JPH01318380A - Motion detecting circuit - Google Patents

Abstract

PURPOSE:To smoothly connect the boundary between a still picture and a moving picture by counting the number of times of occurrence of motion data in an arbitrary area and setting motion data in three or more levels. CONSTITUTION:An interpolating filter block 10, a motion detecting circuit 20, a counting circuit 30 which counts the number of times of occurrence of motion data in an arbitrary area, and a setting circuit 40 which sets motion data of a noticed picture element are provided. The number of times of occurrence of motion data is counted in a certain area, and motion data is newly set in three or more levels based on the counted result. Thus, erroneous motion data generated as an isolated point by mixture of noise or the like is corrected, and the boundary between the still picture and the moving picture is smoothly connected in three or more levels to obtain a natural picture.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a motion detection circuit that detects the motion of a subject in a video signal.

BACKGROUND OF THE INVENTION One of the problems encountered with current television receivers is line flicker interference. This means that the current receiver is 2 =
This is an interference caused by one-interlace scanning, and in order to remove this interference, a method of sequential scanning using an interpolation filter is used.

In this method, if the same interpolation filter used for still images is used for moving images as well, synchronized image interference will occur due to the temporal lag in the moving images.

Therefore, the movement of the subject in the video signal is detected, and the interpolation filter for still images is used in the case of still images, and the interpolation filter for moving images is used in the case of moving images. It is necessary to perform processing. (This process is called motion adaptive scanning line interpolation.) FIG. 6 shows an example of a conventionally known motion adaptive scanning line interpolation circuit.

In FIG. 6, the signals at points a, b, c, and d correspond to the signals shown in FIG. 7.

In Fig. 6, Y after YC separation input to input terminal 1
The signal is first input to an interpolation filter block 10.

One line delayer 11 inside the interpolation filter block 10
and 262 lines (1) yield) signals corresponding to a, b, and c in FIG. 7 are obtained in the delay device 12. Assuming that Fig. 7 is a signal to be interpolated, in the case of a still image, I = C, and in the case of a moving image, in the adder 13, I = - (a
10b) is interpolated as Interpolation signals for still images and moving images are connected to the switch 14, respectively.

The motion detection block 20 determines whether the image is a still image or a moving image. The motion detection block 20 receives a signal corresponding to the signal shown in FIG. After that, the absolute value circuit 23 takes the absolute value. The difference signal converted into a positive number is sent to a comparator 24.
If it exceeds the threshold, it is determined to be a moving image, and if it does not exceed the threshold, it is determined to be a still image. The switch 14 selects the above-mentioned still image and moving image interpolation signals according to the motion data, and outputs them from the output terminal 2.

Problems to be Solved by the Invention However, in the above-described motion detection method, motion data that is erroneously obtained due to the introduction of noise or the like is output as is and cannot be corrected. Also, motion data has two levels: video/still image, so if you switch the interpolation method accordingly, there will be a large difference in image quality at the boundary between the video and still image on the screen, resulting in an unnatural image near the boundary. There is an issue of becoming.

In view of the above problems, the present invention provides a motion detection circuit that can accurately extract motion information and extract motion data having three or more levels so that the boundary between a moving image and a still image is smoothly connected. be.

Means for Solving the Problems In order to solve the above problems, the motion detection circuit of the present invention detects the movement of a subject in a video signal and detects a "still image" or a video signal.
motion detection means for generating motion data indicating the pixel of interest; a counting means for counting the number of occurrences of the motion data within an arbitrary area around the pixel of interest; and level setting means for setting data at three or more levels.

Function The present invention counts the number of occurrences of motion data within an arbitrary region using the above-described configuration, and based on the counting results, newly calculates three motion data.
Since the movement data is newly set at a level higher than the stage,
Erroneous data generated as isolated points due to the inclusion of noise etc. can be corrected, and the boundaries between still images and moving images are smoothly connected at three or more levels, so a natural image can be obtained.

Embodiment A motion detection circuit according to an embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 1o is an interpolation filter block, 2o is the motion detection circuit of the conventional example shown in FIG. This is the setting circuit for setting.

As explained in the conventional example, the Y signal input to the input terminal 1 in FIG. Diagram a.

Signals corresponding to b and c are obtained. If Fig. 7 is the signal to be interpolated, in the case of a still image I=C; in the case of a moving image, the area near the boundary between the moving image and the still image is processed by the adder 13 as a quasi-moving image;
The adder 15 complements the signal as 1@. In this embodiment, the interpolation method is switched in three stages, but the present invention is not limited to this, and any multi-stage switching of three or more stages may be used.

Further, the interpolation method is not limited to the method used in this embodiment.

Switch 1 is the interpolation signal for video/semi-video/still image.
Connected to input 4.

Furthermore, the Y signal applied to the input terminal 1 is transmitted to the motion detection circuit 20.
added to.

As explained in the conventional example, the motion detection circuit 20 uses, for example, 1111 degrees when it is determined to be a moving image, and 0 when it is determined to be a still image, regardless of whether or not there is an error caused by noise or the like.
Outputs the motion data. Next, the number of occurrences of motion data within the set area is counted in the counting circuit 3o. The counting circuit 20 is composed of, for example, the circuit shown in FIG. In Fig. 2, 33 and 34 are 1-line delay devices,
35a to 3sf are one-pixel delay devices, and 36 is an adder.

M1 to M9 shown in FIG. 2 correspond to the pixel motion data shown in FIG. 3. In other words, the number of occurrences of ``1'' in a total of 9 pixel areas (3×3, 3 pixels in the horizontal direction and 3 pixels in the vertical direction) is obtained at the output terminal 32 of the adder 36. Next, the signal is input to the setting circuit 40, converted into three levels (moving image/semi-moving image/still image), and connected to the switch 14 and the wholesale signal.

The setting circuit 40 is constructed using, for example, a comparator shown in FIG. 43 and 44 are comparators, which output 1" when the input signal (count i1m) exceeds the 1 remainder value set for each, and (threshold 1 minus threshold 2)
Then, as shown in FIG. 5, the conversion characteristic of the setting circuit 40 is that if the input signal (count value) is smaller than the threshold value 1, it is determined to be a still image and outputs "oo'" as the setting value. If the input signal (count value) is larger than threshold 1 and smaller than threshold 2, it is determined that it is a quasi-moving image, and 1o is output as a set value. If the input signal (count value) is larger than the threshold value 2, it is determined that it is a moving image, and 11'' is output as the set value.

Errors caused by noise or the like usually exist as isolated points, so the count values of surrounding pixels are small, and if set according to the characteristics shown in FIG. 5, they will be removed as 'oo'.

The switch 14 selects the supplementary u old signal of 'oo°' for still image, '10' for semi-moving image, and '11' for moving image according to the three-stage setting value from setting circuit 4o.
Output from output terminal 2.

91,7 In this embodiment, a circuit for setting three levels as motion data has been described, but the circuit is not limited to this, and by further connecting comparators in parallel, a circuit with three or more levels can also be used. realizable.

Further, in this embodiment, the setting circuit is realized using a comparator, but a ROM (Read Only Memory) or the like may be used.

Effects of the Invention As explained in detail above, according to the present invention, the number of occurrences of motion data is counted within a certain area, and based on the result, three
Since new motion data is set at a level higher than one level, it is possible to correct erroneous motion data that has occurred as an isolated point due to the incorporation of noise, etc., and the boundary between a still image and a video is smoothly connected at a level higher than three levels, so it is natural. You can get a good image.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, FIG. 2 is a block diagram of a counting circuit, FIG. 3 is a schematic diagram showing a counting area, FIG. 4 is a circuit diagram of a setting circuit, and FIG. 5 is a characteristic 10 diagram showing the conversion characteristics of the setting circuit, FIG. 6 is a block diagram showing the configuration of a conventional motion detection circuit, and FIG. 7 is a schematic diagram showing data for explaining the operation of FIG. 6. It is. 1...Input terminal, 2...Output terminal, 1o...
Interpolation filter block, 2o...Motion/1 detection circuit,
30... Counting circuit, 40... Setting circuit. Name of agent: Patent attorney Toshio Nakao and one other person

Claims (1)

[Claims] a motion detection means for detecting the motion of a subject in a video signal and generating motion data indicating a still image or a moving image; a counting means for counting the number of occurrences of the motion data in an arbitrary area around the pixel of interest; A motion detection circuit comprising: level setting means for setting motion data for the pixel of interest at three or more levels based on the counting results from the means.