JPH06343183A - Recording and reproducing device, recorder, reproducing device and recording and reproducing method - Google Patents

Abstract

PURPOSE:To provide a recording and reproducing device and a recording and reproducing method capable of recording and reproducing the signals of the almost entire bands of the signals obtained by decoding MUSE signals as they are using a recording medium whose recording band is narrow by recording and reproducing the MUSE signals in the intermediate stage of the process of the decoding. CONSTITUTION:The decoding processing is performed upto an interframe interpolation processing (a circuit 4) on a recording side and recording is performed as the signals of a stage for not receiving the substantial influence of the distortion of a recording and reproducing system (a medium and the recording and reproducing device). Thus, the ringing of reproducing pictures and the distortion of an edge part can be substantially reduced. Further, on a reproducing side, folded present signal components equal to or more than 12MHz (the high band components of a horizontal frequency band) are utilized (the circuit 105) and reproduced signals having the band width of 20MHz are obtained. Thus, even when the recording medium whose recording band is narrow is used, the resolution and S/N of the reproduced pictures can drastically be improved.

Description

Detailed Description of the Invention

[0001]

[0001]

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording / reproducing apparatus and a recording / reproducing method. The present invention particularly records and reproduces a MUSE signal (a signal obtained by band-compressing a high-definition television signal) at an intermediate stage of the decoding process, thereby using a recording medium having a narrow recording band to record the MUSE signal. It is an object of the present invention to provide a recording / reproducing apparatus and a recording / reproducing method capable of recording / reproducing a signal in the same entire band as a signal obtained by directly decoding a signal.

[0003]

[0002]

[0004]

2. Description of the Related Art A MUSE system has been proposed in which a high-definition television signal is compressed and can be transmitted by satellite broadcasting, and a test broadcasting is being conducted.

[0005]

The MUSE method is described in various documents (for example, P. of "Nikkei Electronics", November 2, 1987, published by Nikkei Electronics Co., Ltd.).
189 to P212 "Transmission system for high-definition broadcasting using satellite MUSE", etc.), and detailed description thereof is omitted here.

[0006]

The luminance (Y) signal transmitted by the MUSE system and decoded by the MUSE decoder has a frequency band covering about 20 MHz as shown in FIG.
The decoding process of still image system in MUSE decoder is as follows.
Roughly, AD conversion → de-emphasis processing → interpolation between frames → interpolation between fields.

[0007]

As shown in FIG. 3, signals decoded by the MUSE decoder (luminance signal Y, color signals Pb, P
In order to record r) on a recording medium and reproduce it from the recording medium as shown in FIG. 4, a recording band of 20 MHz is required only for the Y signal, and a very expensive recording medium or recording / reproducing apparatus for business use is required. Met. (Note that the recording mediums mentioned here may be disc-shaped, tape-shaped, optical, magnetic, or the like.)

[0008]

[0006] Therefore, conventionally, the recording / reproducing band is 12 to 1 in a low-cost, high-definition television recording medium for home use.
The thing of about 3 MHz was used. In this case, MU
The signal component of the high-definition television signal obtained by decoding the SE signal over the recording / reproducing band of the recording medium is lost during recording, resulting in insufficient resolution (MUSE).
Recording and playback was done at the expense of the original resolution of the signal).

[0009]

Further, since the recording / reproducing band of the recording medium has no vertical or diagonal band limitation in the spatial frequency band, when the signal recorded on the recording medium is reproduced, a portion having no signal component of the MUSE signal shown in FIG. (The shaded area in the figure)
, Only the noise was reproduced, and the S / N of the reproduced signal was deteriorated.

[0010]

As a method of recording / reproducing on / from a narrow band recording medium, a MUSE signal (8.
There is also a method of recording / reproducing as it is without decoding the signal of 1 MHz band). However, with this method, the distortion of the recording / reproducing system (medium or recording / reproducing apparatus) is easily affected, and sufficient image quality cannot be obtained. The distortion of the recording / reproducing system mainly appears as the ringing of the image and the distortion of the edge portion.

[0011]

[0009]

[0012]

The problem to be solved by the present invention is to record and reproduce a high-definition television signal supplied by the MUSE system using a recording medium having a recording and reproducing band of about 12 to 13 MHz. Even in this case, what kind of means should be taken to obtain a recording / reproducing apparatus which can obtain a sufficient resolution and can improve the S / N and ringing due to the distortion of the recording medium.

[0013]

[0010]

[0014]

In order to solve the above problems, the present invention provides

[0015]

A first still picture system circuit for interpolating a signal obtained by AD-converting a MUSE signal between frames;

[0016]

A first processing of the moving image of the AD-converted signal
Video system circuit of

[0017]

A first motion detecting circuit for detecting a moving image signal of the AD-converted signal;

[0018]

The first obtained from the first motion detection circuit
A first mixing circuit that adaptively mixes the output signal of the first still image system circuit and the output signal of the first moving image system circuit according to the motion detection signal of

[0019]

A recording circuit for recording the output signal of the first mixing circuit on a recording medium;

[0020]

A reproducing circuit for reproducing a signal from a recording medium,

[0021]

A signal obtained by AD-converting the reproduced inter-frame interpolated signal and converting the sampling frequency is
A second still picture system circuit for interpolating between fields,

[0022]

A second moving picture system circuit for processing a moving picture of the sampling frequency converted signal;

[0023]

A second motion detection circuit for detecting the motion of the reproduced signal which has been subjected to interframe interpolation processing;

[0024]

The second obtained from the second motion detection circuit
A second mixing circuit for adaptively mixing the output signal of the second still image system circuit and the output signal of the second moving image system circuit according to the motion detection signal of

[0025]

At least one of the first and second moving picture circuits performs a field interpolation process to provide a recording / reproducing apparatus.

[0026]

[0022]

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The shaded area in FIG. 5 which was conventionally reproduced as a noise component is a region in which a signal component of 12 MHz or more still folds back in the middle of the decoding process of the MUSE signal. (The MUSE signal is a band-compressed signal, and the high-frequency component of the horizontal frequency band folds back toward the low-frequency component due to this band compression. The signal after the decoding process has a fold-back component. It has returned to the original high frequency side, and there is no effective signal component in the shaded area shown in FIG. 5.) Therefore, in the intermediate process of the decoding process, by recording and reproducing a signal in which a signal component of 12 MHz or more is still folded back, the hatched area in FIG. 5 is effectively utilized to solve the above-mentioned problems. The invention is the present invention.

[0028]

That is, the present invention records a signal after inter-frame interpolation processing which is an intermediate step of MUSE signal decoding processing (this signal is a signal including a folding component between fields, which is a signal of 12 MHz or more) and recorded. Inter-field interpolation processing in the remaining process of the MUSE signal decoding processing is performed at the reproduction stage of the recording signal. As a result, the present invention provides a reproduction signal (still image) having a bandwidth of 20 MHz, which is almost the entire bandwidth of the signal obtained by directly decoding the MUSE signal even if the recording / reproduction band of the recording medium is 12 to 13 MHz. System luminance signal) can be obtained.

[0029]

More specifically, according to the present invention, a signal (about 12 MHz band) at a stage where the recording side performs decoding processing up to interframe interpolation processing and is not greatly affected by distortion of a recording / reproducing system (medium or recording / reproducing apparatus). Signal). Therefore, ringing of the reproduced image and distortion of the edge portion can be significantly reduced. Further, on the reproducing side, a reproduced signal having a bandwidth of 20 MHz is obtained by utilizing the signal components of 12 MHz or more (high frequency components of the horizontal frequency band) which are present in a folded manner. As a result, the resolution of the reproduced image and the S /
N can be greatly improved.

[0030]

FIG. 1 shows the configuration of the recording system circuit of the recording / reproducing apparatus of the present invention.

[0031]

The MUSE signal input to the input terminal 1 is A
In the / D converter 2, it is re-sampled at 16.2 MHz clock. The de-emphasis circuit 3 returns the digitized MUSE signal to the emphasis process (the de-emphasis process is not required during the AM modulation). The de-emphasis processed signal is inter-frame interpolation circuit 4
It is supplied to the (first still image system circuit), the field interpolation circuit 5 (first moving image system circuit), and the motion detection circuit 6 (first motion detection circuit).

[0032]

The inter-frame interpolating circuit 4 carries out an interpolating process between the current frame signal and the signal one frame before.
It outputs a signal of 2.4 MHz rate. Since this inter-frame interpolation is a process in the time direction, it is applied to a still image.

[0033]

The field interpolating circuit 5, which is a moving picture processing circuit, carries out an interpolating process using pixels in the same field to obtain a signal of 32.4 MHz rate.

[0034]

The motion detection circuit 6 detects the difference signal in the time direction of the image to detect the motion area. Motion detection circuit 6
The mixer 7 (first mixing circuit) is controlled by the motion detection signal detected in step S3, and the still image signal interpolated between frames and the moving image signal interpolated in the field are motion adaptively mixed. To do.

[0035]

The processing up to this point is such that the color signals are line-sequentialized, time-compressed to 1/4, and multiplexed on the horizontal blanking of the Y signal (Time Compressed Integration) signal (signal of the transmission form in the MUSE system). ) Is processed as it is.

[0036]

The motion-adapted signal obtained at the mixer output is time-expanded by the TCI decoder 8 to return line-sequential signals, and the TCI decoder 8 outputs Y (luminance).
Signal and two color difference signals R-Y and B-Y signals are obtained.

[0037]

The TCI-decoded signal is converted back into an analog signal by the D / A converter 9, and is passed through the recording circuit to
It is recorded on a recording medium (not shown).

[0038]

FIG. 2 shows the frequency spectrum of the still image system Y signal recorded on the recording medium via the recording circuit. The frequency spectrum is the spectrum after interframe interpolation,
The band is expanded to 12.15 MHz by inter-frame interpolation processing. In addition, the folding back between the fields remains in the vertical and horizontal high regions (diagonal direction).

[0039]

The signal whose band has been widened up to 12.15 MHz is a signal processed up to the stage where it is not significantly affected by the distortion of the recording / reproducing system (medium or recording / reproducing apparatus). By recording this signal, the reproduced image can be reproduced. It is possible to greatly reduce the ringing and distortion of the edge part.

[0040]

Explaining this, if inter-frame interpolation processing is performed on the recording side, the effect of distortion from the recording / reproducing system on band compression is only the effect on inter-field interpolation of the reproducing system, which will be described later. The effect of this distortion is 8.
The effect is visually very small compared to the case where the MUSE signal itself in the 1 MHz band is recorded and reproduced. this is,
A signal that has been widened to 12.15 MHz by inter-frame interpolation processing is recorded, and if that signal is reproduced, re-sampling in the reproduction system will re-sample a signal in the 12 MHz band at 32.4 MHz clock. It becomes processing. Therefore, a signal in the band of about 12 MHz has a margin of 4 MHz up to the Nyquist frequency of 16.2 MHz, and the influence of aliasing on sampling is reduced. (On the other hand, when the MUSE signal itself is recorded / reproduced, there is no margin, and the first level of Nyquist must be strictly observed, which greatly affects the image.)

[0041]

A more detailed description will be given. When the MUSE signal itself is recorded / reproduced, the frequency characteristic of the signal up to recording on the recording medium and the frequency characteristic of the signal up to reproduction / A / D conversion must be as shown in FIG. 6A. . That is, since the re-sampling clock for A / D conversion is 16.2 MHz, 6 dB attenuation at the Nyquist frequency of 8.1 MHz and its attenuation characteristic is 1
It must have a 0% cosine roll-off characteristic (characteristic that satisfies Nyquist's first standard). The Nyquist frequency of 8.1 MHz is within the band of the signal to be recorded / reproduced, and it is very difficult to realize the above frequency characteristic in the analog recording / reproducing system (the characteristic of the recording medium is large). Then, the deviation from the frequency characteristic results in the generation of aliasing distortion at the time of sampling, and the distortion is M
This adversely affects interframe interpolation processing, interfield interpolation processing, and motion adaptation processing in the USE signal decoding processing process.

[0042]

On the other hand, in the case of recording / reproducing the signal inter-frame interpolated as in the present embodiment, the re-sampling in the reproducing system is performed on the signal of about 12 MHz in 32.
This is a process of re-sampling with a 4 MHz clock. In this case, the Nyquist frequency is 16.2 MHz, which is outside the band of the signal to be recorded / reproduced, and there is a margin of 4 MHz for the signal to be recorded / reproduced. Therefore, the recording / reproducing characteristics of the recording medium may be flat characteristics up to around 12 MHz as shown in FIG. 6B, and the 10% cosine roll-off characteristic may not be satisfied as the attenuation characteristic. The impulse response of the still image system having the roll-off characteristic is defined in the protocol and can be realized by the coefficient of the digital filter. The coefficient of the digital filter in the decoder is 12
It is a value obtained by convolving the coefficients of both the MHz low-pass filter 102 and the sampling frequency conversion circuit 103. The impulse response of the still image system, which has the roll-off characteristic, can be accurately realized by digital processing. Therefore, in the recording / reproducing according to the present embodiment, the adverse effect of the distortion of the recording medium (the adverse effect of the occurrence of the aliasing distortion) can be significantly reduced as compared with the recording / reproducing of the MUSE signal itself. Furthermore, in the recording / reproducing according to the present embodiment, even if the distortion of the recording medium is adversely affected, the MUSE signal itself is dispersed in a high frequency region as compared with the recording / reproducing, so that it is visually inconspicuous.

[0043]

The recording medium used in the embodiment has a recording / reproducing band of about 13 MHz. (As previously mentioned,
The MUSE signal has a flat recording / reproducing characteristic up to 12.15 MHz which is a band of a signal obtained by inter-frame interpolation processing, and of course, this signal can be recorded / reproduced without deterioration. )

[0044]

Next, a reproducing system circuit for reproducing a signal from the recording medium will be described (see FIG. 1B). In this embodiment, the signal reproduced from the recording medium on which the signal is recorded by the above method is a signal of Y, RY, BY format.

[0045]

The three signals of Y, RY and BY are digitized by the A / D converter 101 by the 32.4 MHz clock. After that, the Y signal and the C signals (color difference signals) of RY and BY are processed in different systems. The Y signal enters the process of MUSE signal decoding processing after interframe interpolation, passes through the 12 MHz low-pass filter 102, and is then supplied to the sampling frequency conversion circuit 103 and the motion detection circuit 118 (second motion detection circuit). It The sampling frequency conversion circuit 103 converts the signal of 32.4 MHz rate to 48.6 MHz rate. 48.6M
The signal having the Hz rate is separately processed into still image processing and moving image processing. In the still image processing, the changeover switch 104 is controlled by the inter-field sub-sampling control signal S, and the signal of 48.6 MHz rate is changed to 24.3 MHz.
The signal of the rate is sub-sampled, and then the inter-field interpolation circuit 105 (second still image system circuit) performs inter-field interpolation. Since the inter-field interpolation circuit 105 performs processing for interpolating from the field one field away in the time direction to the current field, its output is again 48.6M.
It becomes a signal of Hz rate. Then, the signal band is widened to the band of the final decoding process of the MUSE signal shown in FIG.

[0046]

On the other hand, in the moving image system, the in-field two-dimensional filter 106 (second moving image system circuit) suppresses an unnecessary band in the spatial frequency region, and improves the S / N of the moving image system.

[0047]

The mixer 107 mixes the still image and moving image signals.
The (second mixing circuit) performs motion adaptive mixing according to the motion detection signal obtained by the motion detection circuit 118.

[0048]

The C signal is a sampling frequency conversion circuit 11
9 from 42.4MHz signal from 32.4MHz rate signal
Converted to z-rate signal. Similarly to the Y signal, the C signal can be further widened by performing inter-field interpolation, but in the present embodiment, C is used to simplify the description.
Signal processing is simplified.

[0049]

Y and R-at a rate of 48.6 MHz
Y, BY signals are matrix, CRT gamma, 12 /
In the circuit 110 for time-expansion 11, the time-expansion circuit is once converted into R, G, B, CRT gamma correction is then applied, and matrix processing is performed again to obtain Y, Pb,
It becomes the Pr signal. The Y, Pb and Pr signals are converted into analog signals by the D / A converter 111 and output to the monitor.

[0050]

As described above, on the reproducing side, in the present embodiment, the Y signal of the still picture system is returned and is present at 12 MHz.
By effectively utilizing the above signal components (high frequency components of the horizontal frequency band), it is possible to finally output a signal having a bandwidth of 20 MHz. The bandwidth of 20 MHz is almost the entire bandwidth of the Y signal obtained by decoding the MUSE signal as it is. In this embodiment, even if a narrow band recording medium is used,
The resolution and S / N originally possessed by the USE signal can be sufficiently recorded and reproduced.

[0051]

In the above embodiment, synchronous reproduction and MUSE
The control signal required for decoding is the conventional MU.
Since it is similar to the SE decoder, its detailed description is omitted here. The control signal required after the interframe interpolation may be multiplexed with the video signal and recorded on the recording medium.

[0052]

Although the 12/11 time extension is processed by the reproducing system, there is no problem even if it is processed by the recording system, and the clock and the signal rate after the time extension are compared with the illustrated embodiment (11/12). ) It should be doubled. Also,
By providing a signal line for directly supplying the output of the TCI decoder 8 on the recording side to the low-pass filter 102 on the reproducing side and the sampling frequency conversion circuit 119 without passing through the recording medium, this device can be used as a MUSE decoder.

[0053]

Various combinations of the moving picture processing on the recording side and the moving picture processing on the reproducing side are conceivable other than the above embodiment. A combination in which the processing on the recording side and the processing on the reproducing side are replaced with those in the above embodiment, a combination of field interpolation processing in the horizontal direction on the recording side, a field interpolation processing in the vertical direction on the reproducing side, etc. may be used. Field interpolation processing may be performed on at least one of the playback side and the playback side.

[0054]

In the case of a device that does not record and reproduce at the same time, one motion detection circuit and one mixer may be provided and shared by the recording side and the reproducing side. Further, the moving image processing circuit may be omitted, and a device dedicated to still images may be used.

[0055]

Further, the recording side and the reproducing side may be separated according to the usage situation and the like to realize the recording apparatus and the reproducing apparatus.

[0056]

Next, the second embodiment will be described with reference to FIG. In this embodiment, a changeover switch 11 and a simple encoder 13 are added to the embodiment shown in FIG. 1 (hereinafter referred to as the first embodiment), and not only the MUSE signal but also the 2
A high-definition television signal of 0 MHz base band can be recorded and reproduced in a wide band.

[0057]

In the present embodiment, in order to further narrow the band of the signal recorded on the recording medium, in the first embodiment, this is performed before the D / A converter 111 on the reproducing side.
It is assumed that the / 11-hour expansion processing is performed in the preceding stage (between the TCI decoder 8) of the D / A converter 9 on the recording side. Accordingly, in the second embodiment, the frequency of the clock supplied to the D / A converter 9 and the A / D converter 101 shown in FIG. 1 is set to 29.7 MHz, and the 12 MHz low pass filter 102 is set to 11 MHz low. As a pass filter,
Sampling frequency conversion circuit 103 and changeover switch 10
4 and signal conversion, and frequency conversion in the sampling frequency conversion circuit 119 is 29.7 MHz → 22.2.
The frequency of the clock supplied to the D / A converter 111 is 44.55 MHz.

[0058]

Returning to FIG. 7, in the second embodiment, the D / A
A changeover switch 11 is provided between the converter 9 and the recording circuit 12, and the D / A is provided at one input end of the switch 11.
The output side of the converter 9 is connected, and the output side of the simple encoder 13 is connected to the other input end. The simple encoder 13 is supplied with a baseband signal (analog signal) of a high definition television signal (for example, a high definition signal),
Convert to a signal with a bandwidth of about 11 MHz. The converted signal is recorded on the recording medium by the recording circuit.

[0059]

The simple encoder 13 basically performs the inter-field sub-sampling process of the MUSE encoding process on the broadcast station side. Simple encoder 1
3 is a block 14 shown in FIG.
It becomes ~ 16. The AD converter 14 digitizes a high-definition television 20 MHz baseband signal at a 44.55 MHz clock. This signal is offset between fields by the inter-field sub-sampling circuit 15 to decimate the pixels to ½ to a 22.28 MHz rate. afterwards,
22.28MHz → 29.7MH in the sampling frequency conversion circuit 16
Perform sampling conversion to z. The filter band used for frequency conversion is the 11 MHz band. The output signal of the sampling frequency conversion circuit 16 is supplied to the recording circuit via the switch 11.

[0060]

While the filter band of the frequency conversion circuit of the MUSE encoder on the broadcasting station side corresponding to the sampling frequency conversion circuit 16 is 12 MHz band, the filter band of the sampling frequency conversion circuit 16 is 11 MHz band as described above. The reason is that the simple encoder 13 does not perform the 11 / 12-hour compression process like the broadcasting station.

[0061]

FIG. 8 shows a detailed block configuration of the simple encoder 13. At the input end, a luminance signal Y, a color signal Pb,
An analog baseband signal of Pr is input. The matrix circuit 21 converts the input signal into Mm transmission signals Ym, RY and BY. The Ym signal is processed by the low-pass filter 22 of 20 MHz and then sampled by the A / D converter 23.
Digitized at 44.55MHz.

[0062]

The digitized Y signal is output to the still image processing circuit 33, the moving image processing circuit 34, and the motion detection circuit 32.
Is supplied to each.

[0063]

In the still picture system processing circuit 33, first, the inter-field pre (previous value) filter 24 suppresses the band in the diagonal direction with respect to the incoming signal. Figure 9 shows the characteristics of this filter.
Shown in. Pixels are thinned out by the inter-field offset sub-sampling circuit 25 in the signal whose band is limited in the diagonal direction. This will be described with reference to FIG. 10, and pixels aligned at the 44.55 MHz rate shown in FIG. 10A are thinned out to pixels offset between fields shown in FIG. Offset subsampling result,
The sampling rate is 22.28 MHz, and as a result, a signal band of ½ or more of 22.28 MHz (that is, a signal band of 11.14 MHz or more) folds back to a shaded area of a solid line as shown in FIG.

[0064]

The signal with the 22.28 MHz rate is then
11 MHz by 11 MHz interpolation low-pass filter 26
Is band-limited to the original and is interpolated, resulting in the original 44.55M.
It becomes the Hz rate. Therefore, the pixel arrangement is as shown in FIG.
Return to. However, the band is limited to 11 MHz.

[0065]

The signal passed through the interpolation low-pass filter 26 is 44.55 MHz → 29.7 MHz sampling frequency conversion circuit 2
Converted to 29.7MHz rate at 7. The impulse response obtained by convolving the processes of the interpolating low-pass filter 26 and the sampling frequency conversion circuit 27 is defined by the MUSE transmission protocol.

[0066]

Next, the moving image processing circuit 34 will be described. The supplied Y signal is used in the field pre-filter 2
After the band is limited at 8, the 44.55MHz → 29.7MHz sampling frequency conversion circuit 29 converts the rate to a 29.7MHz rate.
Here, the simple encoder 13 performs processing up to the inter-field offset sub-sampling, and does not perform the inter-frame / inter-line offset sub-sampling processing in the original MUSE encoder. Therefore, the characteristic of the intra-field pre-filter 28 may be the one-dimensional filter characteristic shown in FIG.

[0067]

The characteristics of the intra-field pre-filter 28 in the vertical frequency-horizontal frequency will be compared between the simple encoder and the original MUSE encoder. An original MUSE encoder that performs inter-frame / inter-line offset sub-sampling requires a filter characteristic for suppressing an oblique direction as shown by a solid diagonal line in FIG. 11B in order to suppress aliasing due to offset sampling. On the other hand, with a simple encoder, it is not necessary to suppress aliasing due to offset sampling, so
The characteristics of the in-field pre-filter are such that the diagonal band extends as shown by the broken line in FIG.
2 in the two-dimensional spatial frequency domain compared to the USE video system
Nearly double the bandwidth can be obtained.

[0068]

The moving picture system signal is obtained at the output of the sampling frequency conversion circuit 29, and the still picture system signal is obtained at the output of the sampling frequency conversion circuit 27. The signals of the still image system and the moving image system are mixed in pixel unit by the mixer 30 according to the motion detection signal obtained by the motion detection circuit 12.

[0069]

The 29.7 MHz signal obtained at the output of the mixer 30 is converted into an analog signal by the D / A converter 31, supplied to the recording circuit, and recorded on the recording medium.

[0070]

The band of the signal output from the simple encoder 13 is a band of 11 MHz in the still picture system as shown in FIG. 9 and about 14 as shown in FIG. 11 (b) in the moving picture system.
It becomes the band of MHz. FIG. 12 is a re-description of the bands of the still image system and the moving image system. Bandwidth of recording medium is 1
Since it is 2 to 13 MHz, the band is slightly limited in the recording / reproducing system for the moving image system, but can be completely recorded / reproducing in the recording / reproducing system for the still image system.

[0071]

The output of the simple encoder 13 is
The signal obtained by subjecting the baseband signal to the inter-field offset sub-sampling process is a signal equivalent to the signal obtained by subjecting the MUSE signal, which is the output of the recording system circuit shown in FIG.

[0072]

Therefore, for the still picture system, the field reproduced from the recording medium by the reproduction circuit (not shown) is inter-field interpolated by the circuit of the reproduction system shown in FIG. 1B. A signal of about 20 MHz band similar to the original signal is obtained. On the other hand, as for the moving image system, the band is slightly limited in the recording / reproducing system as described above.
As compared with the moving image system of the system, a band that is nearly double in the two-dimensional spatial frequency domain can be obtained, so that abundant information of the baseband signal can be sufficiently recorded and reproduced.

[0073]

Although the above description has been focused on the Y signal, the C signal is output by the outputs BY and R of the matrix circuit 21 shown in FIG.
-Y may be recorded and reproduced by the circuit of the reproduction system shown in FIG.

[0074]

The present embodiment has the above contents, and the changeover switch 11 shown in FIG. 7 switches between the signal inter-frame interpolated in the MUSE decoding section and the output signal of the simple encoder 13 so that only the MUSE signal is obtained. Not only that, it is possible to record and reproduce high-definition television baseband signals while maintaining the band of 20 MHz.

[0075]

Although the MUSE encoding section, the recording / reproducing circuit, and the simple encoder are integrated in this embodiment, each section may be formed separately as necessary.
When the MUSE encoding unit is provided separately, as shown in FIG. 13, a changeover switch 120 is provided between the TCI decoder 8 and the low-pass filter 102 in the MUSE encoding unit, and the TCI decoder 8 and the sampling frequency are provided. Changeover switch 1 between conversion circuit 119
21 and 122 may be provided so that a path that passes through the external recording / reproducing circuit and a path that does not pass can be selected.

[0076]

Further, the recording side and the reproducing side of the second embodiment may be separated according to the use situation and realized as a recording device and a reproducing device.

[0077]

[0072]

[0078]

As described above, the present invention has the following effects.

[0079]

(A) In the recording / reproducing apparatus according to the first aspect, the MUSE signal is decoded up to the inter-frame interpolation processing on the recording side and is not greatly affected by the distortion of the recording / reproducing system (medium or recording / reproducing apparatus). It is recorded on the recording medium as a step signal (a signal in the band of about 12 MHz). Therefore, the recording / reproducing apparatus can significantly reduce the ringing of the reproduced image and the distortion of the edge portion, which are caused by the distortion of the recording / reproducing system, as compared with the conventional example.

[0080]

Further, since the signal component of 12 MHz or more (the high frequency component of the horizontal frequency band) is folded back to the low frequency component side in the recording signal, the present recording / reproducing apparatus:
On the reproducing side, a still image type luminance signal having a bandwidth of 20 MHz can be reproduced by utilizing the signal components of 12 MHz or more that are present in a folded manner. Therefore, this recording / reproducing apparatus has a narrow recording / reproducing band (for example, 12 to 13 MHz).
Even if a recording medium is used, it is possible to obtain a reproduced image having a high resolution and a high S / N that are comparable to those obtained by directly decoding the MUSE signal.

[0081]

(B) A recording apparatus according to a second aspect is an apparatus having a circuit on the recording side of the recording / reproducing apparatus according to the first aspect, wherein the MUSE signal is decoded up to interframe interpolation processing, and a recording / reproducing system is provided. Signals at a stage where they are not significantly affected by distortion of the medium or recording / reproducing device (signals of about 12 MHz band)
Can be recorded on a recording medium. Further, the recording signal is a signal in which a signal component of 12 MHz or more (a high frequency component of the horizontal frequency band) exists while folding back to the low frequency component side. Therefore, by using this recording device, even when recording is performed on a recording medium having a narrow recording / reproducing band (for example, about 12 to 13 MHz), if a signal is reproduced from the recording medium, ringing and distortion of the edge portion are small, Also,
It is possible to obtain a reproduced image having the same high resolution and high S / N as that obtained by decoding the MUSE signal.

[0082]

(C) The reproducing apparatus according to claim 3 is an apparatus having a circuit on the reproducing side of the recording and reproducing apparatus according to claim 1, and the recording and reproducing apparatus according to claim 1 and the recording according to claim 2 By reproducing the signal from the recording medium recorded by the device, the ringing and the distortion of the edge part are small, and the MUS
It is possible to obtain a reproduced image having the same high resolution and high S / N as that obtained by decoding the E signal.

[0083]

(D) In the recording / reproducing method according to the fourth aspect, ringing or recording is performed even when recording is performed on a recording medium having a narrow recording / reproducing band (for example, about 12 to 13 MHz) for the same reason as described in (a) above. Distortion at the edge is small, and M
It is possible to obtain a reproduced still image having the same high resolution and high S / N as that obtained by decoding the USE signal.

[0084]

(E) In the recording / reproducing method according to the fifth aspect, in addition to the effect of the fourth aspect, the recording / reproducing of the moving image of the MUSE signal can be performed.

[0085]

(F) In addition to the effect of the recording / reproducing apparatus according to the first aspect, the recording / reproducing apparatus according to the sixth aspect includes a recording / reproducing medium and a recording / reproducing circuit having a narrow recording / reproducing band (for example, about 12 to 13 MHz). By using this, not only the still picture system signal of the MUSE signal but also the still picture system signal of the base band signal of the high definition television can be recorded and reproduced while maintaining the band of 20 MHz. Further, since the moving image system signal of the base band signal of the high definition television can be recorded and reproduced with a band nearly twice in the two-dimensional spatial frequency region as compared with the moving image system signal of the MUSE signal, it can be abundant in the base band signal. Information can be recorded and reproduced sufficiently.

[0086]

(G) A recording device according to a seventh aspect is a device having a circuit on the recording side of the recording and reproducing device according to the sixth aspect, and has a narrow recording and reproducing band (for example, about 12 to 13 MHz), a recording and reproducing medium, By using the recording circuit, not only the MUSE signal having a band of 20 MHz, but also the baseband signal of a high-definition television can be recorded with high quality without signal deterioration. In particular, a high-definition television baseband video signal can be recorded with a band nearly twice as large in a two-dimensional spatial frequency region as a MUSE signal video signal, so that the rich information of the baseband signal can be recorded. Can be recorded sufficiently.

[0087]

(H) The reproducing apparatus according to claim 8 is an apparatus having a circuit on the reproducing side of the recording and reproducing apparatus according to claim 6, and the recording and reproducing apparatus according to claim 6 and the recording according to claim 7. By reproducing the signal from the recording medium recorded by the device, the high resolution and high S / of the original signal in the 20 MHz band can be obtained.
It can be reproduced without deteriorating with N.

[0088]

(L) In the recording / reproducing method according to claim 9, a recording / reproducing medium and a recording / reproducing circuit having a narrow recording / reproducing band (for example, about 12 to 13 MHz) are used, and not only the still picture system signal of the MUSE signal but It is possible to record and reproduce a still image system signal of a base band signal of a high definition television while maintaining the band of 20 MHz. Further, since the moving image system signal of the base band signal of the high definition television can be recorded and reproduced with a band nearly twice in the two-dimensional spatial frequency region as compared with the moving image system signal of the MUSE signal, it can be abundant in the base band signal. Information can be recorded and reproduced sufficiently.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an embodiment (first embodiment) of a recording / reproducing apparatus of the present invention.

FIG. 2 is a diagram showing a frequency spectrum after inter-frame interpolation.

FIG. 3 is a diagram for explaining a conventional device for recording a MUSE signal.

FIG. 4 is a diagram for explaining a device when reproducing a conventional MUSE signal.

FIG. 5 is a diagram showing a spectrum after MUSE decoding processing and a recording / reproducing band of a recording medium.

FIG. 6 is a diagram showing a relationship between frequency characteristics of a recording medium and a resampling clock.

FIG. 7 is a diagram showing a configuration of a main part of a second embodiment of a recording / reproducing apparatus of the present invention.

FIG. 8 is a diagram showing a configuration of a simple encoder according to a second embodiment.

FIG. 9 is a diagram showing a recording / reproducing band and an inter-field pre-filter characteristic of a recording / reproducing circuit in a two-dimensional spatial frequency domain.

FIG. 10 is an explanatory diagram of inter-field offset subsampling.

FIG. 11 is a video encoder pre-filter and MU of a simple encoder.
It is a figure for demonstrating the difference of the intra-field prefilter of SE encoder.

FIG. 12 is a diagram showing a spectrum of a recording signal.

FIG. 13 is a diagram showing a configuration when a MUSE decoding unit is provided separately.

[Explanation of symbols]

2 A / D converter 3 De-emphasis circuit 4 Interframe interpolating circuit (first still picture system circuit) 5 Field interpolating circuit (first moving picture system circuit) 6 Motion detection circuit (first motion detection circuit) 7 Mixer (First Mixing Circuit) 105 Interfield Interpolation Circuit (Second Still Picture System Circuit) 106 Two-Dimensional In-Field Filter (Second Moving Picture System Circuit) 107 Mixer (Second Mixing Circuit) 118 Motion detection circuit (second motion detection circuit)

Claims (9)

[Claims] 1. A first still picture system circuit for interpolating a signal obtained by AD-converting a MUSE signal between frames, a first motion picture system circuit for processing a moving picture of the AD-converted signal, and the AD-converted signal. A first motion detection circuit for detecting the moving picture signal of the first motion detection circuit, and an output signal of the first still image system circuit and the first motion detection circuit according to the first motion detection signal obtained from the first motion detection circuit. A first mixing circuit that adaptively mixes an output signal of a video system circuit; a recording circuit that records the output signal of the first mixing circuit in a recording medium; a reproducing circuit that reproduces a signal from the recording medium; A second still image system circuit that interpolates a signal obtained by AD-converting the inter-frame interpolated signal that has been subjected to the inter-frame interpolation processing, and a second moving image that performs video processing of the sampling frequency-converted signal. System circuit, before A second motion detection circuit that detects the motion of the reproduced inter-frame interpolation processed signal, and the second still image according to the second motion detection signal obtained from the second motion detection circuit. A second mixing circuit that adaptively mixes the output signal of the system circuit and the output signal of the second video system circuit is provided, and at least one of the first and second video system circuits is field-interpolated. A recording / reproducing apparatus characterized by performing processing. 2. A still picture system circuit for interpolating a signal obtained by AD-converting a MUSE signal between frames, a moving picture system circuit for processing a moving picture of the AD-converted signal, and detecting a moving picture signal of the AD-converted signal. A motion detection circuit and, according to the motion detection signal obtained from the motion detection circuit,
A recording apparatus comprising: a mixing circuit for adaptively mixing the output signal of the still image system circuit and the output signal of the moving image system circuit; and a recording circuit for recording the output signal of the mixing circuit on a recording medium. . 3. A reproducing circuit for reproducing a signal from a recording medium, and a still picture system circuit for inter-field interpolating a signal obtained by AD-converting the reproduced inter-frame interpolated signal and converting the sampling frequency. A moving picture system circuit for moving picture processing the signal whose sampling frequency has been converted, a motion detection circuit for detecting the movement of the reproduced inter-frame interpolation processed signal, and a motion detection signal obtained from the movement detection circuit hand,
A reproducing apparatus provided with a mixing circuit for adaptively mixing an output signal of the still picture system circuit and an output signal of the moving picture system circuit. 4. A recording system signal processing step of decoding a MUSE signal up to interframe interpolation processing and recording it on a recording medium, and an interfield interpolation processing in a MUSE signal decoding processing for a signal reproduced from the recording medium. And a reproducing system signal processing step for performing the recording and reproducing method. 5. The MUSE signal is decoded up to the inter-frame interpolation process, the first moving image process is performed on the MUSE signal, and the decoded signal and the first moving image processed signal are subjected to motion adaptive mixing. And a recording system signal processing step of recording on a recording medium, and inter-field interpolation processing in MUSE signal decoding processing is performed on the signal reproduced from the recording medium, and a second signal is reproduced on the signal reproduced from the recording medium. A recording / reproducing method, comprising: a reproduction system signal processing step of performing moving image processing and performing motion adaptive mixing of the signal subjected to inter-field interpolation processing and the second signal subjected to the moving image processing. 6. A first still picture system circuit for interpolating a first signal obtained by AD-converting a MUSE signal between frames, and a first moving picture system circuit for processing a moving picture of the first signal. A first motion detection circuit for detecting a moving image signal of the first signal, and an output of the first still image system circuit according to a first motion detection signal obtained from the first motion detection circuit. A first mixing circuit that adaptively mixes a signal and the output signal of the first video system circuit, and a second signal obtained by AD-converting a baseband signal of a high-definition television. A third still image system circuit that performs sampling processing to obtain a signal equivalent to that after interframe interpolation processing, and a third moving image system circuit that performs moving image processing of the second signal using an in-field prefilter for one-dimensional processing. And detecting a moving image signal of the second signal, And the output signal of the third still image system circuit and the output signal of the third moving image system circuit according to the third motion detection signal obtained from the third motion detection circuit. A third mixing circuit that adaptively mixes, a switching circuit that selects and outputs the output signal of the first mixing circuit and the output signal of the third mixing circuit, and the output signal of the switching circuit to a recording medium. A recording circuit for recording, a reproducing circuit for reproducing a signal from a recording medium, and a sampling frequency conversion by AD-converting a reproduced inter-frame interpolated signal or a reproduced inter-frame interpolated signal. A second still picture system circuit that interpolates the generated signal between fields, a second moving picture system circuit that processes the sampling frequency converted signal as a moving picture, and the reproduced signal that has been subjected to interframe interpolation processing or A second motion detection circuit that detects a motion of a signal that is equivalent to the generated interframe interpolation processing, and the second motion detection signal that is obtained from the second motion detection circuit. A second mixing circuit for adaptively mixing the output signal of the still image system circuit and the output signal of the second moving image system circuit is provided, and at least one of the first and second moving image system circuits is in the field. A recording / reproducing apparatus characterized by performing an interpolation process. 7. A first still picture system circuit for interpolating a first signal obtained by AD-converting a MUSE signal between frames, and a first moving picture system circuit for processing the first signal as a moving picture. A first motion detection circuit for detecting a moving image signal of the first signal, and an output of the first still image system circuit according to a first motion detection signal obtained from the first motion detection circuit. A first mixing circuit that adaptively mixes a signal and the output signal of the first video system circuit, and a second signal obtained by AD-converting a baseband signal of a high-definition television. A third still image system circuit that performs sampling processing to obtain a signal equivalent to that after interframe interpolation processing, and a third moving image system circuit that performs moving image processing of the second signal using an in-field prefilter for one-dimensional processing. And detecting a moving image signal of the second signal, And the output signal of the third still image system circuit and the output signal of the third moving image system circuit according to the third motion detection signal obtained from the third motion detection circuit. A third mixing circuit that adaptively mixes, a switching circuit that selects and outputs the output signal of the first mixing circuit and the output signal of the third mixing circuit, and the output signal of the switching circuit to a recording medium. A recording device provided with a recording circuit for recording. 8. A reproducing circuit for reproducing a signal from a recording medium, and a reproduced inter-frame interpolated signal or a reproduced inter-frame interpolated signal which has been subjected to AD conversion and sampling frequency conversion. A still picture system circuit for interpolating a signal between fields; a moving picture system circuit for moving picture processing of the signal whose sampling frequency has been converted; a reproduced interframe interpolation processed signal or the reproduced interframe interpolation A motion detection circuit that detects the motion of a signal equivalent to the processed signal, according to the motion detection signal obtained from the motion detection circuit,
A reproducing apparatus provided with a mixing circuit for adaptively mixing an output signal of the still picture system circuit and an output signal of the moving picture system circuit. 9. A MUSE signal is decoded up to interframe interpolation processing, a first moving image processing is performed on the MUSE signal, and the decoded signal and the first moving image processed signal are subjected to motion adaptive mixing. The first recording system signal processing step and the high-definition television baseband signal are made into a signal equivalent to the one that has been subjected to the inter-frame interpolation processing by performing the offset sub-sampling processing between fields, Second recording system signal processing for performing second adaptive moving image processing by using an in-field pre-filter for dimensional processing, and performing motion adaptive mixing of the signal subjected to the offset sub-sampling processing between the fields and the second moving image processed signal The process, the signal obtained in the first recording system signal processing process, and the signal obtained in the second recording system signal processing process. A recording process of selecting one of them and recording it on a recording medium, performing inter-field interpolation processing in a MUSE signal decoding process on a signal reproduced from the recording medium, and performing a third process on a signal reproduced from the recording medium. And a reproducing system signal processing step of performing motion adaptive mixing of the inter-field interpolation processed signal and the third video processed signal.