JP3040251B2 - Motion detection circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motion detecting circuit required in connection with signal processing of a television signal.

More specifically, in a motion-adaptive Y / C separation circuit for a television signal, if an image of an input television signal is a still image, Y / C separation between frames using a frame correlation is performed to obtain a moving image. In this case, Y / C separation in the field is performed. At this time, it is necessary to first detect whether the image of the input television signal is a still image or a moving image, and the motion detection circuit performs this. is there. The present invention relates to such a motion detection circuit.

[0003]

2. Description of the Related Art Motion adaptive signal processing (motion adaptive Y / Y) for switching the processing of a television signal in accordance with the motion of an image.
C separation) is a very effective means for obtaining high image quality. For example, by performing Y / C separation processing using a frame correlation for a still image and a line correlation for a moving image with respect to a composite color television signal of the NTSC system, image quality such as dot disturbance and cross color is impaired. The occurrence can be suppressed.

As for scanning line interpolation, by performing inter-field interpolation for a still image and inter-line interpolation for a moving image, line flicker can be prevented and the vertical resolution of the screen can be improved. The motion detection circuit detects the presence or absence of motion in the image, determines whether the image is a still image or a moving image, and outputs a control signal that controls the processing method of the motion adaptive signal processing. .

As a conventional example of the motion detecting circuit, there is one disclosed in, for example, Japanese Patent Application Laid-Open No. Hei 2-223288. The configuration of this conventional example is shown in a block diagram in FIG. 2 and will be briefly described below.

In FIG. 2, reference numeral 201 denotes an inter-frame motion detection circuit, 202 denotes a frame memory (1H indicates one horizontal scanning period), 203 denotes a subtraction circuit, 204 denotes an LPF (low-pass filter), and 205 denotes an absolute value circuit (ABS). ), 20
6 is a noise removing circuit, 207 is a first line memory, 2
08 is a minimum value selection circuit, 209 is a spatiotemporal processing circuit, 21
0 is the maximum value selection circuit, 211 is the second line memory, 2
Reference numeral 12 denotes an attenuation circuit, and 213 a field memory.

Here, a case will be described as an example where a composite color television signal of the NTSC system (hereinafter referred to as a television signal) is inputted from an input terminal I. In the inter-frame motion detection circuit 201, the frame memory 202 outputs the television signal input from the input terminal I with a delay of one frame period (525H).

[0008] The subtraction circuit 203 outputs a difference signal between one frame of the input television signal. Here, when the difference signal between one frame is zero, the image of the television signal is determined to be a still image, and when the difference signal is not zero, it is determined to be a moving image, whereby motion of the image can be detected.

However, in the NTSC television signal, the luminance signal component has the same phase and the chrominance signal component has the opposite phase in one frame. Therefore, the one-frame difference signal includes the motion component in addition to the motion component. , And color signal components (components resulting from the addition of color signals having opposite phases by subtraction). Therefore, the color signal component is removed by limiting the color signal band with the LPF 204 with respect to the one-frame difference signal.

Next, the absolute value circuit 205 removes the positive and negative polarities of the difference signal to obtain a motion signal. Thereafter, the noise removal circuit 206 prevents erroneous detection due to noise in the motion signal. That is, the minimum value selection circuit 208 selects the minimum value by comparing with the motion signal detected on one line. further,
The spatio-temporal processing circuit 209 extends the motion signal in the temporal direction and the spatial direction.

That is, in the maximum value selection circuit 210, the motion signal detected one field before (262H, 263H) is attenuated by the attenuator 212 and compared with the motion signal obtained by feedback, and the maximum value is selected. Output. Thus, the conventional example realizes a motion detection circuit with few errors even for an image having a relatively fast motion or an image with a fine pattern.

[0012]

The detection errors when detecting the motion of an image include the following two types of detection errors. The first is an error of detecting that a still image has motion. This is referred to as erroneous detection. The second is
It is an error to detect no motion for a moving image. This will be referred to as detection leakage.

The spatiotemporal processing circuit 209 in the above-described conventional motion detection circuit is designed to detect a relatively fast image motion which is difficult to detect by the inter-frame motion detection circuit. However, this spatio-temporal processing circuit has a problem of causing erroneous detection of motion.

The noise elimination circuit 206 has an effect of reducing erroneous motion detection using noise as image motion. However, this noise elimination circuit has a problem in that the detection of motion is missed in the edge portion of the image.

Hereinafter, a process of detecting a motion of a fast moving image will be described with reference to FIG. FIG. 3 is an explanatory diagram showing a detection result of a motion signal by the conventional motion detection circuit (FIG. 2).

FIG. 3A is a scanning line structure diagram when scanning lines are viewed from the lateral direction, and each square represents a horizontal cross section of one scanning line. More specifically, in FIG. 3A, the horizontal axis is the time (field) direction,
The vertical axis indicates the vertical direction of the screen, and a black-level object (indicated by three black squares) moves from the bottom of the screen to the top of the screen in a white-level background (indicated by white squares) over a two-field elapsed period. ,
An image with five moving lines is shown.

As described above, black squares represent black-level scanning line signals representing an object, and white squares represent white-level scanning line signals representing a background. Also, in (b), (c), (d), and (e) of FIG. 3, black circles represent motion signals, and white circles represent motion images determined to be still images. The black colored triangles are motion signals obtained by feeding back the motion signal determined to be a moving image by the spatiotemporal processing circuit 209.

It is assumed that the current field of interest is the n field in FIG. First, a motion signal detected by the inter-frame motion detection circuit 201 includes an n-field video signal (scanning line signal), a (n−2) -field video signal (scanning line signal) corresponding to one frame before, and 3B is shown as a black circle or a white circle for each of the corresponding scanning line signals.

In the motion signal shown in FIG.
The motion of the pixels P and Q is missed. (If the difference between the signal of the n-th field and the signal of the (n-2) -th field is calculated, the pixels P and Q are determined to be zero and a still image in (b). In practice, a black circle is present at the corresponding position of the (n-1) field to indicate that the image is a moving image. Is a missed detection).

After that, the noise elimination circuit 206 selects the minimum value with the motion signal on one line, and thereby selects the minimum value as shown in FIG.
Of the motion signals shown in FIG.
The movement of S is missed by detection (as a result of the selection of the minimum value, the previous black circle changes to a white circle and detection is missed).

Finally, the spatio-temporal processing circuit 209 attenuates the motion signal detected one field before and feeds back the signal after attenuation, and the motion signal shown in FIG. 3 (d) and the motion signal shown in FIG. 3 (c). The maximum value selection with the motion signal is performed by the maximum value selection circuit 210 of the spatiotemporal processing circuit 209.

The result is shown as a motion signal in FIG.
In the pixels P, Q, and R, it is possible to correct missing motion, but in the pixel S, missing motion is detected. Conversely, motion is erroneously detected for pixels T, U, and V.

In the above-described conventional motion detection circuit, as described above, erroneous motion detection frequently occurs for a fast-moving image, so that it is difficult to appropriately control motion adaptive signal processing. .

For example, when a motion adaptive Y / C separation circuit is controlled by a motion signal generated by a conventional motion detection circuit, a pixel S which is a moving image has a pixel signal due to a motion signal whose motion has been missed. Since Y / C separation processing for a still image using the frame correlation with W is performed, there is a problem that dot disturbance and cross color are generated.

An object of the present invention is to overcome the problems in the prior art as described above and to enable appropriate motion adaptive signal processing to be performed even on a fast-moving image.
An object of the present invention is to provide a highly accurate motion detection circuit.

[0026]

In order to achieve the above object, according to the present invention, a motion detecting circuit includes an inter-frame motion detecting circuit, an inter-field motion detecting circuit, a detection output from the inter-frame motion detecting circuit, and A motion signal mixing circuit that takes in the detection output from the inter-field motion detection circuit, mixes the two, and outputs the mixed signal; and a motion detection control circuit that determines the mixing condition in the motion signal mixing circuit and instructs the motion signal mixing circuit. And was constituted by.

A distinctive feature of the present invention is that, in motion detection of an image, motion detection is performed between fields in addition to motion detection between frames, and both motion signals are mixed to obtain a motion detection signal. In addition, the mixing method is controlled in accordance with the field correlation and the line correlation of the inter-frame motion signal.

[0028]

The inter-frame motion detection circuit detects the motion of an image in the television signal by utilizing the correlation between signals of the television signal to be detected. The inter-field motion detection circuit detects the motion of an image in the television signal using the correlation between signals of the television signal.

The motion detection control circuit fetches a detection output from the inter-frame motion detection circuit, and detects a difference between the detection output, a field delay output obtained by delaying the detection output by one field, and one line of the detection output. Is used to determine the mixing condition in the motion signal mixing circuit and instruct the motion signal mixing circuit.

The motion signal mixing circuit takes in the detection output from the inter-frame motion detection circuit and the detection output from the inter-field motion detection circuit, and mixes them according to the mixing conditions specified by the motion detection control circuit. The result is output as a motion detection output. As a result, it is possible to improve erroneous detection of a motion that has occurred in a fast-moving video. At this time, there is no increase in the omission of motion detection.

[0031]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing one embodiment of the present invention. In the figure, 101 is an input terminal, 102 is an inter-frame motion detection circuit, 103 is an inter-field motion detection circuit, 104 is a motion detection control circuit, 105 is a motion signal mixing circuit, and 106 is an output terminal.

In addition, 107 is a frame memory, 10
8 is a field memory, 109 is a line memory, 11
0, 111 and 112 are subtraction circuits, 113 and 11 respectively.
5 is an LPF (low-pass filter), 114 and 1 respectively.
Reference numerals 16 and 117 denote absolute value circuits (ABS), respectively.

The television signal input to the input terminal 101 is a television signal to be subjected to motion detection. The television signal is an NTSC composite color television signal (hereinafter simply referred to as a television signal). ) Will be described as an example.

The television signal input from the input terminal 101 is stored in the frame memory 107 for one frame period (5
25H) Delay and output. Thereafter, the subtraction circuit 110 subtracts the television signal from the input terminal 101 and the television signal output from the frame memory 107 to obtain an inter-frame difference signal. Then, in order to remove the color signal component whose phase is inverted between frames, the color signal band is limited by the LPF 113 for the inter-frame difference signal.

Then, the absolute value circuit 114 removes the positive and negative polarities of the difference signal, and outputs the inter-frame motion signal EF.
Output as Further, the television signal input from the input terminal 101 is output with a delay of one field period (262H) in the field memory 108. Further, the output is delayed by one line period (1H) in the line memory 109.

Thereafter, in the subtraction circuit 111, the television signal from the input terminal 101 and the line memory 109
Is subtracted from the television signal output from the above to obtain an inter-field difference signal. Then, in order to remove a color signal component whose phase is inverted between 263H, the LPF 115 limits the color signal band for the inter-field difference signal. Then, the absolute value circuit 116 removes the positive and negative polarities of the difference signal and outputs the difference signal as the inter-field motion signal DF.

The subtraction circuit 112 subtracts the television signal input from the input terminal 101 from the television signal output from the field memory 108 to obtain an inter-field difference signal. Thereafter, the absolute value circuit 117 removes the positive and negative polarities of the difference signal, and outputs the difference signal as the inter-field motion signal HF.

FIG. 4 shows the motion detection control circuit 1 in FIG.
FIG. 4 is a block diagram showing the details of the embodiment 04. The motion detection control circuit 104 will be specifically described with reference to FIG. In this circuit, the control signal of the motion signal mixing circuit 105 of FIG. 1 is generated according to the inter-frame motion signal detected one field before (262H and 263H), one line before and the original signal.

In FIG. 4, reference numeral 401 denotes an input terminal;
Is a field memory (262H), 403 and 404 are line memories, 405 is a subtraction circuit, 406 is an absolute value circuit, 407 is a mixing condition determination circuit, and 408 is an output terminal.

The input terminal 401 receives an inter-frame motion signal EF obtained by the inter-frame motion detection circuit 102. The field memory 402 stores the inter-frame motion signal E
F is delayed by one field period (262H), and an inter-frame motion signal GH is output. Further, the line memory 403
Delays one line period (1H), and outputs an inter-frame motion signal CD.

The inter-frame motion signal EF input from the input terminal 401 is delayed by one line period (1H) in the line memory 404 and output. After that, the subtraction circuit 405
, The inter-frame motion signal EF and the line memory 40
4 is subtracted from the output signal. Then, the absolute value circuit 406 removes the positive and negative polarities of the difference signal and outputs an edge signal of the inter-frame motion signal.

In the mixing condition determination circuit 407, for example, as shown in Table 1 below, the inter-frame motion signals CD, GH, E
F and four control signals (S1 to S4) selected in accordance with a combination of edge signals output from the absolute value circuit 406.
4) is output from the output terminal 408.

[0043]

[Table 1]

The threshold (threshold) for determining that the inter-frame motion signals CD and GH have motion is α, the threshold for determining that EF has motion is β, and the edge signal of the inter-frame motion signal is determined to have edge. Threshold to γ
When, for example, according to the motion signal between each frame,
The control signals (S1 to S4) for controlling the mixing process in the motion signal mixing circuit 105 are set as follows.

When CD ≧ α, GH ≧ α, EF ≧ β, the control signal S1 is output. When CD ≧ α, GH ≧ α, and EF <β, the control signal S2 is output.

When CD ≧ α and GH <α, the control signal S3
Is output. When CD <α, GH ≧ α, the control signal S4 is output.

When CD <α, GH <α, EF ≧ β, the control signal S1 is output. When CD <α, GH <α, EF <β, the control signal S2 is output.

When the edge signal of the inter-frame motion signal ≧ γ, the control signal S1 is output. Note that the values of the thresholds α, β, and γ in the present embodiment may be about 32/255.

FIG. 5 shows the motion signal mixing circuit 1 in FIG.
It is a block diagram which shows the specific example of 05. The details of the motion signal mixing circuit 105 will be described with reference to FIG. In this circuit, four types of motion signals generated by mixing the inter-frame motion signal and the inter-field motion signal in accordance with, for example, the control signals (S1 to S4) generated by the motion detection control circuit 104. One of them is selected and output as a motion signal.

In FIG. 5, reference numeral 501 denotes an inter-frame motion signal (EF) input terminal, and 502 denotes an inter-frame motion signal (263).
H) a motion signal (DF) input terminal; 503, an inter-field (262H) motion signal (HF) input terminal;
5, 506 are adder circuits, 507, 508, 50, respectively.
9 is a coefficient circuit, 510 is a selection circuit, 511 is a mixed control signal input terminal, and 512 is a motion signal output terminal.

The inter-frame motion signal input terminal 501 has
An inter-frame motion signal EF obtained by the inter-frame motion detection circuit 102 is input. The inter-field (263H) motion signal input terminal 502 receives an inter-field motion signal DF obtained by the inter-field motion detection circuit 103. Inter-field (262H) motion signal input terminal 503
, An inter-field motion signal HF obtained by the inter-field motion detection circuit 103 is input.

The addition circuit 504 and the coefficient circuit 507
The sum of the inter-frame motion signal EF and the inter-field motion signal DF is multiplied by a coefficient k1 and output. The addition circuit 505 and the coefficient circuit 508 multiply the sum of the inter-frame motion signal EF and the inter-field motion signal HF by k2 and output the result. The addition circuit 506 and the coefficient circuit 509 calculate the sum of the inter-field motion signal DF and the inter-field motion signal HF by a coefficient k.
Output three times.

In the selection circuit 510, as shown in Table 2 below, for example, control signals (S1 to S1) input from a mixed control signal input terminal 511 created by the motion detection control circuit 104 are input.
4), an inter-frame motion signal EF and a coefficient circuit 5
07, the output signal of the coefficient circuit 508, and the output signal of the coefficient circuit 509 are selected and output to the motion signal output terminal 512.

[0054]

[Table 2]

That is, as shown in Table 2, in the case of the control signal S1, the inter-frame motion signal EF is output. In the case of the control signal S2, k3 (D
F + HF). In the case of the control signal S3, k1 (DF + EF) which is the output of the coefficient circuit 507 is output. In the case of the control signal S4, k2 which is the output of the coefficient circuit 508
(HF + EF) is output.

As an example of the coefficient, k1 = k
2 = k3 = 0.5. In this case, each output signal of the adder circuits 504, 505 and 506 is shifted by 1 bit to the lower side and multiplied by 0.5, so that the coefficient circuit is omitted. There is a merit that can be done.

Next, the motion detection circuit described above (FIG. 1)
The motion detection operation will be described with reference to FIG.
FIG. 6 is a scanning line structure diagram showing a motion detection operation by the motion detection circuit of the present invention. First, the operation of the inter-frame motion detection circuit 102 in FIG. 1 will be described.

In FIG. 6, the horizontal direction indicates time (field), and the vertical direction indicates the vertical direction of the screen. Assume that the pixel of interest is F in n fields. At this time, the television signal delayed by 525H obtained from the frame memory 107 in FIG. 1 is the pixel E in the (n-2) field.
Here, the inter-frame motion signal EF for the pixel F is obtained by the subtraction circuit 110, the LPF 113 and the absolute value circuit 114 in FIG.

Next, the inter-field motion detecting circuit 1 shown in FIG.
03 will be described. Similar to the inter-frame motion detection, the pixel of interest is F in the n-th field in FIG. At this time, the television signal delayed by 1H obtained from the line memory 109 in FIG. 1 is D in the (n-1) field.

Here, the subtraction circuit 111 and the LPF 1 shown in FIG.
15 and the absolute value circuit 116, an inter-field motion signal DF for the pixel F is obtained. Field memory 1
The television signal delayed by 262H obtained from 08 is H in (n-1) fields. Here, the inter-field motion signal HF for the pixel F is obtained by the subtraction circuit 112 and the absolute value circuit 117 of FIG.

Next, the operation of the motion detection control circuit 104 of FIG. 1 will be described. Similarly, the pixel of interest is n in FIG.
Let it be F in the field. At this time, the 262H-delayed inter-frame motion signal obtained from the field memory 402 in FIG. 4 includes the pixel G of the (n-3) field and the pixel G of the (n-3) field.
This is an inter-frame motion signal GH between the pixel H of the field.

The 263H-delayed interframe motion signal obtained from the line memory 403 in FIG. 4 is a frame between the pixel C in the (n-3) field and the pixel D in the (n-1) field in FIG. This is the inter motion signal CD. further,
The 1H-delayed inter-frame motion signal obtained from the line memory 404 in FIG. 4 is an inter-frame motion signal AB between the pixel A in the (n-2) field and the pixel B in the n field.

The subtraction circuit 405 and the absolute value circuit 4 of FIG.
06, an edge signal of the inter-frame motion signal at the pixel F is obtained. For example, as shown in Table 1, the mixing condition determining circuit 407 generates the inter-frame motion signals CD, GH, and EF.
And a control signal corresponding to the combination of the edge signal is output from an output terminal 408.

Next, the result of detection of a motion signal by the motion detection circuit of the present invention will be described with reference to FIG. FIG.
FIG. 7 is a diagram illustrating a scanning line structure and a detection result of a motion signal similar to FIG. 3 described above.

In FIG. 7A, the horizontal direction indicates time (field), and the vertical direction indicates the vertical direction of the screen. A black-level object is displayed in a white-level background in two fields from the bottom to the top of the screen. The image which moved by 5 lines with the lapse of time is shown. The black squares indicate black level signals (scan lines) representing an object, and the white squares indicate white level signals (scan lines) representing a background.

FIGS. 7B, 7C and 7D show the inter-frame motion detection circuit 102 when focusing on n fields.
Shows the inter-frame motion signals EF, CD, and GH detected by. The black circles represent moving images, and the white circles represent inter-frame motion signals determined to be still images. It can be seen that in the inter-frame motion signal shown in FIG. 7D, the motion of the pixels P and Q is missed.

Similarly, FIGS. 7E and 7F show inter-field motion signals DF and HF detected by the inter-field motion detection circuit 103 when focusing on n fields. FIG. 7G shows an edge signal of the inter-frame motion signal detected by the motion detection control circuit 104 when focusing on n fields. The black circles represent the edge portions and the white circles represent the edge signals determined to be the flat portions.

FIG. 7H shows a motion signal mixed and output in response to a control signal in n fields as shown in Table 2, for example. Black circles represent motion signals, and white circles represent motion signals determined to be still images. Black triangles represent motion signals obtained by averaging with and without motion.

As a result, according to the present embodiment, as compared with FIG. 3E, the detection of the motion at the pixel S, which is a problem, and the detection at the pixels T, U, V It can be seen that there is an effect that false detection is improved.

On the other hand, in (h) of FIG. 7, the motion is missed in the pixel P (indicated by a white circle).
Even if Y / C separation processing for a still image using the pixel X is performed on the image data, since the frame correlation is maintained, no dot disturbance or cross color occurs, and no adverse effect occurs.

The control signals output from the motion detection control circuit 104 in this embodiment are not limited to those shown in Table 1. A plurality of types of control signals can be created according to a combination including the level of the inter-frame motion signal or the level of the edge signal.

The mixing process performed by the motion signal mixing circuit 105 in this embodiment is not limited to the one described in Table 2. Depending on the level of the inter-frame motion signal and the inter-field motion signal, a plurality of types of mixing processes including non-linear processes such as a maximum value selection process and a minimum value selection can be performed in addition to the two-input addition process and the three-input addition process. Things.

Next, another embodiment of the present invention will be described with reference to FIG. A distinctive feature of the present embodiment is that the inter-frame motion detection circuit and the inter-field motion detection circuit are integrated so as to serve as a field memory.

FIG. 8 is a block diagram showing another embodiment of the present invention. In the figure, reference numeral 801 denotes an input terminal;
2, 804 are field memories, 803 are line memories, 805, 806, 807 are subtraction circuits, 808, 809 are LPFs, 810, 81, respectively.
Reference numerals 1 and 812 denote absolute value circuits, and 813 denotes an output terminal.

The television signal input to the input terminal 801 will be described using an NTSC composite color television signal as an example. The television signal input from the input terminal 801 is stored in a field memory 802.
Output one field period (262H).

Further, the output is delayed by one line period (1H) in the line memory 803. Further, the data is output after being delayed by one field period (262H) in the field memory 804. Thereafter, in the subtraction circuit 805, the television signal from the input terminal 801 and the field memory 80
4 is subtracted from the output television signal to obtain an inter-frame difference signal.

Then, in order to remove a color signal component whose phase is inverted between frames, the band of the color signal is limited by the LPF 808 with respect to the inter-frame difference signal. Then, the absolute value circuit 810 removes the positive and negative polarities of the difference signal and outputs the difference signal as the inter-frame motion signal EF.

The subtraction circuit 806 subtracts the television signal from the input terminal 801 and the television signal output from the line memory 803 to obtain an inter-field difference signal. Then, in order to remove the color signal component whose phase is inverted between the frames (263H), the band of the color signal is limited by the LPF 809 with respect to the inter-field difference signal. Then, the absolute value circuit 811 removes the positive and negative polarities of the difference signal and outputs the difference signal as the inter-field motion signal DF.

In the subtraction circuit 807, the television signal from the input terminal 801 and the field memory 80
2 is subtracted from the output television signal to obtain an inter-field difference signal. Then, the absolute value circuit 812 removes the positive and negative polarities of the inter-field difference signal,
It is output as the inter-field motion signal HF.

The motion detection control circuit 104 and the motion signal mixing circuit 105 perform the same operation as that of the embodiment shown in FIG. In the above-described embodiment, the field memory required for the inter-field motion detection is configured to be shared with the memory used for the inter-frame motion detection.
There is also an effect that the memory capacity can be saved.

[0081]

According to the present invention, in the motion detection of an image, a field of a motion signal detected between frames is selected from a plurality of motion signals generated by mixing inter-field motion signals in addition to inter-frame motion signals. By selecting and outputting an appropriate one using the correlation and the line correlation, there is an effect that the motion of a fast-moving image can be correctly detected. In addition, since a highly accurate motion signal can be generated, there is an effect that appropriate control of motion adaptive signal processing can be performed.

[Brief description of the drawings]

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

FIG. 2 is a block diagram showing a conventional motion detection circuit.

FIG. 3 is a scanning line structure diagram showing a result of motion detection by a conventional motion detection circuit.

FIG. 4 is a block diagram illustrating details of a motion detection control circuit 104 in FIG. 1;

FIG. 5 is a block diagram showing details of a motion signal mixing circuit 105 of FIG. 1;

FIG. 6 is a scanning line structure diagram showing an operation of motion detection by the motion detection circuit of the present invention.

FIG. 7 is a scanning line structure diagram showing a result of motion detection by the motion detection circuit of the present invention.

FIG. 8 is a block diagram showing another embodiment of the present invention.

[Explanation of symbols]

102: inter-frame motion detection circuit, 103: inter-field motion detection circuit, 104: motion detection control circuit, 105:
Motion signal mixing circuit.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Noboru Kojima 292 Yoshidacho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside the Hitachi Media Research Laboratory, Inc. (72) Kentaro Teranishi 292 Yoshidacho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture (56) References JP-A-4-29488 (JP, A) JP-A-61-274492 (JP, A) JP-A-61-274493 (JP, A) JP 60-57792 (JP, A) JP-A-62-237879 (JP, A) JP-A-2-223288 (JP, A) (58) Fields studied (Int. Cl. ⁷ , DB name) H04N 11/00 -11/24 H04N 9/64-9/78 H04N 7/00

Claims (4)

(57) [Claims] 1. A motion detecting circuit for receiving a television signal, detecting presence or absence of motion of an image in the inputted television signal, and outputting the motion signal, wherein a difference between frames of the input television signal is obtained. An inter-frame motion detection circuit for detecting the presence or absence of an image motion from an inter-frame difference signal, and an inter-field motion detection circuit for detecting the presence or absence of an image motion from an inter-field difference signal obtained by taking a difference between fields of an input television signal A motion signal mixing circuit that captures a detection output from the inter-frame motion detection circuit and a detection output from the inter-field motion detection circuit, and outputs a mixed result as a motion detection output; A detection output from the circuit, the detection output; a field delay output obtained by delaying the detection output by one field; A motion detection control circuit that determines a mixing condition in the motion signal mixing circuit using the inter-line difference signal obtained by taking a difference between one line of force and instructs the motion signal mixing circuit. Motion detection circuit. 2. The motion detecting circuit according to claim 1, wherein the inter-field motion detecting circuit captures and delays an input television signal and outputs the delayed signal, and captures and delays an output signal of the field memory. A line memory for output, a first subtraction circuit for performing subtraction between an input television signal and an output signal of the line memory, and a first subtraction circuit for performing subtraction between an input television signal and an output signal of the field memory. 2, a low-pass filter that removes and outputs a color signal component included in an output signal of the first subtraction circuit, and a first absolute value that takes the absolute value of the output signal of the low-pass filter and outputs the absolute value A second absolute value circuit for taking an absolute value of an output signal of the second subtraction circuit and outputting the result. Motion detection circuit, characterized in that the inter-field motion detection circuit for outputting an output of the second absolute value circuit as inter-field motion detection output. 3. The motion detection circuit according to claim 1, wherein the motion detection control circuit captures an output of the inter-frame motion detection circuit, delays the output, and outputs the output of the field memory. A first line memory for capturing and delaying the output, a second line memory for capturing and delaying the output of the inter-frame motion detection circuit, an output of the inter-frame motion detection circuit, and the second line memory A subtraction circuit for performing subtraction between the output of the first line memory, an output of the first line memory, an output of the field memory, and an output of the frame. The output of the inter-motion detection circuit and the output of the absolute value circuit are used to determine a mixing condition in the motion signal mixing circuit and instruct the motion signal mixing circuit. Motion detection circuit, wherein the mixing condition determining circuit, to be made of that. 4. The motion detection circuit according to claim 2, wherein the motion signal mixing circuit includes an output (EF) of the inter-frame motion detection circuit and a first absolute value in the inter-field motion detection circuit. The output (DF) of the value circuit and the output (HF) of the second absolute value circuit and the output of the motion detection control circuit are fetched, and the fetched output (EF) of the inter-frame motion detection circuit
And an output (DF) of a first absolute value circuit in the inter-field motion detecting circuit.
(4) a second adder for adding the fetched output (EF) of the inter-frame motion detection circuit and the output (HF) of the second absolute value circuit in the inter-field motion detection circuit; ), A third adder circuit (506) for adding the fetched output (DF) of the first absolute value circuit and the output (HF) of the second absolute value circuit in the inter-field motion detecting circuit. A first coefficient circuit for multiplying the output of the first adder circuit (504) by a coefficient k1, and a second coefficient circuit for multiplying the output of the second adder circuit (505) by a coefficient k2. (508) and a third coefficient circuit (509) for multiplying the output of the third adder circuit (506) by a coefficient k3.
And an output (EF) of the inter-frame motion detection circuit according to a control signal which is a captured output of the motion detection control circuit.
And an output of the first coefficient circuit, an output of the second coefficient circuit, and an output of the third coefficient circuit. Motion detection circuit.