JPH0239689A - Motion detecting circuit - Google Patents

Abstract

PURPOSE:To obtain a motion detecting signal of the high band of a video signal by detecting the differential between first and second frames having the time difference for one field period out of a video signal, and obtaining the differential of the respective high bands. CONSTITUTION:First frame differential detecting means 501Y, 502Y and 531A and second frame differential detecting means 501Y to 501Y and 531B are possessed, the differential between the first and second frame having the time difference for one field period is detected, the differential of the respective high band components is obtained, and it becomes the motion detecting signal of the high band. In such a case, since a chrominance signal components are in phase inverted relation between the frame and line, the chrominance signal components, namely dot disturbing components, are included in the high band components of the differential between the first and second frames, whereas, the chrominance signal components becomes at the same amplitude and the same phase in the case of a still picture, and the difference becomes 0. Thus, the error generation due to the chrominance signal component is prevented, and the motion detecting signal of the high band can be obtained.

Description

[Detailed description of the invention] The present invention will be explained in the following order.

A. Field of industrial application B. Overview of the invention C. Prior art D. Problem to be solved by the invention E. Means for solving the problem (Fig. 4) F. Effect G. Example G, overall explanation (Fig. 1) Explanation of G2 signal processing circuit (Fig. 2) Explanation of G3 motion detection circuit (Fig. 4) H Effect of the invention A Industrial application field This invention is applicable to high-level applications such as motion-adaptive missed scan line interpolation, such as the so-called 10TV. A television receiver that performs image quality processing,
The present invention relates to a motion detection circuit suitable for use in obtaining motion detection signals.

B. Summary of the Invention The present invention detects the first and second frame differences having a time difference of one field period from the video signal, and obtains the difference in the high frequency components of each, thereby increasing the high frequency of the video signal. This is to obtain a good motion detection signal in the area.

Furthermore, in the vertical decorrelation section, the difference between the high-frequency components is not used as a high-frequency motion detection signal, thereby preventing detection errors due to color signal components (dot interference components) from occurring.

C. Prior Art FIG. 12 shows the configuration of an example of a television receiver.

In the figure, the video signal from the input terminal (62) is A
After being converted into a digital signal by a /D converter (63), it is supplied to a Y/C separation circuit (64) where it is separated into a luminance signal Y and a color signal C.

The luminance signal Y output from the Y/C separation circuit (64) is
It is supplied to the scanning line interpolation circuit (65Y). The color signal C output from the Y/C separation circuit (64) is supplied to the chroma decoder (66) and is color demodulated.The red difference signal R-Y and blue difference signal output from this chroma decoder (66) are The time division signal R-Y/B-Y of the signal B-Y is supplied to the scanning line interpolation circuit (65C), and from this scanning line interpolation circuit (65Y), (65C), the main scanning line signal Ym
, Rm-Ym/Bm-Ym, interpolated scanning line signals Yc, Rc-Yc/Bc-Yc are output simultaneously.

Further, the luminance signal Y output from the Y/C separation circuit (64) is supplied to a motion detection circuit (50), and the motion detection signal from this motion detection circuit (50) is sent to a coefficient generator (51).
supplied to Scanning line interpolation circuit (65Y), <65C
) is generated by this coefficient generator (51), and the value is changed depending on the magnitude of the motion detection signal. For example, in a still image portion, K=0, and the maximum value of K is 1.

The motion detection circuit (50) is configured as shown in FIG. ) and (402).The field memories (401) and (4
The delay time of the series circuit of 02) is 1 frame (263H
+262H).

The human input signal of field memo IJ (401) and the output signal of field memo U (402) are input to the subtracter (
403) and is subtracted. This subtractor (403
) The frame difference signal output from the frame difference signal is converted into an absolute value by an absolute value circuit (405) after high-frequency noise components and dot interference components are removed by a low-pass filter (404). The output signal of this absolute value circuit (405) is used as a motion detection signal.

Note that detecting motion from a frame difference signal in this manner is described in, for example, Japanese Patent Laid-Open No. 55-8124.

The scanning line interpolation circuit (65Y) is configured as shown in FIG. In the same figure, the Y/C separation circuit (64)
The luminance signal Y supplied from the line memory (601) is supplied to a line memory (601) that constitutes a delay line. This line memo IJ
The input signal and output signal of (601) are sent to the adder (601).
02) for addition and averaging, and this adder (602
) The output signal of K (K≦
1) After being multiplied, it is supplied to the adder (604).

Furthermore, the luminance signal Y is supplied to a field memory (605) that constitutes a delay line. This field memo! J
The delay time at (605) is 263H. The output signal of this field memo IJ (605) is multiplied by (1-K) by a coefficient unit (606) and then supplied to an adder (604).

FIG. 15 is a diagram showing the scanning line structure on the time-vertical plane, and the ◯ marks indicate the scanning lines of each field. The above-mentioned human input signal is h, and the output signal of line memo U (601) is 1.
If the output signal of one field memory (605>) is J, these signals h-j have the positional relationship shown in FIG.

In the scanning line interpolation circuit (65Y), the adder (60
2) and field memo IJ (605)
The output signal J becomes an interpolated scanning line signal for the still image portion. Therefore, the adder (604) outputs an interpolated scanning line signal Yc in which the interpolated scanning line signals of the moving image part and the still image part are added at a ratio according to the degree of movement.

The interpolation scanning line is located at the position marked with :: in FIG.

Further, the human input signal is directly used as the main scanning line signal Ym.

Although the description is omitted, the scanning line interpolation circuit (65C) is similarly configured.

Main scanning line signals Ym, Rm -Ym/Bm output from the scanning line interpolation circuits (65Y) and (65C)
-Ym, interpolated scanning line signal Yc, Rc -Yc/
Bc - Yc are respectively time compression circuits (67Y);
(67c). This time compression circuit (6
7Y), (b7C), the main scanning line signal Ym.

Rm −Ym/Bm −Ym and interpolated scanning line signal Yc,
Rc-Yc/Bc-Yc are each time-axis compressed to 1/2 and output continuously. In this case, the time compression circuit (67C) separately outputs a red difference signal and a blue difference signal.

The double-speed luminance signal and color difference signal output from the time compression circuits (67Y) and (67C) are converted into analog signals by D/A converters (68Y), (68R), and (68B), respectively.

D/A converter (68Y), (68R), (68B)
The double-speed luminance signal and color difference signal outputted from the matrix circuit (73) are respectively supplied to a matrix circuit (73). The double-speed red, green, and blue signals R1G and B outputted from this matrix circuit (73) are supplied to amplifiers (74R) and (74
G), color picture tube (75) via (74B)
The color picture tube (75) displays non-interlaced scanning with twice the number of scanning lines.

D Problems to be Solved by the Invention By the way, a motion detection circuit (50
), a low-pass filter (404) is arranged on the output side of the subtracter (403) in order to remove high-frequency noise components and dot interference components, so that the high-frequency range of the output signal of the subtractor (403) is The components are removed by a pass filter (404). Therefore, a high-frequency motion detection signal could not be obtained, and the detection ability was degraded.

Therefore, one object of the present invention is to make it possible to obtain a high-frequency motion detection signal in good condition.

E. Means for Solving the Problems This invention provides a first frame difference detection means (501Y) for detecting a first frame difference from a video signal.

(502Y) (531^) and second frame difference detection means (531^) for detecting a second frame difference delayed by one field period from the first frame difference from the video signal.
501Y), (502Y), (503Y) (53
1B) and first and second frame difference detection means (5
01Y), (502Y) (531A) and (
501Y), (502Y), (503Y) (53
1B> output signals are supplied, respectively.
low-pass filters (537^) and (537B), and the first and second low-pass filters (537^)
and (537B), the subtracter (5
38).

The switch means (554) is arranged on the output side of the subtracter (538), and vertical correlation detectors (551) to (553) detect vertical correlation from the video signal. , vertical correlation detectors (551) to (553), and may be turned off in the vertical decorrelation section.

F Effect In the above-described configuration, the first and second frame differences having a time difference of one field period are detected from the video signal, and the difference in their high frequency components is obtained, which becomes a high frequency motion detection signal. . In this case, since the color signal components have a phase inversion relationship between frames and lines, the high frequency components of the first and second frame differences each include color signal components (dot interference components), but these color signal components If the signal components are still images, they will have equal amplitude and the same phase, and the difference will be zero. Therefore, it is possible to obtain a high-frequency motion detection signal without causing detection errors due to color signal components (dot interference components).

Furthermore, in the vertical decorrelation section, the color signal components are not inverted between lines, and the difference in high frequency components is not 0, resulting in a detection error. A switch means (5
54), and controlling this switch means (554) with vertical correlation detectors (551) to (553),
By not using this difference as a motion detection signal in the vertical decorrelation section, it is possible to prevent detection errors from occurring.

G Example GI overall explanation (Figure 1) FIG. 1 shows an entire embodiment of the present invention.

In the same figure, the video signal from the input terminal (1) is input to a Y
The signal is supplied to the /C separation circuit (2) and separated into a luminance signal Y and a color signal C.

The luminance signal Y output from the Y/C separation circuit (2) is A
After being converted into a digital signal by the /D converter (3Y), it is supplied to the signal processing circuit (5Y). The color signal C output from the Y/C separation circuit (2) is sent to the chroma decoder (4).
) for color demodulation. This chroma decoder (4
) red difference signal R-Y and blue difference signal B-Y output from
is converted into a digital signal by an A/D converter (3C) and then supplied to a signal processing circuit (5C) as a time-division signal RY/B-Y.

The signal processing circuits (5Y) and (5C) perform signal processing such as scanning line interpolation.
The double-speed luminance signal and color difference signal output from (5C) are sent to D/A converters (6Y), (6R), and (6), respectively.
B) is used as an analog signal.

(7) is a clock generation circuit, and this generation circuit (7)
A horizontal synchronizing signal HD separated from the video signal is supplied to the circuit, and a clock CLKH phase-locked to the horizontal synchronizing signal HD is output from this generating circuit.

D/D from the above-mentioned A/D converters (3Y) and (3C)
The clock CLKH from this generation circuit (7) is supplied to the digital processing system up to the A converters (6Y), (6R), and (6B).

The double-speed luminance signal and color difference signal output from the D/A converters (6Y), (6R), and (6B) are
It is supplied to JJ Kusuji (8). This ma) double-speed red, green, and blue signals R, which are output from the IJ circuit 8),
G and B are amplifiers (9R), (9G), (
9B) to a color picture tube (10), where non-interlaced scanning display with twice the number of scanning lines is performed.

G. Explanation of the signal processing circuit (Figure 2) Figure 2 shows the configuration of the signal processing circuit (5Y) and (5C). First, the signal processing circuit (5Y) for the luminance signal system will be explained. .

In the figure, a luminance signal Y converted into a digital signal by an A/D converter (3Y) is supplied to a field memory (501Y) forming a delay line. This field memory (501Y) is configured as a so-called 3-port field memory, and has a first output terminal with a delay time of 263H and a second output terminal with a delay time of 262H. The output signal of the first output terminal of this field memory (501Y) is the field memory (502Y) that constitutes the delay line.
Y). This field memo IJ (502Y
) is set to 262H. The output signal of this field memory (502Y) is supplied to field memo 'J (503Y) which constitutes a delay line. The delay time in this field memo 'J (503Y) is 26
It is considered 2H.

The human input signal of the field memo IJ (501Y) and the output signal of the field memory (502Y) are transferred to the adder (504
Y) and is averaged by this adder (504Y).
) output signal is 1-K (-≦1
) and then supplied to the adder (511Y). The output signals of the first output terminal and the second output terminal of Field Memo 'J (501Y) are supplied to the adder (505Y) and averaged, and the output signal of this adder (505Y) is sent to the coefficient multiplier (508Y). ) is doubled by the adder (
511Y). Field Memo'J (50
The output signal of the second output terminal of 1Y) and the output signal of field memo U (503Y) are supplied to an adder (506Y) and averaged, and the output signal of this adder (506Y) is sent to a coefficient multiplier (509Y). After being multiplied by 1- in , it is supplied to an adder (512Y).

The output signal of the second output terminal of field memo U (501Y) is doubled by a coefficient multiplier (510Y) and then supplied to an adder (5L2Y).

Further, (530) is a motion detection circuit, and a motion detection signal from this motion detection circuit (530) is supplied to a coefficient generator (541). The above-mentioned coefficient machine (507
The values in Y) ~ (510Y) are determined by this coefficient generator (
541), and its value is changed depending on the magnitude of the motion detection signal. For example, in the still image part = 0
The maximum value of K is 1.

Field memory (501Y) to (503Y) mentioned above
, adders (504Y) to (506Y), (511Y)
, (512Y), coefficient unit (507Y) ~ (510Y)
A scanning line interpolation circuit (5QOY) is configured.

Figure 3 is a diagram showing the scanning line structure on the time-vertical plane.
The marks indicate the scan lines of each field.

Field memo of the above-mentioned scanning line interpolation circuit (500Y)! The input signal of J (501Y) is a The output signal of its first output terminal is C1 The output signal of its second output terminal is b
The output signal of 1 field memo 'J (502Y) is d,
Field memo! Assuming that the output signal of J (503y) is e, these signals a-e have the positional relationship shown in FIG.

Field memo in the scanning line interpolation circuit (500Y)! The output signal of the second output terminal of J (501Y) becomes the main scanning line signal of the moving image part, and also serves as the main scanning line signal of the moving image part.
)Become. Therefore, from the adder (512Y), the main scanning line signal Ym obtained by adding the main scanning line signals of the moving image part and the still image part at a ratio according to the degree of movement becomes the interpolated scanning line signal of the output still image part. Together with this, it becomes a summing line signal. Therefore, from the adder (511Y),
An interpolated scanning line signal Yc is output, which is obtained by adding the interpolated scanning line signals of the moving image portion and the still image portion at a ratio corresponding to the degree of movement. Note that the interpolation scanning line is located at the position marked with :: in FIG.

The main scanning line signal Ym and the interpolated scanning line signal Yc outputted from the scanning line interpolation circuit (500Y) in this way are respectively supplied to the time compression circuit (521Y). In this time compression circuit (521Y), the main scanning line signal Ym and the interpolation scanning line signal Yc are each compressed in time by 1/2 and output continuously. In other words, this time compression circuit (5
21Y) outputs a double-speed luminance signal.

Next, the color signal system signal processing circuit (5C) will be explained. This signal processing circuit (5C) is a scanning line interpolation circuit (5C).
00C) and a time compression circuit (521C), and the scanning line interpolation circuit (500C) is composed of the above-mentioned signal processing circuit (521C).
It is configured similarly to the scanning line interpolation circuit (500Y) of Y). Note that the values of the coefficient unit of this scanning line interpolation circuit (500C) are also generated by the above-mentioned coefficient generator (541).

This scanning line interpolation circuit (500C) includes an A/D converter (
3C) red difference signal R-Y converted into a digital signal
, the time-division signal R-Y/B-Y of the blue difference signal B-Y is supplied, and the main scanning line signal Rm -Ym 78m-Ym
, interpolated scanning line signals Rc-Yc/Bc-Yc are output.

In this way, the main scanning line signal Rm - Ym / Bm - Ym and the interpolated scanning line signal Rc - Yc / Bc - Yc output from the scanning line interpolation circuit (500C) are respectively supplied to the time compression circuit (521C). . In this time compression circuit (521C), the main scanning line signal Rm -Ym/
Bm -Ym and interpolated scanning line signal Rc -Yc/B'c
-Yc are compressed in time axis to 1/2 and output continuously.

In this case, the time compression circuit (521C) separately outputs a red difference signal and a blue difference signal. In the end, this time compression circuit (521C) outputs a double-speed color difference signal.

In this case, in the scanning line interpolation circuit (500Y), since it is a static signal, the dot interference component (color signal component) contained in the luminance signal Y is canceled out and removed. Furthermore, since similar processing is performed in the scanning line interpolation circuit (500C), the cross color components included in the time-division signals RY/BY are also canceled out and removed.

That is, the color signal output from the Y/C separation circuit (2) is expressed by the conceptual formula YH+Co51n2πf set. Here, Y) is a luminance signal component, and fsc is a color subcarrier frequency. Therefore, when this color signal is converted to 11 tones, the following equation is obtained.

Color signal X5in2πf 5et =YH's+n2rr f5(t+C.

Therefore, the cross color component YH-5ln2πf s
Since ct has the same phase as the color signal component and has a phase inversion relationship between frames, the scanning line interpolation circuit (
500C) and are removed.

Also, scanning line interpolation circuit (500Y), (500C)
In the still image part, inter-frame addition processing is performed, so noise that exists randomly in the time direction is reduced to 1/
4, and the S/N of the luminance signal and color signal increases.

G. Configuration of motion detection circuit (FIG. 4) FIG. 4 shows the configuration of the motion detection circuit (530).

The field memories (501Y) to (503Y) of the scanning line interpolation circuit (500Y) in the example of FIG. 2 are commonly used as the field memories (501Y) to (503Y) in the figure.

In the figure, the human input signal of the field memory (501Y) and the output signal of the field memo 'J (502Y) are supplied to a subtracter (531A>) and subtracted therefrom.

The frame difference signal output from this subtracter (531A) is passed through a low-pass filter (532A, ), (532A2), which removes high-frequency noise components and dot interference components.
supplied to As the filter (532A), for example, 3 and 5 corresponding to the frequency of the dot interference component are used.
A COS filter (the frequency characteristics are shown by the solid line a in Figure 5) whose response decreases around 8 MHz is used,
On the other hand, as a filter (532A2), for example, 3, 58! corresponds to the frequency of the dot interference component. A C082 filter (the broken line in FIG. 5 already shows the frequency characteristics) whose response decreases around JHz is used.

The output signals of the filters (532A,) and (532A2) are supplied to fixed terminals on the a side and b side of the changeover switch (535A), respectively. This changeover switch (5
The output signal of 35^) is converted into an absolute value by an absolute value circuit (533A) and is supplied to an adder (534).

Second output terminal of field memory (501Y) and field memo! Output signal of J (503Y): Well, it is supplied to the subtracter (531B) and subtracted.

The frame difference signal output from this subtracter (531B) is passed through a low-pass filter (532B+) (53282) that removes high-frequency noise components and dot interference components.
supplied to Filter (532B,), (53
2B2) are filters (532A,), respectively.
It is said to have the same characteristics as (532^2). The output signals of the filters (532B,), (532B,) are supplied to fixed terminals on the a side and b side of the changeover switch (535B), respectively. This changeover switch (535B
The output signal > is converted into an absolute value by an absolute value circuit (533B) and is supplied to an adder (534).

The output signal of this adder (534) is then supplied to an adder (536) as a low-frequency motion detection signal.

Also, the output signals of the subtracters (531^) and (531B) are 3 and 58M) whose center frequencies correspond to the frequencies of the color signal components, respectively. Bandpass filter (537^) with z.

(537B) to a subtracter (538). The output signal of this subtracter (538) is converted into an absolute value by an absolute value circuit (539), and then is converted to an absolute value by a switch circuit (539).
554) and is supplied to an adder (536) as a high-frequency motion detection signal. And an adder (536
) is used as a motion detection signal.

Also, (551) is a vertical correlator, and this vertical correlator (551) has a field memory (501).
The vertical correlator (551) outputs the absolute value of the line difference signal. This vertical correlator (
The output signal of 551) is passed through a low-pass filter for noise removal (552) to a level comparator (553).
supplied to This level comparator (553) outputs a high level "1" signal when the supplied line difference signal is above a predetermined level, and outputs a low level #0 signal when it is below a predetermined level. That is, the vertical correlation section outputs a low level "0" signal, and the vertical non-correlation section (vertical edge section) outputs a high level "1" signal.

The above-mentioned changeover switch (535^), (535B)
is controlled by the output signal of this level comparator (553), and is connected to the a side in the vertical correlation section, and
In the vertical decorrelation section, it is connected to the b side.

Further, the above-mentioned switch circuit (554) is controlled by the output signal of this level comparator (553), and the vertical correlation section outputs the input signal as it is, and the vertical non-correlation section outputs 0. .

Such a motion detection circuit (530) obtains a low-frequency motion detection signal by adding two frame difference signals, so it can also detect fast motion between fields (1/60 sec>). For example, signal a.

When b, d, and e are respectively shown as A, B, C, and D in FIG. 6, the output signals of the subtracters (531A) and (531B) are as shown in E and F, respectively, in the same figure. Therefore, using only the output signal of the subtracter (531^), the portion P is determined to be a still image portion, and movement between fields cannot be detected. Therefore, by further using the output signal of the subtracter (531B), the detection signal becomes as shown in G in the figure, and fast movements between fields can also be detected.

In addition, in the vertical non-correlation part (vertical edge part), the attenuation rate is switched to the filter (532A2), (532B2) side that is steep, and in the vertical correlation part (the part other than the vertical edge part), the filter is switched to the filter with a gentle attenuation rate. (532A
＋＞.

Since it is switched to the (532B,) side, it is possible to effectively remove dot interference components and also to sufficiently detect movements at relatively high frequencies.

In addition, a band pass filter (53'7A), (537
B) outputs the high frequency components of the frame difference signals, and the difference between these is output from the subtracter (538). In this case, the dot interference component (color signal component)
As shown in FIG. 7, there is a phase inversion relationship between frames and between lines, so a bandpass filter (537A) is used.

The high-frequency components of the frame difference output from (537B) each include a dot interference component. If these dot interference components are a still image, they are shown in FIG. 8A.

As shown in the figure, the amplitude and phase are equal, and the subtractor < 538
), the difference output from the equation becomes 0, as shown in C in the same figure.

Therefore, a high-frequency motion detection signal can be obtained satisfactorily without detection errors caused by dot interference components.

In addition, in the vertical decorrelation section, as shown in FIG. 9, the color signal components are not inverted between lines, and the bandpass filter
The disturbance components included in the high frequency components of the frame difference output from A) and (537B) do not have the same amplitude and phase even in still images, as shown in Figures 10A and B.
The difference output from the subtracter (538) is as shown in C in the same figure, resulting in a detection error. In the example shown in FIG. 4, in the vertical decorrelation section, the output of the switch circuit (554) is set to 0 to prevent this difference from being used as a motion detection signal, thereby preventing the occurrence of detection errors due to dot interference components. I can do C.

In FIGS. 7 and 9, the ○ mark indicates the scanning line of each field, and the 4:: mark indicates the position of the interpolation scanning line.

% indicates the phase of the dot interference component.

FIG. 11 shows a pattern in which a motion detection signal cannot be obtained by low-frequency motion detection, but a motion detection signal can be obtained by high-frequency motion detection. Figure A,
B, C, and D are field memories (501Y).
Human input signal, field memory (501Y), (50
2Y) and (503Y) are shown.

At this time, subtractor (531A), (531B) C
) The output signals are as shown in E and F of the figure, respectively.

The output signals of these subtracters (531^ha(531B>) are filtered by low-pass filters (532A, ), (532A2),
The low-frequency motion detection signal that is not output from (532B+) and (532B2) but is output from the adder (534) becomes 0 as shown in H in the figure. On the other hand, the output signals of the subtractors (531A) and (531B) are outputted from the bandpass filters (537A) and (537B), and the high-frequency motion detection signal outputted from the subtractor (538) is It becomes as shown in G in the same figure. In addition, the subtracters (531A) and (531B) shown in E and F of the same figure
The frequency of the output signal is determined by a low-pass filter (532A+
), (532A2).

Of course, the frequency is outside the passband of (532B,) and (53282).

In the above embodiment, an example was described in which a high-frequency motion detection signal is obtained from the Y/C separated luminance signal. For example, if the human input signal is a composite video signal, the luminance signal Y Motion detection of the color signal e can be performed simultaneously with high frequency motion detection.

In addition, in the above embodiment, the band pass filter (5
37A) and (537B), but a bypass filter may be provided instead. In short, it only needs to be a low-pass filter.

H Effects of the Invention According to the invention, first and second frame differences having a time difference of one field period are detected from the video signal, and the difference in high frequency components of each is used as a high frequency motion detection signal. Therefore, a high-frequency motion detection signal can be obtained without causing detection errors due to color signal components (dot interference components).

As a result, the detection ability of the motion detection circuit can be significantly improved compared to motion detection only in low frequencies. Also,
In the vertical decorrelation section, the switch means is controlled to prevent the above-mentioned difference in high frequency components from being used as a motion detection signal, thereby making it possible to prevent detection errors from occurring.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the entire embodiment, Fig. 2 is a block diagram of the signal processing circuit, Fig. 3 is a diagram showing the scanning line structure in the time-vertical plane, and Fig. 4 is a block diagram of the motion detection circuit. , Figures 5 to 11
The figure is for the purpose of explanation, FIG. 12 is a configuration diagram of an example of a television receiver, FIG. 13 is a configuration diagram of a motion detection circuit,
Fig. 14 is a configuration diagram of the scanning line interpolation circuit, and Fig. 15 is a time-interpolation circuit diagram.
FIG. 3 is a diagram showing a scanning line structure in a vertical plane. (501Y) to (503Y) are field memories, (503Y)
31A). (531B), (53g) is a subtractor, (5328l)
, (532A2), (532B+). (532B2), (552) are low-pass filters, (533A) (533B), (539) are absolute value circuits, (534), (536) are adders, (535
8), (535B) is a changeover switch, (537^),
(537B) is a band pass filter, (551)
is a vertical correlator, (553) is a level comparator, (55
4) is a switch circuit. ＾ B Kiyu 14 Questions Time Xi 2 Yonaga Naoichi's Walk, Scroll Station 艷 绷织之Ho Perforation Atsushi 7 Figure Bow ~ Bamboo Time Time Vertical Plane 1 Practice Site Figure 8 Figure 10

Claims (1)

[Claims] 1. A first frame difference detection means for detecting a first frame difference from a video signal; and a second frame delayed from the first frame difference by one field period from the video signal. a second frame difference detection means for detecting a difference; first and second low-pass filters to which output signals of the first and second frame difference detection means are respectively supplied; a subtracter to which the output signal of the low-pass filter is supplied. 2. Switch means disposed on the output side of the subtracter, and a vertical correlation detector for detecting vertical correlation from the video signal, wherein the switch means is controlled by the vertical correlation detector and detects vertical non-correlation. 2. The motion detection circuit according to claim 1, wherein the motion detection circuit is turned off in some parts.