JPH06181563A - Digital video recorder for edtv television signal - Google Patents

Abstract

PURPOSE:To reduce the deterioration of picture quality even in the case of an uncorrectable code error by substituting the vertical reinforcing signal of a zero component for the uncorrectable code error generated from the upper and lower pictureless part areas of a letter box type EDTV signal screen. CONSTITUTION:An external code ECC decoding part 15 prepares signals EFG1, EFG2 indicating code error areas for uncorrectable code errors. A code error correcting part 17 executes error correcting processing for substituting a zero component signal for an uncorrectable code error in the upper and lower pictureless part areas of the letter box type EDTV signal screen and substituting a picture signal having high correlation for the error in a picture area. A D/A conversion part 18 converts the processed signal into an analog signal to obtain a reproduced output signal V0. Consequently high quality pictures can be recorded/reproduced from any of TV signals NTSC, EDTV, and even when an uncorrectable code error is generated, the deterioration of picture quality can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television signal digital recording apparatus, and more particularly to an NTSC signal and an N signal.
Letterbox EDT compatible with TSC signals
The present invention relates to a digital recording device for television signals suitable for recording and reproducing V signals.

[0002]

2. Description of the Related Art Research and development of a new television system for providing a more realistic image service by improving image quality, definition of a television image, widening a screen, and the like are under way. Among them, EDTV has compatibility with the current television system (NTSC) and has a wider screen,
It is intended to realize higher definition, and is being studied as a next-generation TV system.

Various types of EDTV have been devised. Among them, the letterbox type EDTV is
A horizontally long image having a horizontally long aspect ratio is transmitted and received by providing non-image areas on the top and bottom of the screen. Then, a vertical high-frequency component is superimposed as a vertical reinforcement signal in the upper and lower non-image areas of the screen in order to improve the vertical resolution.

The television signal of the letterbox EDTV is compatible with the receiver, and a horizontally long image having a horizontally long aspect ratio can be received even when received by the current television receiver. Further, since the transmission paths are compatible with each other, it is possible to record this signal even in the recording apparatus of the current television system. Therefore, a letterbox EDTV signal can be recorded by a conventional digital recording device such as a D2 type digital VTR already commercialized.
Can be played.

[0005]

[Problems to be Solved by the Invention] Letterbox method E
In the DTV signal, the image area is NTSC of the current television system.
The signal has the same form as the signal. On the other hand, vertical reinforcement signals having different properties from the image area are superimposed on the non-image areas on the top and bottom of the screen. That is, the vertical reinforcement signal is a signal having extremely small redundancy and less correlation than the signal in the image area.

In the digital recording according to the conventional technique, an error correction process is carried out in which uncorrectable code errors are replaced with a signal having a strong correlation, for example, a signal in the previous field by utilizing the redundancy of the image signal. Therefore, in the digital recording of the letterbox EDTV signal according to the conventional technique, even an uncorrectable code error in the upper and lower non-image areas is subjected to error correction processing by replacing the vertical reinforcement signal in the previous field. That is, the correction is performed with a signal having a small correlation. However, in the letterbox EDTV receiver, the vertical high frequency component obtained by demodulating the vertical reinforcement signal is added to the image signal to reproduce the image. Therefore, in the EDTV signal subjected to the error correction processing according to the related art, the image is reproduced with an erroneous vertical high frequency component different from the normal one due to the correction of the vertical reinforcement signal by the signal having a small correlation, and the image quality is significantly deteriorated. .

That is, in the digital recording according to the conventional technique, common error correction processing is performed for both the vertical reinforcement signal of the non-image area above and below the screen of the EDTV signal and the image signal of the horizontally long image area. However, there is a problem that a remarkable image quality deterioration occurs due to this error correction processing.

The object of the present invention is to achieve letterbox method E, in which image quality deterioration is extremely small even for uncorrectable code errors.
It is to provide a digital recording device for a DTV signal.

[0009]

To achieve the above object, according to the present invention, an uncorrectable code error is a component of which the vertical reinforcement signal is zero in the non-image areas above and below the screen of a letterbox EDTV signal. The error correction processing technique of replacing with an image signal and replacing with an uncorrectable code error in the image area is performed with an image signal having a strong correlation similar to the conventional technique.

[0010]

According to the present invention, an uncorrectable code error occurring in the upper and lower non-image areas of the screen of a letterbox EDTV signal is replaced with a vertical reinforcement signal having a zero component for error correction processing. Therefore, in the letter box type EDTV receiver, the vertical reinforcement signal subjected to the error correction is demodulated as a signal having zero vertical high frequency components and added to the image signal. As a result, it is possible to completely eliminate the image quality deterioration caused by the reproduction of the image due to the vertical high frequency component different from the normal, which is a problem in the conventional technique.

On the other hand, in the present invention, the letterbox system E
Uncorrectable code errors occurring in the image area of the DTV signal are replaced by an image signal having a strong correlation using image redundancy as in the prior art, and therefore error correction processing with extremely little deterioration in image quality can be performed. it can.

Further, according to the present invention, the NT of the current television system is used.
Digital recording is performed on the SC signal as in the prior art. Therefore, it is possible to realize a digital recording apparatus that records and reproduces both NTSC signals and letterbox EDTV signals with high quality images.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to the block diagram shown in FIG. This is suitable for digitally recording an NTSC signal or a letterbox EDTV signal as a PCM encoded signal.

The input television signal VS (NTSC signal, letterbox EDTV signal) is sampled by the A / D converter 1 at a frequency four times as high as the color subcarrier f _sc of the NTSC signal, and PCM is performed. Convert to encoded signal.

The channel division unit 2 divides the PCM-coded signal into a plurality of channels (in practice, four-channel division or the like is adopted, but here, for simplification of the drawing, two-channel division is shown as an example).

In order to correct a code error such as a random error or a burst error included in the reproduced signal, an error correction code (hereinafter abbreviated as ECC) is used by the outer code ECC encoder unit 3, the shuffling unit 4, and the inner code ECC encoder unit 5. Is added. That is, a code structure is adopted in which an outer code and an inner code are formed by a chain structure of ECC, and random errors and short burst errors are corrected by the inner code and long burst errors that cannot be corrected by the inner code by the outer code are respectively adopted and corrected. The code of the inspection point necessary for is added. Further, in order to increase the length of a correctable burst error, shuffling processing for rearranging pixels in time is also performed. The ECC uses Reed-Solomon code or the like for correction on a pixel-by-pixel basis.

The channel encoder unit 6 converts the m-bit code into an n-bit code (n> m) by mn conversion processing to convert the code sequence into a DC-balanced code sequence. Further, an identification code ID (consisting of a synchronization code, a channel, a field and a block number information code) created by the SYNC generator 7 is added. Then, the signal is recorded on the recording medium 9 through the recording amplifier 8.

On the other hand, the reproduced signal from the recording medium 9 is converted into an original m-bit code by an mn conversion process in a channel decoder section 11 through a reproduction amplifier 10.

The SYNC detector 12 detects the sync code of the identification code ID and reproduces the information of the channel, field and block number.

The inner code ECC decoder unit 13 performs error correction processing using the inner code and corrects random errors and short burst errors.

In the deshuffling unit 14, the pixels are temporally rearranged to be decoded into the original time series code. Then, the outer code ECC decoder unit 15 corrects the error remaining without being corrected by the inner code by the error correction process using the outer code. Then, for uncorrectable code errors, signals EFG1 and EFG2 indicating the area of the code error are output.

The channel integration unit 16 integrates signals of a plurality of channels to form a signal VSD and a signal EFG indicating an uncorrectable code error area.

The code error correction unit 17 replaces an uncorrectable code error with a signal having a zero component in the non-image area above and below the screen of the letterbox EDTV signal, and an image signal having a strong correlation in the image area. Perform error correction processing to replace with. The NTSC signal is subjected to error correction processing by replacing the image signal with a strong correlation. Then, the D / A conversion unit 1
At 8, the signal is converted into an analog signal to obtain a reproduction output signal V0.

Next, each block portion of this embodiment will be described. It should be noted that each block unit except for the code error correction unit can be easily realized with the same configuration as that of the conventional technique, and thus the description thereof will be omitted.

FIG. 2 shows an outline of signal processing in the code error correction unit. The figures (a) and (b) are respectively NTSC.
Signal, error correction processing for letterbox EDTV signal, (c) shows an example of one correction of image signal.

In the NTSC signal, the signal in the uncorrectable code error area shown by the shaded area in FIG. 9A is subjected to error correction processing in which the signal in the previous field (the signal 262 lines before) is replaced, for example. That is, as shown in FIG. 7C, the signals of the uncorrectable scanning lines in the current field are replaced with the signals of the scanning lines A and B in the previous field.

In the letterbox type EDTV signal, as shown in FIG. 2B, an error correction process is performed to replace an uncorrectable code error signal in the image area with the signal in the previous field as in the NTSC signal. . On the other hand, an uncorrectable code error signal in the upper and lower non-image areas of the screen is replaced with a signal having a zero signal component to perform error correction processing.

FIG. 3 shows a first embodiment of the code error correction unit 17. Control signal C1 generated by the modification control circuit 24
To C4, the field memory circuit 19 and the selection circuit 2
The operations of 1, 22, 23 are controlled to realize the above-mentioned error correction processing. The field memory circuit 19 uses the signal VSD
Information is written and a signal FDS delayed by one field period (262 line periods) is output. It should be noted that during the period of uncorrectable code error of the signal VSD, the control signal C1
Write operation is prohibited by. Chroma inversion circuit 20
Then, a signal -FDS in which the polarities of the color signal components are inverted is created. In the selection circuit 21, the signal VSD is generated by the control signal C2.
And a signal whose color signal components have the same phase are selected and output as a signal CV. This signal is used as a retouching signal for the image area. In the selection circuit 22, the control signal C3 selects the signal CV in the image area and the signal CH (a signal corresponding to zero in the component of the vertical reinforcement signal) in the upper and lower non-image areas of the screen of the letterbox EDTV. Then, the correction signal CS is generated. Then, in the selection circuit 23, the control signal C
The correction signal CS is selected and output in the period of the uncorrectable code error due to 4, and the signal VSC subjected to the error correction processing by the replacement with the correction signal CS is generated.

FIG. 4 shows a second embodiment of the code error correction unit 17. Control signal C generated by the modification control circuit 24
2 to C4 control the operations of the selection circuits 21, 22, and 23 to implement the error correction processing described above. The field memory circuit 19 writes the information of the signal VSC and outputs the signal FDS which is delayed by one field period (262 line periods). In the selection circuit 21, the control signal C2 selects the signal FDS and the signal -FDS in which the polarities of the color signal components are inverted by the chroma inversion circuit 20, and the signal VSD and the signal in which the color signal components have the same phase. The signal CV used for the modification is output. Further, in the selection circuit 22, the letter box type EDTV is set by the control signal C3.
The signal CH (vertical reinforcement signal whose signal component corresponds to zero) is displayed in the upper and lower non-image areas of the screen, and the signal CV is selected and output in the other image area to generate the retouching signal CS.
Then, the selection circuit 23 selects and outputs the correction signal CS during the period of the uncorrectable code error by the control signal C4 to generate the signal VSC subjected to the error correction processing.

FIG. 5 shows an embodiment of the modification control circuit 24 in these embodiments. FIG. 5A shows the configuration and FIG. 5B shows the form of the control signals C1 to C4. The signal EFG indicating the uncorrectable code error area is latched by the latch circuit 52, and the control signals C1 and C4 of H are generated during the uncorrectable code error period and L in the other areas. In the system identification circuit 53,
The letterbox ED is detected by detecting the identification signal added to the letterbox EDTV signal.
The TV signal and the NTSC signal are discriminated. In the case of the letterbox EDTV signal, the period of the non-image area above and below the screen is H, and L and NTS in other areas.
In the case of the C signal, the L control signal C3 is generated. Further, the color phase comparison circuit 54 compares the phases of the color signal components based on the burst signals of the signals VSD and FDS, and produces the control signal C2 of L in the case of in-phase and H in the case of opposite phase.

As described above, according to the present embodiment, a digital recording apparatus capable of recording / reproducing a high quality image of a television signal of any of the letter box type EDTV and the current NTSC type is provided. Can be realized.

Next, a second embodiment of the present invention will be described with reference to FIG. This is suitable for compressing the amount of recorded information by performing digital recording with a signal obtained by highly efficiently encoding an NTSC signal and a letterbox EDTV signal.

The input television signal VS (NTSC signal, letterbox EDTV signal) is sampled by the A / D converter 1 at, for example, a frequency four times as high as the color subcarrier f _{sc to obtain} a digital signal VDS. Convert to.

In the high efficiency coding unit 25, for example, the DPC
High-efficiency coding processing such as M-prediction coding, sub-Nyquist sampling, DCT (discrete cosine transform) conversion coding is performed to generate a signal VBS in which the amount of information is compressed. And
The channel division unit 2 divides the signal into a plurality of channels (the figure shows an example of 2-channel division).

The outer code ECC encoder unit 3, the shuffling unit 4, and the inner code ECC encoder unit 5 add the code of the ECC check point necessary for correcting the code error contained in the reproduced signal. That is, a code configuration is used in which the ECC is configured in a chain form to form an outer code and an inner code, and the inner code corrects random errors and short burst errors, and the outer code corrects long burst errors that cannot be corrected by the inner code. The codes of the inspection points necessary for correction are added. Also, in order to increase the length of correctable burst errors, shuffling processing is performed to rearrange signal sequences in time. A Reed-Solomon code or the like is used for the ECC.

In order to convert the recording signal into a DC balanced signal, the channel encoder section 6 carries out an m-n conversion process for converting an m-bit code into an n-bit code (n> m). In addition, the identification code ID created by the SYNC generator 7
(Composed of synchronization code, block code, etc.) is added. Then, the signal is recorded on the recording medium 9 through the recording amplifier 8.

On the other hand, the signal reproduced from the recording medium 9 by the reproducing amplifier 10 is converted into the original m-bit code by the channel decoder section 11 by the nm conversion process.

The SYNC detecting section 12 solves the sync code of the identification code ID and reproduces the block codes which need decoding.

The inner code ECC decoder unit 13 corrects random errors and short burst errors using the inner code.
Then, in the deshuffling unit 14, the signal sequence is temporally rearranged to be decoded into the original time-series signal. Then, the outer code ECC decoder unit 15 corrects the remaining long burst error that cannot be corrected by the inner code. For a code error that cannot be corrected even by the error correction process using the outer code, the signals EFG1 and EFG2 indicating the area of the code error are displayed.
Is output.

The channel integration unit 16 integrates signals of a plurality of channels and outputs a signal VBS and a signal EF indicating an uncorrectable code error area.

The high efficiency decoding unit 26 performs a predetermined decoding process to decode the original digital signal VDS. together,
A signal EFG indicating the area including the code error signal is output.

The code error correction unit 17 performs error correction processing for replacing the signal in the code error area with the correction signal. In this case, the vertical reinforcement signal corresponding to a signal having zero component is used in the acid regions of the non-image area above and below the screen of the letterbox EDTV signal, and the signal of the front field having a strong correlation in the image area is used as the correction signal. Then, the signal VSC subjected to the error correction processing is converted into an analog signal by the D / A conversion unit 18, and the reproduction output signal V0 is obtained.

In the following, the high efficiency coding unit 25 and the decoding unit 26 in this embodiment will be described based on the embodiment. The code error correction unit 17 can be realized by the embodiment shown in FIG. 3 to FIG. 5, and the other block units can be realized by the same configuration as that of the conventional technique, and therefore the description thereof will be omitted.

FIG. 7 shows an embodiment in which high-efficiency coding is performed by DPCM predictive coding. FIG. 7A shows the structure of a recording system encoding unit, and FIG. 7B shows the structure of a reproducing system decoding unit. Indicates.

In the encoding unit, the signal VDS and the signal delayed by one pixel in the one-pixel delay circuit 27 are input to the difference circuit 28, and the difference between the two signals is calculated to generate the difference signal VE. . Then, the quantizing circuit 29 quantizes this difference signal and converts it into a code VEQ. The entropy coding circuit 30 performs entropy coding in which a code having a high occurrence probability is assigned a short code length, and a code having a low probability of short life is assigned a long code length. Then, the signal VBS in which the amount of information is compressed is generated.

In the decoding section, the entropy decoding circuit 31
Then, the variable length coded signal VBS is decoded into the original fixed length code VEQ by a predetermined decoding process. Inverse quantization circuit 3
In 2, the original difference signal VE is demodulated by the inverse quantization process. Then, the adder circuit 33 adds the signal VE to the output signal of the one-pixel delay circuit 27 to decode the original signal VSD.
On the other hand, the error area setting circuit 55 extracts the area of the code error propagated by the decoding process and creates the signal EFG indicating the area containing the uncorrectable code error.

FIG. 8 shows an embodiment of high-efficiency coding by sub-Nyquist sampling. FIG. 8A is a coding unit, and FIG. 8B is a coding unit.
Indicates the configuration of the decoding unit.

In the encoding unit, the pre-filter unit 34 performs a predetermined frequency band limitation in order to avoid mixing of aliasing components due to sub-Nyquist sampling, and removes signal components that cause aliasing distortion. The sample point sub-sampling unit 35 performs a predetermined sample point thinning-out process, and converts it into a signal of sub-Nyquist sampling in which the number of sample points is reduced to 1/2, for example. Then, the time-axis compression unit 36 performs a time-axis 1/2 compression process to generate a signal VBS whose information amount has been compressed to 1/2.

In the decoding section, the signal VBS is doubled in the time axis by the time axis expansion section 37. The sampling point interpolating unit 38 inserts a zero value into the sampling points that have been skipped by the sub-Nyquist sampling, and converts the sampling points into signals of the original sampling form. And
The post filter unit 39 extracts a signal component in a predetermined frequency band and decodes it into the original signal VSD. On the other hand, the error area setting circuit 56 extracts the area where the code error is propagated by the decoding process, and creates the signal EFG indicating the area including the uncorrectable code error.

9A and 9B show an embodiment of high efficiency coding by DCT (discrete cosine transform) transform coding. FIG. 9A shows the configuration of the encoding unit, and FIG. 9B shows the configuration of the decoding unit.

In the encoding unit, the YC separation unit 40 performs, for example, separation processing of luminance and color signals according to horizontal and vertical two-dimensional characteristics, and separates into luminance component SY and color component SC of the image area. The signal VH in the upper and lower non-image areas of the screen of the letterbox EDTV is separated as a luminance component. In the DCT conversion unit 41, for example, one block is composed of 8 × 8 pixels composed of horizontal and vertical 8 pixels, and a DCT matrix is operated on the signal of the block to obtain the DCT
The conversion coefficients DY and DC are generated. The quantizer 42 performs quantization with a predetermined quantization characteristic to generate codes DYQ and DYC. The entropy coding unit 43 performs variable length coding processing in which a code having a short code length is assigned to a code having a high occurrence probability. Then, the multiplexing unit 44 time-division multiplexes both signals and compresses the information amount to obtain the signal VBS.
To generate.

In the decoding unit, the signal VBS is separated by the demultiplexing unit 45 into signals of two systems. The entropy decoding unit 46 converts a variable-length code into fixed-length codes DYQ and DCQ by a predetermined decoding process. The inverse quantization circuit 47 decodes the original DCT transform coefficients DY and DC by a predetermined inverse quantization process. The inverse DCT conversion unit 48 performs an operation using an inverse DCT matrix to decode the original luminance component SY and color component SC. Then, the adder circuit 49 adds both signals and decodes the original signal VSD. On the other hand, the error area setting circuit 57 extracts the area where the code error is propagated by the decoding process, and creates the signal EFG indicating the area including the uncorrectable code error.

FIG. 10 shows an embodiment of high-efficiency coding by motion-compensated interframe predictive coding and DCT transform coding. FIG. 10A shows the configuration of a coding unit and FIG. 10B shows the configuration of a decoding unit. Show.

In the encoding section, the YC separation section 40 separates the luminance and chrominance signals with, for example, horizontal and vertical two-dimensional characteristics, and separates them into the luminance component SY and the color component SC. The signal VH in the upper and lower non-image areas of the screen of the letterbox EDTV is separated as a luminance component. In the motion compensation interframe predictive coding unit 50, the signal of the current frame,
A predetermined predictive coding process for extracting the difference from the signal of the previous frame that has been motion-compensated by the motion vector is performed to generate error signals YE, CE and motion vectors YMV, CMV. In the DCT conversion unit 41, for example, 8 × 8 pixels composed of horizontal and vertical 8 pixels are set as one block, and a signal of each block is calculated with a DCT matrix to generate DCT conversion coefficients DY and DC. The quantizer 42 performs quantization with a predetermined quantization characteristic, and a code DY having a fixed code length.
Convert to Q, DCQ. In the entropy encoding unit 43,
Variable length coding processing is performed in which a code having a short code length is assigned to a code having a high occurrence probability. Then, the multiplexing unit 44 multiplexes both signals in a time division manner to generate a signal VBS whose information amount is compressed.

In the decoding unit, the signal VBS is separated by the demultiplexing unit 45 into the original two-system signals. The entropy decoding unit 46 decodes the variable-length code into the original fixed-length codes DYQ and DCQ and the motion vectors YMV and CMV by a predetermined decoding process. In the inverse quantization circuit 47, the original DCT transform coefficient D
Decode Y, DC. In the inverse DCT converter 48, the inverse DCT
The original signals YE and CE are decoded by performing the calculation using the T matrix. The motion-compensated inter-frame prediction decoding unit 51 performs a predetermined decoding process using the error signals YE and CE and the motion vectors YMV and CMV to decode the original luminance component SY and color component SC. Then, the adder circuit 49 adds both signals and decodes the original signal VSD. On the other hand, the error area setting circuit 58 extracts the area where the code error is propagated by the decoding process, and produces the signal EFG indicating the area including the uncorrectable code error.

The high-efficiency coding can be realized by a combination of various predictive coding techniques other than these embodiments.

According to the present embodiment, EDTV, current NTSC
It is possible to realize a digital recording apparatus capable of recording / reproducing a high-quality image with a small amount of recorded information in a television signal of any of the above methods.

[0058]

According to the present invention, it is possible to provide a digital recording apparatus which records and reproduces both NTSC and EDTV television signals with a high quality image and has little deterioration in image quality even with uncorrectable code errors. can do.

[Brief description of drawings]

FIG. 1 is a block diagram of a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of signal processing for correcting a code error according to the present invention.

FIG. 3 is a block diagram of a first embodiment of a code error correction unit.

FIG. 4 is a block diagram of a second embodiment of a code error correction unit.

FIG. 5 is a block diagram of an embodiment of a modification control circuit.

FIG. 6 is a block diagram of a second embodiment of the present invention.

FIG. 7 is a block diagram of a first embodiment of a high efficiency encoding unit and a decoding unit.

FIG. 8 is a block diagram of a second embodiment of a high efficiency encoding unit and a decoding unit.

FIG. 9 is a block diagram of a third embodiment of a high efficiency encoding unit and a decoding unit.

FIG. 10 is a block diagram of a fourth embodiment of a high efficiency encoding unit and a decoding unit.

[Explanation of symbols]

1 ... A / D converter, 2 ... Channel divider, 3 ... Outer code E
CC encoder section, 4 ... Shuffling section, 5 ... Inner code E
CC encoder section, 6 ... Channel encoder section, 7 ... S
YNC generator, 8 ... Recording amplifier, 9 ... Recording medium, 10 ...
Reproducing amplifier, 11 ... Channel decoder section, 12 ... SYN
C detection unit, 13 ... Inner code ECC decoder unit, 14 ... Deshuffling unit, 15 ... Outer code ECC decoder unit, 16 ...
Channel integration unit, 17 ... Code error correction unit, 18 ... D / A
Converter.

Claims (6)

[Claims] 1. A digital recording device for an EDTV television signal for transmitting an NTSC signal and a landscape image having a landscape aspect ratio different from that of the NTSC signal by providing a non-image area above and below a screen. NTS
A means for discriminating between the C signal and the EDTV signal, a means for generating a first correction signal by a television signal having a strong correlation in the horizontal, vertical, and temporal three-dimensional regions, and a means for generating a second correction signal by a signal having zero component Means for replacing the uncorrectable code error in the image part area of the NTSC signal or the EDTV signal with the first correction signal, and the uncorrectable code error in the non-image part areas of the upper and lower parts of the screen of the EDTV signal. The second
A digital recording device for EDTV television signals, characterized in that error correction processing is performed by replacement with the correction signal. 2. The digital recording apparatus for an EDTV television signal according to claim 1, wherein the television signal is a signal obtained by PCM-encoding the NTSC signal and the EDTV signal. 3. The digital recording apparatus for an EDTV television signal according to claim 1, wherein the television signal is a signal obtained by highly efficient encoding the NTSC signal and the EDTV signal by DPCM predictive encoding. 4. The digital recording apparatus for an EDTV television signal according to claim 1, wherein the television signal is a signal which is highly efficient encoded by sub-Nyquist sampling of the NTSC signal and the EDTV signal. 5. The digital recording device for an EDTV television signal according to claim 1, wherein the television signal is a signal obtained by performing high-efficiency coding by DCT (discrete cosine transform) conversion coding of the NTSC signal and the EDTV signal. . 6. The EDTV television signal according to claim 1, wherein the television signal is a signal obtained by highly efficient coding of motion compensation interframe predictive coding and DCT conversion coding of the NTSC signal and EDTV signal. Digital recording device.