can be obtained regardless of which video signal is recorded.

In addition, when recording an HDTV video signal, a high-resolution video can be obtained, and when recording a standard TV video signal, a stream that can be easily edited and played back in reverse can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration of a moving image recording apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram showing examples of various GOP configurations.

FIG. 3 is a diagram showing an example of a change in the code amount for each picture when the GOP length is variously changed.

FIG. 4 is a diagram illustrating a configuration example of an error correction code.

FIG. 5 is a block diagram showing a schematic configuration of a moving image reproducing apparatus according to the first embodiment of the present invention.

FIG. 6 is a block diagram showing a schematic configuration of a moving image recording apparatus according to a second embodiment of the present invention.

FIG. 7 is a block diagram showing a schematic configuration of a moving image reproducing apparatus according to a second embodiment of the present invention.

[Explanation of symbols]

 101: Standard TV video input terminal 102: HDTV video input terminal 103: Compressed data input terminal 104: Audio input terminal 105 ... Input video switching unit 106 ... Video encoding unit 107 ... Audio encoding unit 108 ... System multiplexing unit 109 ... Stream Switching unit 110: Error correction encoding unit 111: Modulation unit 112: Optical disk recording unit 113: Recording mode setting unit 501: Optical disk reproduction unit 502: Demodulation unit 503: Error correction decoding unit 504: Recording mode detection unit 505: System separation Unit 506 video decoding unit 507 audio decoding unit 508 standard TV video output terminal 509 HDTV video output terminal 510 audio output terminal 511 compressed data output terminal 601 imaging unit 602 sample number conversion unit 603 audio Input unit 701: sample number conversion 702 ... the video display unit 703 ... audio output unit

Claims (13)

[Claims] An encoding means for compressing and encoding an input moving image signal in an independently decodable unit having an arbitrary number of screens. A video signal of a first television system having a first effective pixel rate in the encoding means and a second television system having a second effective pixel rate higher than the first effective pixel rate Means for selectively inputting any one of the moving image signals of the first television system, and the encoding unit is included in an independently decodable unit when the moving image signal of the first television system is input. A moving picture characterized in that the relationship between the number of pictures N1 and the number of pictures N2 included in an independently decodable unit when a moving picture signal of the second television system is input is N1 <N2, and compression encoding is performed. Recording equipment . 2. A moving picture recording apparatus for compressing and coding a moving picture signal and recording it on a recording medium, wherein said coding means compresses and codes the inputted moving picture signal in an independently decodable unit having an arbitrary number of screens. An imaging unit that captures a moving image and outputs a moving image signal; a first television system moving image signal having a first effective pixel rate, the moving image signal output from the imaging unit; Converting means for converting the video signal into one of video signals of a second television system having a second effective pixel rate higher than that of the first television system and inputting the video signal to the encoding unit; The encoding means includes a number N1 of screens included in an independently decodable unit when the video signal of the first television system is input and a number of screens N1 when the video signal of the second television system is input. Independence A moving image recording apparatus characterized in that the relationship between the number of screens N2 included in a codeable unit and N1 <N2 is set to perform compression encoding. 3. The coding means according to claim 1, wherein said coding means is configured to calculate an average coding rate or a coding rate when the moving image signal of the first television system is inputted and when the moving image signal of the second television system is inputted. 3. The compression encoding is performed so that the maximum encoding rates are substantially the same.
5. The moving image recording device according to item 1. 4. A method according to claim 1, wherein said first television type moving image signal is inputted to said encoding means with respect to a signal recorded on said recording medium, and said second television type moving image signal is inputted to said encoding means. The moving picture recording apparatus according to any one of claims 1 to 3, further comprising processing means for performing the same error correction coding processing and modulation processing when a signal is input. 5. A method for identifying whether a moving image signal input to said encoding means is a moving image signal of the first television system or a moving image signal of the second television system. 5. The apparatus according to claim 1, further comprising: means for recording a flag on the recording medium.
12. The moving image recording device according to item 13. 6. The first television system has 720 horizontal pixels and 480 pixels or 486 vertical pixels of luminance signal effective pixels per frame, and the second television system has one frame per frame. The moving image recording apparatus according to any one of claims 1 to 5, wherein the moving image recording apparatus has a luminance signal effective pixel of 1920 pixels in a horizontal direction and 1035 pixels or 1080 pixels in a vertical direction. 7. The first television system has 720 horizontal pixels and 480 pixels or 486 vertical pixels of luminance signal effective pixels per frame, and the second television system has one frame per frame. It has 1920 pixels in the horizontal direction and 1035 pixels or 1080 pixels in the vertical direction, and the encoding means has N1 = 1 or N1 = 2.
The moving image recording apparatus according to claim 1, wherein N2 is set to N2 = 15. 8. The encoding means according to claim 1, wherein said first television system video signal is inputted and said second television system video signal is inputted.
8. The moving image recording apparatus according to claim 7, wherein the compression encoding is performed so as to have substantially the same average encoding rate of not less than ps and not more than 28 Mbps. 9. A moving image signal of a first television system having a first effective pixel rate and a moving image signal of a second television system having a second effective pixel rate higher than the first effective pixel rate. What is claimed is: 1. A moving image reproducing apparatus for reproducing a moving image signal from a recording medium in which one of image signals is compression-coded and recorded, wherein the first television system is provided on the recording medium from the recording medium. Detecting means for detecting a flag for identifying whether a moving image signal is recorded or a moving image signal of the second television system is recorded; and the recording medium according to a detection result by the detecting means The number of screens N1 included in the independently decodable unit when the moving image signal of the first television system is recorded above and the moving image signal of the second television system is recorded Moving image reproduction apparatus, wherein a relationship between the screen number N2 included independently decodable units and and a decoding means for performing decoding as N1 <N2. 10. A moving picture signal of the first television system and a moving picture signal of the second television system recorded on the recording medium with respect to a signal reproduced from the recording medium. 10. The moving image reproducing apparatus according to claim 9, further comprising processing means for performing the same demodulation processing and error correction decoding processing when a signal is recorded. 11. A moving image recording method for compressing and encoding a moving image signal and recording the same on a recording medium, comprising: a moving image signal of a first television system having a first effective pixel rate; Second higher than rate
One of the video signals of the second television system having an effective pixel rate of, and included in the independently decodable unit when the video signal of the first television system is inputted. The relationship between the number of screens N1 to be displayed and the number of screens N2 included in the independently decodable unit when the video signal of the second television system is input is expressed as N1 <
N2, and the average coding rate or the maximum coding rate is substantially the same when the video signal of the first television system is input and when the video signal of the second television system is input. The compression encoding is performed so that the moving image signal after the compression encoding is input with the moving image signal of the first television system and the moving image signal of the second television system. The same error correction coding process and modulation process are performed when a signal is input, and the moving image signal of the error correction coding process and the modulation process is a video signal of the first television system. 2. A moving image recording method, comprising: recording on the recording medium together with a flag for identifying whether the signal is a moving image signal of the television system. 12. A moving image signal of a first television system having a first effective pixel rate and a moving image signal of a second television system having a second effective pixel rate higher than the first effective pixel rate. A moving image reproducing method for reproducing a moving image signal from a recording medium on which any one of the image signals is selectively compression-encoded and recorded, wherein a signal reproduced from the recording medium is recorded on the recording medium. Performs the same demodulation processing and error correction decoding processing as when the video signal of the first television system is recorded and when the video signal of the second television system is recorded. A file from the recording medium for identifying whether a moving image signal of the first television system or a moving image signal of the second television system is recorded on the recording medium; In accordance with the detection result of the flag, the number of screens N1 included in the independently decodable unit when the video signal of the first television system is recorded on the recording medium and the The relationship between the number of screens N2 included in the independently decodable unit when a moving image signal of the TV system 2 is recorded is expressed as N
A moving image reproducing method, wherein decoding is performed with 1 <N2. 13. A recording medium on which a moving image signal is compression-encoded and recorded, wherein the moving image signal is a moving image signal of a first television system having a first effective pixel rate. A recording medium characterized by recording a flag for identifying whether the video signal is a video signal of a second television system having a second effective pixel rate higher than the first effective pixel rate.