JPH07264624A - Digital television signal processor - Google Patents

Abstract

PURPOSE:To obtain excellent picture quality only when an input signal is a nonstandard signal which do not meet the specifications of the NTSC system by automatically detecting whether or not the input signal is a regular standard signal or nonstandard signal and switching one or both of a signal processing system and a clock. CONSTITUTION:When the input signal is the standard signal, the output of a frequency divider 126 and the output of a frequency divider 135 are synchronized with each other and the output of the frequency divider 126 is included in the output of the frequency divider 135. A comparator 136 confirm their coincidence by ANDing the both and decides that the input signal is the standard signal. If, however, the input signal is the nonstandard signal, the output of the frequency divider 126 is not included in the output of the frequency divider 135. the comparator 136 detects their anticoincidence and decides that the input signal is the nonstandard signal. Then a motion adaptive time space luminance chromaticity separating circuit is switched to processing in space by performing switching so that normal signal processing is performed for the standard signal and a voltage controlled oscillator 130 based upon a horizontal synchronizing signal is utilized for the nonstandard signal.

Description

Detailed Description of the Invention [0001] BACKGROUND OF THE INVENTION The present invention relates to a digital television.
Signal processing device, especially N generated by VTR or the like.
Optimal for non-standard signals that do not meet TSC specifications
Performs signal processing including synchronization processing that is necessary to perform various types of processing.
The present invention relates to a digital television signal processing device. [0002] 2. Description of the Related Art In conventional television receivers, color signals
Is caused by being frequency-multiplexed with the luminance signal.
Scalar, dot crawl, and interlaced scanning
Image quality due to line flicker, scanning line interference, etc.
It is known that aging will occur. Such image quality deterioration
In order to eliminate factors and improve image quality, semiconductor memory
And digital signal processing technology
Frames that use relationships (frame correlation, field correlation)
Y / C separation by comb filter (for luminance and chromaticity)
Distance), scanning line density doubled by inter-field interpolation, order
Considering the introduction of time axis processing technology such as next scan conversion
(JP-A-58-115995, JP-A-58-793)
79). However, these image quality improving means are well known.
Only for still images with strong frame and field correlation
However, it is effective for moving images.
It will cause harm. Therefore, the difference between frames
When the motion of the image is detected by
Is a frame comb filter, inter-field interpolation
On the other hand, the processing on the time axis, on the other hand, when it is determined that the moving image,
So-called motion adaptation, switching to spatial processing in the field
It is known to introduce shape processing and aim for practical use
(JP-A-59-45770). [0003] SUMMARY OF THE INVENTION The above-mentioned technique is related to color sub-conveyance.
Wave frequency f_SC, Horizontal scanning frequency f_H, Vertical scanning frequency f_V
However, there is a
Effectiveness of vision signals (hereinafter referred to as standard signals)
The result can be expected, but it is a home VTR or personal computer.
F like data_SC, F_H, F_VTo the specified frequency relationship
No television signal (hereinafter referred to as non-standard signal)
There is a problem that it is not possible to bring out the effect
It was. For example, in the case of the NTSC system, f_SCWhen
f_HIs f_SC= (455/2) f_H      ───── (1) Is also f_HAnd f_VBetween           f_H = (525/2) f_V = (262 + 1/2) f_V─ (2) The relationship is defined. In equation (2), the scan line is
It shows that it is talising, next to the current field.
Considering the pixels on two scanning lines that meet each other, it is exactly in the middle.
Corresponds to the pixel of the scanning line in the previous field. on the other hand,
From equation (1) and equation (2)           f_SC= (119437 + 1/2) f_V/ 2 ────── (3) Is obtained, but this is because the phase of the color subcarrier is one frame period
Between (frequency f_V/ 2) It is possible to have opposite phases between distant signals.
Show. In this way, the above relationship holds for standard signals.
Frame comb processing and inter-field interpolation
It becomes Noh. However, the frequency f_SC, F_H, F_VIs the above
For non-standard signals that do not satisfy equations (1) and (2),
Pixel correspondence between fields, color subcarrier inversion between frames
Since the relationship is not established, inter-field scanning line interpolation and
Accurate separation of luminance and chrominance signals by frame comb
become unable. Therefore, if it is judged as a still image,
, The image quality is significantly deteriorated by the above processing.
Thus, in the prior art, standard / non-standard signals
Appropriate for non-standard signals
It was difficult to perform such a treatment. On the other hand, in order to perform the scanning line interpolation processing,
Horizontal scanning frequency f of force signal_HTwice as much water based on
Flat scan frequency 2f_HPlay, this will display
It is necessary to drive the deflection circuit on the side (JP-A-57-15).
2279, JP-A-58-79379). Traditionally, this
In order to show it, after extracting the synchronization signal from the input signal, the PLL
2f depending on the circuit_HIs generated and used as a reference for signal processing,
Furthermore, this 2f_HThe AFC circuit on the deflection side
It was common to replay the issue. In this case, the input signal
From the perspective, two first and second PLLs connected in cascade
2f through the circuit_HWill be playing a sync signal
Therefore, the above-mentioned home-use VTR that contains a lot of jitter and skew
For non-standard signals such as, stability of reproduced sync signal
There was a problem that was bad. That is, the input signal is skewed.
-(Step-like phase change) exists, the first PL
L responds oscillatory to follow it. Then the second
The PLL further swings to follow the output of the first PLL.
Since it operates dynamically, it perfectly follows the phase change of the input.
The delay time until becomes large. It also happens irregularly
Considering the jitter, each PLL for each jitter
Operates as described above, so jitter and its response
Depending on the situation of the answer, rather to increase the shaking
Also becomes. As described above, in the related art, the home VT
Stable sync signal reproduced against non-standard signal such as R
There was also the problem of poor degree. The object of the present invention is also good for non-standard signals.
This is a signal processing unit that performs signal processing including synchronization processing that can obtain good image quality.
A digital television signal processing device is provided. [0008] [Means for Solving the Problems]
Therefore, in the present invention, the synchronizing signal is input from the input television signal.
Separate the first pulse based on the separated sync signal
Means for generating and included in the input television signal
Generate a second pulse synchronized with the color burst signal
Means and a predetermined number of the first and second pulses, respectively.
Of the first and second frequency dividers, and the first and second frequency dividers
Equipped with comparison means for comparing outputs,
Signal is a standard signal or a non-standard signal, and
Optimal processing based on the input television signal based on
To do. Furthermore, in order to ensure the detection operation, the optical
Standard signal like still mode of Deodisc player
For non-standard signals very close to
Disturbance detection for detecting disturbance of control voltage for burst reproduction
Means is provided, which also determines whether standard signals or non-standard signals
I made a decision. On the other hand, regarding the reproduction of the horizontal synchronizing signal, 1
I tried to reproduce this with one PLL. That is,
Synchronous separation output and divided flyback pulse
Control the voltage controlled oscillator by direct phase comparison and
By dividing the frequency by several times, the sync signal with double horizontal frequency is regenerated.
Alive Also, the output of the voltage controlled oscillator is a non-standard signal.
Also used as an optimal signal processing clock for processing
Be done. The above objects are achieved by the above means.
It [0012] The first frequency divider has a sync separation output f_HM minutes
(M = 1, 2, ...), while the second divider is empty
-Burst signal f_SCIs divided by 455m / 2 and compared with
Compares the output cycles of both. Input television
If the signal is a standard signal, the formula (1) holds, so compare
The means outputs a coincidence output and discriminates it as a standard signal. On the other hand, enter
If the power television signal is a non-standard signal, then equation (1)
Is not established, the comparison means outputs a mismatch output and
Judge as a signal. Next, the optical video disc player
In color mode, the color sub-carrier of the output video signal
The wave phases are in-phase between frames. Therefore, the inverse correlation
Frame comb filters that use ties can be used
It cannot be done and it becomes a nonstandard signal. In this case, the color subcarrier is one in one frame.
Color burst at that point because it becomes discontinuous
The control voltage for reproduction is disturbed. Therefore, the control voltage
The disturbance detection means of the
If it exceeds the threshold value, it is judged as a non-standard signal. Based on the above detection results, the signal processing circuit
For the reasons described below, the processing clock should be
Is usually used as a clock based on color burst
Signal processing, while for non-standard signals, horizontal
The output of the voltage controlled oscillator based on the synchronization signal
To change the time, and also the motion adaptive spatiotemporal luminance chromaticity separation circuit
Switch to processing in space. Further, the voltage controlled oscillator and the frequency divider and
And the phase comparison means constitute a PLL circuit, and the input horizontal
The period signal has a frequency twice as high as that of the direct reference signal.
Create a lieback pulse and drive the deflection system directly. Since
Due to the above, optimal processing can be performed even for non-standard signals, which is good
It is possible to provide excellent image quality. [0017] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Digital television signals of the present invention
First embodiment of signal and synchronization processing circuit by processing device
Will be described with reference to FIG. Also, all explanations below are N
The TSC method is used as an example. In FIG. 1, 101 is a video signal input terminal.
Child, 102 is a line comb filter, 103 and 104 are
A switch, 105 is a band pass filter (BPF), 10
6 is a color demodulation circuit, and 107 and 108 are luminance signals.
, A / D converter for color signals, 109 is motion adaptive brightness
(Y) Separation circuit (frame comb filter and line comb
Shape filter), 110 is a motion adaptive color (C) separation circuit (same as
Top), 111 and 112 are switches, 113 is for luminance signal
Noise reducer, 114 is a noise reducer for color signals
And 115, a motion signal adaptive scanning line interpolation circuit for luminance signal, 11
6 is a color signal scanning line interpolation circuit, 117 and 118 are respectively
And a D / A converter for luminance signals and chrominance signals, and 119 for RG
B conversion circuit, 120 is a cathode ray tube, 121 is a burst signal
No. extraction circuit, 122 is a phase comparator, and 123 is a low-pass filter.
Filter (LPF), 124 is a voltage controlled oscillator, 125,
126 is a frequency divider, 127 is a sync separation circuit, and 128 is a phase
Comparator, 129 is 2PF, 130 is voltage controlled oscillator, 1
31 is a frequency divider, 132 is a horizontal excitation / output circuit, and 133 is
Flyback transformer, 134 and 135 are frequency dividers, 13
6 is a period comparator, 137 is an integrator, 138 is a switch,
Reference numeral 139 is a frequency divider. 140 is a pretreatment unit, 141 is water
A flat sync reproducing unit, 142 is a control voltage disturbance detection circuit, 14
3 is an OR circuit. First, the outline of the operation of the signal processing system will be described.
Bell. When a standard signal is input, switches 103 and 1
04, 111, 112, 138 are closed on the opposite side of the drawing.
It The luminance signal A / D converter 107 receives the input signal.
It is entered as is. On the other hand, for color signals, BPF1
In 05, only the color signal band is extracted, and the color demodulation circuit 10
A color difference signal is obtained at 6. Color signal A / D converter 10
8 receives this and converts it into a digital signal. Less than
For the luminance signal, the motion-adaptive spatiotemporal luminance separation circuit 1
09, luminance signal without crosstalk from color signal
And reduce noise by the noise reducer 113
Then, the motion adaptive spatiotemporal scanning line interpolation circuit 115 scans the scanning lines.
Interpolation is performed and the horizontal cycle is reduced to 1/2 by the D / A converter 117.
The luminance signal of the specified double speed is obtained. Also, regarding color signals
Is the luminance signal in the motion-adaptive color separation circuit 110.
Obtains a color signal without crosstalk from the noise reducer
The noise is reduced by 114, and the scanning line interpolation circuit 116
Scan line is interpolated by, and horizontal cycle is performed by D / A converter 118.
Outputs a double speed color signal in which is reduced to 1/2. D / A
The double speed luminance signal / color difference signal output of the converters 117 and 118 is
RGB signals are converted into RGB signals by the RGB conversion circuit 119, and
The untube 120 is driven. Next, the operation when a non-standard signal is input
I will describe. If a non-standard signal is input, the switch
The switches 103, 104, 111, 112 and 138 are as shown in the figure.
Close. First, the input video signal is a spatial processing line.
The comb filter 102 separates the luminance signal and the chrominance signal.
The color signal passes through the BPF 105 and the color demodulation circuit 106.
Result in a color difference signal. And the luminance signal obtained in this way
The color difference signals are output by the A / D converters 107 and 108, respectively.
Are converted to digital signals. A / D converter 107
The outputs of and 108 are the Y separation and C separation circuits 109 in the figure.
Jump 110 and noise reducer 11
It is input to 3,114, and the noise in the low frequency range is reduced. Below, run
The scanning lines are interpolated by the contour line interpolation circuits 115 and 116.
And D / A converters 117 and 118, RGB conversion circuit 11
The cathode ray tube 120 is driven via 9. Next, generation of a clock used for signal processing
Describe the method. In this example, included in the input signal
Clock created based on the color burst signal
With reference to the signal and the horizontal sync signal included in the input signal
Prepare the generated clock signal and compare it with the standard signal.
The former is used, and the latter is used for non-standard signals. This
Here, the former is the burst lock clock and the latter is the line lock clock.
Let's call it the clock clock. Now input video signal
Burst signal extraction circuit 121 to color burst
Signal (frequency f_SC) Is extracted. Voltage controlled oscillator 124
Is 8f_SCIt oscillates at the frequency
The frequency is divided by 8 and the phase comparator 122 outputs a color burst.
The phase of the signal is compared and the error voltage is supplied. one
On the other hand, the sync separation circuit 127 synchronizes with the input video signal.
The signal is extracted and input to the phase comparator 128. Voltage control
The oscillator 130 is still 8f_SCAnd oscillate at
The frequency divider 131 to the 910 frequency divider and the frequency divider 134.
Divided by 2 (total of 1820 divided) and sync separation output and phase
Compare and receive the error voltage. Voltage controlled oscillator
The outputs of 124 and 130 are burst lock clocks, respectively.
It becomes a lock and a line lock clock. This clock
The D / A converters 117 and 118 are directly connected to the frequency divider 13
The A / D converters 107 and 108 are driven via 9. The standard signal and the non-standard signal are described below.
The reason for switching the signal processing system and the clock
Bell. Figure 2 shows (a) for standard and non-standard signals.
Error burst signal, (b) horizontal sync signal, (c) verse
Tlock clock, (d) Line lock clock
It is a thing. First, for the standard signal, one horizontal synchronization period
Color burst signal f between_SCExists for 455/2 cycles
Because ((a) figure) 4f_SCBurst rock black
Clock and line lock clock are 9 in one horizontal cycle period.
There are 10 cycles (Figs. (C) and (d)). Comb shape
The filter is one frame cycle or one line cycle.
Luminance and chrominance signals are calculated by performing calculations between signals that are separated by a fixed period.
Is to be separated. This figure shows which clock
Even if you use
However, since the luminance signal is in phase, the
If the sum of the isolated signals is taken, it is the luminance signal, if the difference is taken, it is the color signal
Can be obtained. Next, regarding scan line interpolation,
Scan lines in the current field between scan lines in the current field
(For example, the previous scan line) or the scan line of the previous field
It is not necessary to set any black
, The information of the signals separated by the number of clocks
Since the report corresponds exactly, the scan line is correctly interpolated.
be able to. For the noise reducer,
Noise is reduced by calculating the corresponding pixels between frames.
However, even if any clock is used,
Information of signals separated by a fixed number of clocks corresponds accurately
You can get a good operation with. Next, a non-standard signal input will be described.
It The non-standard signal is 1 color burst signal as shown.
There are no 455/2 cycles in the horizontal synchronization period ((a)
Figure). Currently, there are more than 455/2 cycles in one horizontal synchronization period
It is supposed to exist. Therefore, in this case, the burst block
There are more than 910 clock cycles in one horizontal sync period.
(Figure (c)), while the line lock clock is just
There are 910 cycles (Fig. (D)). However, with the burst lock clock
Considering signals 910 cycles apart, the color bar
The phase of the strike signal is inverted. Therefore, the high frequency range of brightness is
If the minute is small, the
No. can be extracted, and also input this signal
You can subtract it from the video signal to get the luminance signal
It When the luminance signal has high frequency components, the sum of the above
Depending on the pixel of the luminance signal is calculated by
Since this component is missing and leaks into the color signal,
The pixel difference is small when viewed at, so the effect is minor.
However, if you use a frame comb filter,
The pixel difference between rams is the accumulation of that between scan lines.
Therefore, the error is large and the separation performance of the comb filter is very poor.
Turn into. Therefore, the frame comb filter cannot be used.
Yes. On the other hand, for scanning line interpolation, a luminance signal,
And fitting scanning lines to demodulated color signals
However, since the scanning is performed using the horizontal synchronization signal as a reference,
The clock used for scanning line interpolation is also based on the horizontal sync signal.
It is better to make the pixels correspond. Therefore, scan line compensation
A line lock clock should be used in between. this
In the case, as shown in FIG.
Burst signal exists for more than 455/2 cycles
Therefore, there is a difference between the luminance signal and the color signal near the end of horizontal scanning.
However, this is a property originally present in the input signal.
Therefore, it is not a disturbance that occurs on the receiving side. As for the noise reducer,
Since pixel correspondence between frames is important,
The clock is good. Line lock clock feel
The same applies to the vertical sync signal when viewed in frame or frame units.
This is because it is expected. As described above, the clock used is
For standard signals, the burst lock clock and
Either in-lock clock or non-standard
For the No. signal, the comb filter has a burst lock clock.
A line lock clock is suitable for clock and scan line interpolation. Was
Burst lock clock and line lock clock
By comparison, the former is a crystal oscillator and the latter is an LC filter.
Since it is often configured using an oscillator
Comparing N (clock jitter, etc.), the former is superior.
Has been. Therefore, for standard signals, burst burst
It is possible to obtain better characteristics by using a clock clock.
Wear. Burst lock is applied to non-standard signals.
I said that the clock is good, but this is only 63.5 microseconds.
It is the calculation of the signal where the element is far away.
And comb with a normal analog delay line (glass delay line)
Shape filters are equivalent to this. Therefore, in this embodiment
Burst lock clock, scan for comb filter
Two clocks called line lock clocks for line interpolation
To avoid the use of
A delay line is provided. Next, a method of detecting a standard signal or a non-standard signal
I will describe. The first means of this detection is as described above.
Burst-locked clock generated by
The pulse related to the inlock clock is used. Well
And as a pulse related to the burst lock clock.
As shown in 1, the output of the frequency divider 125 is used. This out
The frequency of force is f_SCHowever, the frequency divider 126
For example, if the frequency is divided by 455/525/4, formulas (1) and (2)
The pulse corresponding to the vertical frequency can be obtained by
(For the division of 455/525/4, 4f_SCNa
The clock signal can be obtained by dividing the clock signal by 455/525.
I). On the other hand, the line lock clock related
The output of the frequency divider 134 is used as a rule. Of this output
Frequency is f_HTherefore, the frequency divider 135
If the frequency is divided by 525/2, the vertical frequency is still supported.
The pulse can be obtained. For these two pulses,
For example, as shown in FIG.
When 126 is reset, the output of each frequency divider is
It becomes as shown in FIG. That is, in FIG.
The frequency divider 135 has a reset output shown in FIG.
Rising before this reset pulse and after
Generate an output with a predetermined width. The former lyce
Reset pulse for the frequency divider 126
The frequency divider 126 divides the frequency based on this
The output of the divider 126 will be the input signal.
Whether the signal is a standard signal or a nonstandard signal, as described below.
It occurs at different times. That is, if the input signal is a standard signal,
Since equations (1) and (2) are satisfied, as shown in FIG.
The output of the frequency divider 126 and the reset output of the frequency divider 135
Have almost the same timing. Therefore, the frequency divider 12
The 6 outputs are included in the output of the frequency divider 135. Comparator
The 136 confirms the coincidence by taking the logical product of the both.
The standard signal. But the input signal is non-standard
If it is a signal, equations (1) and (2) do not hold.
As shown in (d), the output of the frequency divider 126 is the frequency divider 1
Not included in the output of 35. The comparator 136 detects this discrepancy.
It detects and determines that the input signal is a non-standard signal. The pulse width of the frequency divider 135 output is
Determine standard and non-standard detection sensitivities. That is, pulse width
Is wide, it is easy to detect non-standard signals as standard signals.
If the pulse width is narrow, the standard signal is also judged to be a nonstandard signal.
Will be decided. The comparator 136 operates every vertical period.
If the frequency divider 126 is f_SCTo 455/525/4
The frequency divider 135 divides the frequency by 525525/2.
However, the determination cycle is limited to one vertical cycle.
No, it may be one scanning cycle or one frame cycle, and any value
You can choose to. In this way, whether the signal is a standard signal or a non-standard signal
Impulse noise may be mixed in when determining
Therefore, the malfunction of the sync separation circuit 127 frequently occurs.
It Therefore, the output of the frequency divider 134 is also a normal timing
Therefore, the output of the frequency divider 135 also malfunctions.
In this case, even if the input signal is a standard signal,
Since it is judged, the integration circuit 13
7 is added. FIG. 4 is a block diagram showing this detail. In the figure, 401 is an up-down cow.
, 402 is an OR circuit, 403 is an RS flip-flop
It is Up-count of up-down counter 401
The matching output of the comparator 136 and the down
The unmatched output is input to the und terminal. Up now
The initial value of the down counter 401 is N, and this count value is
Carry output and borrow output at 2N and 0 respectively
Be prepared to gain strength. Also, the emission of these pulses
Corresponding to the raw, OR circuit 402 at the counter 401 low
Create a pulse and set the initial value N with this
To In this case, it is either a match or a mismatch for each vertical cycle.
Since the above input can be obtained, the up / down counter 401
Counts up or down, but either
Carry only when the force is N times more than the other input
-Output or borrow output occurs, and RS flip-flop
Determine set and reset. Therefore, the sync separation times
Even if the path 127 malfunctions, the standard / non-standard judgment is affected.
I can't. Next, the second detection means for non-standard signals will be described.
Disturbance of control voltage used for color burst reproduction for color demodulation
The detection method will be described. In FIG. 1, the frequency divider 125
Output is frequency f_SCColor burst playback output
Therefore, if this is applied to the color demodulation circuit 106, color demodulation is performed.
You can By the way, optical video disc for home use
In players, still mode, quick play,
Alternatively, it is played by special playback such as slow mode.
The signal that has
-The burst signal phase is discontinuous and non-standard
It can be said to be a type of issue. This burst signal
At the phase discontinuity point, the bar input to the phase comparator 122 is
The output of the phase comparator 122 is
Disturbance and, as a result, voltage control for the period until the phase is synchronized again.
The output clock frequency of the oscillator 124 is also disturbed. But
Then, the clock is counted by a predetermined number and the 1-frame delay is
Even if you do, there will be errors due to the disturbance of the clock.
The pixels do not correspond between frames or fields.
Therefore, when processing a normal standard signal,
On the contrary, the image quality is deteriorated. Ie this
Such signals are non-standard signals. In this case, equation (3) is
Since it does not hold, it can be detected by the first detecting means.
However, the above error is very small, so increase the detection sensitivity.
It is necessary to decide whether to count for a long time. Which one
The method also has the problems of misjudgment and large detection time.
Not purposeful. Therefore, in this embodiment, the color burst signal is transmitted.
At the discontinuity point of the signal, the control voltage of the voltage controlled oscillator 124 is
Utilizing the fact that the pressure is disturbed, it is detected that this is disturbed.
The disturbance detection circuit 142 determines that the signal is a non-standard signal, and
The OR circuit 143 calculates the logical sum of the output and the output of the integration circuit 137.
In this way, comprehensive judgment is performed. FIG. 5 shows the configuration of the disturbance detection circuit 142.
In the figure, 151 is an amplifier circuit, and 152 is an absolute value conversion circuit.
, 153 is a comparator, 154 is an RS flip flow
It is up. The amplifier 151 includes the LPF shown in FIG.
The output of 123 is input. The amplifier 151 amplifies this
And sends it to the absolute value conversion circuit 152. Absolute value conversion circuit 152
Rectifies this only in the positive direction as shown in Fig.
And sends it to the comparator 153. The comparator 153 is
It has a constant threshold value and the same
The output shown in FIG.
4 is set as shown in FIG. This makes it non-standard
It can be determined as a signal. In addition, RS flip flow
For example, one vertical cycle from the frequency divider 135
Reset by the pulse of the
No. judgment can be made. Next, horizontal synchronous reproduction will be described.
As described above, 8f in FIG._SCAt the frequency
The oscillating voltage controlled oscillator 130 is 91
Divided by 0 and the frequency is 2f_HA horizontal deflection pulse
Grow This output is output from the horizontal excitation / horizontal output circuit 132.
Deflection yoke and flyback transformer not shown via
133 is driven. The deflection yoke horizontally scans the cathode ray tube.
In addition, the flyback transformer 133 is
Create various high voltage power supplies to drive the receiver. This
The output pulse of the flyback transformer 133 is a frequency divider 1
The frequency is f divided by 2 by 34._HOutput pulse
Is generated and supplied to the phase comparator 128. As above
The output of the sync separation circuit 127 as a reference.
The horizontal synchronizing signal can be reproduced by the PLL circuit. Further, as is already clear, in this embodiment
In addition, using this PLL, line lock clock
In addition, the standard and non-standard signal detection pulses are also generated.
And efficiently use the hardware. This embodiment is explained as a musical example of the present invention.
Although clarified, the following modifications are possible. FIG. 7 shows a second implementation of the preprocessing section 140 of FIG.
This is an example. In FIG. 7, 501 is 2PF
Other parts are the same as shown above. In this embodiment,
Separation of luminance signal and chrominance signal when judged as standard signal
A normal frequency separation method can be used without using a comb filter.
I used it. For operation when a standard signal is input
This is exactly the same as described above. A non-standard signal is input
If the video input signal is input to the 2PF501,
Be done. This is the most representative video source for non-standard signals
Is a home VTR, but this signal is originally high
Since there are few components, only the low frequency components of the input video signal are brightened.
Because it is often possible to regard it as a degree signal,
It Of course, when a non-standard signal is received, subsequent motion adaptation YC
The separation circuits 109 and 110 jump. FIG. 8 shows the second part of the horizontal sync reproducing unit 141 of FIG.
FIG. In FIG. 8, 601 is
Phase comparator, 602 LPF, 603 voltage controlled oscillation
604 is a frequency divider, and the same parts as those shown above have the same numbers.
The number is marked. In this embodiment, the output of the sync separation circuit 127 is
A force for detecting whether the signal is a standard signal or a non-standard signal.
PLL that generates pulse related to in-lock clock
And a sampling clock for sampling non-standard signals.
And the horizontal sync playback section are composed of separate PLL circuits.
It is a thing. In many cases, the configuration shown in FIG.
No problem, but depending on your television receiver:
Problems may occur. That is, the flyback transformer 133
Receives a pulse from the horizontal excitation / horizontal output circuit 132 on the primary side.
Then, a high pressure is generated on the secondary side. The high pressure is a cathode ray tube
It is used as the anode voltage of 120. Where the video
If the signal reproduces a relatively bright screen, the
From the anode of the un-tube 120 to the cathode,
The beam current flows and the high voltage fluctuates as a result, and the effect is
It appears on the primary side of the flyback transformer 133. this
Therefore, the input pulse to the frequency divider 134 (flyback transformer
The pulse width and peak value of the output pulse of the sensor 133)
Will be. This means the following: That is, input
If the video signal is a regular NTSC signal and the horizontal frequency is
Even if there is no jitter or jitter, depending on the brightness of the video signal,
The output of the phase comparator 128 is supplied to the voltage controlled oscillator 130.
A certain error voltage will be generated. Therefore,
Even if the force signal is a normal standard signal, its error voltage is large.
Depending on the smallness, it may be judged as a non-standard signal.
It However, the configuration as shown in FIG.
Therefore, the standard / non-standard detection circuit is the flyback transistor.
Since it is composed of a PLL system that does not include switch 133,
A stable detection operation that does not depend on the image signal content can be performed.
It will be possible. In FIG. 8, the voltage-controlled oscillator 603
Oscillation frequency is 8f_SCThere is no need to select it, for example 2f
_HSet to a low frequency, and divide by 135 for 525 minutes.
If you go around, you can get 1 vertical cycle comparison pulse
It Further, in this embodiment, at the time of non-standard input,
I switched the comb filter to processing in space, but
The deducer and the scan line interpolation circuit are also processed in space (between scan lines).
It doesn't matter if you switch to reason. Digital television reception according to the present invention
FIG. 9 shows a second embodiment of the signal and synchronization processing circuit of the machine.
You In this embodiment, the scanning line interpolation circuit is different from that of FIG.
Therefore, the horizontal deflection frequency is f_HHas become.
Therefore, the frequency divider 134 (two frequency divider) in FIG. 1 is omitted.
The output of the flyback transformer 133 remains in phase.
It is input to the comparator 128. Similar to FIG. 1, modifications of FIGS. 7 and 8 are possible.
Noh. Digital television reception according to the present invention
FIG. 10 shows a third embodiment of the signal and synchronization processing circuit of the machine.
Show. Compared to FIG. 9, this embodiment does not have a noise reducer.
Since only the comb filter is used,
Only the burst lock clock is sufficient for the pulling clock.
Yes. Therefore, no analog line comb filter is required
Is. In this case, the detection result of the non-standard signal is
Select the line comb filter for the comb filter
The control will work like this. [0052] As described above, according to the present invention, the input
Automatically detect whether the signal is a regular standard signal or a nonstandard signal
The signal processing method or clock based on the detected result.
Switch or both, and horizontal
Also for synchronized playback, the input synchronization signal is used as the direct reference.
Since the deflection system is driven by the
It is possible to reproduce the synchronization signal that responds to the promptly.
As a result, even for non-standard signals, scan line interpolation and noise
Synchronous playback with quick follow-up is possible with the processing of the deducer
Therefore, good image quality can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a first embodiment of the present invention. FIG. 2 is a waveform diagram showing a standard signal and a non-standard signal. FIG. 3 is a block diagram showing the operation of a standard / non-standard signal detection circuit. FIG. 4 is a block diagram showing details of an integrating circuit. FIG. 5 is a block diagram showing a control voltage disturbance detection circuit. FIG. 6 is an operation waveform diagram thereof. FIG. 7 is a block diagram showing a first modification example of FIG. FIG. 8 is a block diagram showing a second modified example of FIG. FIG. 9 is a block diagram showing a second embodiment of the present invention. FIG. 10 is a block diagram of a third embodiment of the present invention. [Description of Codes] 102 ... Comb Filter, 109 ... Motion Adaptive Y Separation, 113 ... Noise Reducer, 115 ... Motion Adaptive Scan Line Interpolation, 121 ... Burst Extraction, 127 ... Synchronous Separation, 128 ... Phase Comparator, 130 ... Voltage Control oscillator, 133 ... Flyback transformer, 142 ... Disturbance detection circuit, 401 ... Up-down counter, 402 ... OR circuit, 403 ... RS flip-flop, 501 ... 2PF, 601 ... Phase comparator, 602 ... 2PF, 603 ... Voltage control Oscillator, 604 ... Divider.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazuo Nakagawa             Stock, 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa             Home Appliance Research Laboratory, Hitachi, Ltd.

Claims (1)

[Claims] 1. In a television signal processing device for digitally processing an input signal of a television, at least two types of clocks and an oscillation S
/ N, a clock generating means having a first clock having a good characteristic and a second clock having a relatively good tracking characteristic, and luminance / chromaticity for performing motion adaptive time processing and spatial processing. A space-time signal processing circuit including a separation circuit; and a detection unit that detects whether the input signal is a standard signal or a non-standard signal, the detection unit including a signal corresponding to the first clock and the second signal. Digital television signal processing, characterized in that it includes a comparator for inputting a signal corresponding to the clock signal, and when the detecting means detects a non-standard signal, the luminance / chromaticity separation circuit is switched to processing in space. apparatus. 2. In a television signal processing device for digitally processing an input signal of a television, at least two types of clocks and an oscillation S
/ N, a clock generating means having a first clock having a good characteristic and a second clock having a relatively good tracking characteristic, and luminance / chromaticity for performing motion adaptive time processing and spatial processing. A spatiotemporal signal processing circuit including a separation circuit; and a detection unit that detects whether the input signal is a standard signal or a nonstandard signal, the detection unit including the first clock generation unit and the clock generation unit. A first frequency dividing circuit for dividing the output by a predetermined number, a pulse generating circuit for generating a pulse of a predetermined multiple of the horizontal synchronizing signal contained in the input signal as a reference, and an output of the pulse generating circuit. A second frequency dividing circuit that divides the frequency by a predetermined number, a comparator that inputs the outputs of the second frequency dividing circuit and the first frequency dividing circuit, and an integrator that integrates the output of the comparator, When this detection means detects a standard signal The brightness and
A digital television signal processing apparatus, wherein the chromaticity separation circuit is switched to time processing, and when the detecting means detects a non-standard signal, the luminance / chromaticity separation circuit is switched to processing in space. 3. In a television signal processing device for digitally processing an input signal of a television, at least two types of clocks and an oscillation S
/ N, a clock generating means having a first clock having a good characteristic and a second clock having a relatively good tracking characteristic, and luminance / chromaticity for performing motion adaptive time processing and spatial processing. A spatiotemporal signal processing circuit including a separation circuit; and a detection unit that detects whether the input signal is a standard signal or a nonstandard signal, wherein the detection unit includes the first clock generation unit and the clock generation unit. A first frequency dividing circuit for frequency-dividing an output by a predetermined number, the second clock generating means, a third frequency dividing circuit for frequency-dividing an output of the second clock generating means by a predetermined number, and the third frequency dividing circuit. And a comparator for inputting the output of the first frequency dividing circuit, and an integrator for integrating the output of the comparator. When the detecting means detects a standard signal,
A digital television signal processing apparatus, wherein the chromaticity separation circuit is switched to time processing, and when the detecting means detects a non-standard signal, the luminance / chromaticity separation circuit is switched to processing in space. 4. In a television signal processing device for digitally processing an input signal of a television, at least two types of clocks and an oscillation S
/ N, a clock generating means having a first clock having a good characteristic and a second clock having a relatively good tracking characteristic, and luminance / chromaticity for performing motion adaptive time processing and spatial processing. A space-time signal processing circuit including a separation circuit and a noise reducer circuit, and a detection unit that detects whether the input signal is a standard signal or a non-standard signal, the detection unit being a signal corresponding to the first clock. , A comparator for inputting the signal corresponding to the second signal, and when the detection means detects a non-standard signal, the luminance / chromaticity separation circuit is switched to processing in space and the noise reducer circuit A digital television signal processing device characterized by being driven by two clocks. 5. In a television signal processing device for digitally processing an input signal of a television, at least two types of clocks and an oscillation S
/ N, a clock generating means having a first clock having a good characteristic and a second clock having a relatively good tracking characteristic, and luminance / chromaticity for performing motion adaptive time processing and spatial processing. A spatio-temporal signal processing circuit including a separation circuit and a scanning line interpolation circuit, and a detection unit that detects whether the input signal is a standard signal or a non-standard signal, the detection unit being a signal corresponding to the first clock. And a comparator for inputting the second-corresponding signal, and when the detection means detects a non-standard signal, the luminance / chromaticity separation circuit is switched to a process in space and the scanning line interpolation circuit is included. Is driven by a second clock, a digital television signal processing device.