JPH01318383A - Motion detecting circuit - Google Patents

Abstract

PURPOSE:To correctly detect motion by counting the number of times of occurrence of data detected as motion in a certain area and discriminating it based on the counted result whether data is true or not. CONSTITUTION:When a television signal is applied to an input terminal 1, motion data '1' is outputted from a motion detecting circuit 10 when a moving picture is discriminated independently of the presence or the absence of error due to mixture of noise or the like, and motion data '0' is outputted from the circuit 10 when a still picture is discriminated, and the number of times of occurrence of motion data in a set area is counted by a counting circuit 20, and the counted result is applied to a setting circuit 30, and the circuit 30 outputs '1' when the number of times of occurrence is equal to or larger than a threshold, and the circuit 30 outputs '0' when the number of times of occurrence is smaller than the threshold. Thus, erroneous data generated as an isolated point by mixture of noise or the like is corrected to accurately extract motion information.

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 ART Conventionally, a motion detection method for a television signal involves determining the absolute value of the difference in signal level of corresponding pixels between a current frame image and an image one frame period ago in a television signal. It detected movements of different sizes.

FIG. 9 is an example of a conventionally known motion detection circuit for 1dNTSC color television signals.

(Japanese Unexamined Patent Publication No. 58-130685) An NTSC color television signal input to an input terminal 1 is delayed by one frame period by a frame memory (525H memory) 2, and an interframe difference signal is obtained by a subtraction circuit 3. This is input to a low pass filter (LPF) 4 to obtain motion information of low frequency components. Next, the output of the LPF 4 is input to the absolute value circuit 6 and the absolute value of the signal is taken, and then in the comparator circuit 6, it is compared with a threshold value. If not, it is determined that the image is a still image, and as a result of the determination, motion data of "1" if it is a moving image and 0" if it is a still image is output from the output terminal 7.

Problems to be Solved by the Invention However, the above-described motion detection method has a problem in that it is not possible to correct motion information that is erroneously obtained due to the inclusion of noise or the like.

Therefore, in view of the above-mentioned problems, the present invention provides accurate movement 3.
-7 This provides a motion detection circuit that can extract information.

Means for Solving the Problems In order to solve the above problems, the motion detection circuit of the present invention has the following features:
A motion detecting means for detecting the motion of a subject in a video signal and generating motion data; a means for counting the number of occurrences of the motion data within an arbitrary area; and means for forcibly setting the motion data.

Function The present invention uses the above-described configuration to count the number of occurrences of motion data within an arbitrary area, and sets correct motion data based on the counting results. Can correct incorrect data.

Embodiment Hereinafter, a motion detection circuit according to an embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, numeral 10 is, for example, the motion detection circuit shown in the conventional example shown in FIG. 9, and any motion detection circuit may be used as long as it is a motion detection circuit. 20 is a counting circuit that counts the number of occurrences of data, and 30 is a setting circuit that sets motion data of the pixel of interest.

As explained in the conventional example, when a television signal is applied to the input terminal 1 in FIG.
11I, if it is determined that the image is a still image, motion data of 0'' is output from the motion detection circuit 10.Next, the number of occurrences of motion data within the set area is counted in the counting circuit 2o. The counting circuit 2o is composed of, for example, a circuit as shown in Fig. 2. In Fig. 2, 21 is an input terminal;
2 is an output terminal, 23 is an adder, and 24a and b are one-pixel delay devices. The motion data of points a, b, and c in Figure 2 are shown in Figure 3 a.
, b, and c. In other words, adder 2
3, the number of occurrences of motion data in an area of three pixels in the horizontal direction (the number of occurrences of 1°) is obtained.

The counting results are then applied to the setting circuit 30.

5 pages/' The setting circuit 30 is configured using a comparator as shown in FIG. 4, and outputs 1°'' when the number of occurrences is above the threshold value, and outputs II 011 when the number of occurrences is less than the threshold value. do.

For example, as the output 11 of the motion detection circuit 1o, as shown in FIG.
Suppose that we have obtained the data shown in .

Here, in FIG. 5a, the data shown in A and B are data that have been mistakenly determined to be 1'' or o'''' due to the contamination of noise, etc.The data shown in FIG. 5a is shown in FIG. When added to the counting circuit shown in FIG. The output will be as shown in Figure 5C.In this way, the data that was incorrectly determined to be °1'' or 0'' as shown in Figure 5A and A and B will become as shown in Figure 5C. Correctly corrected.

FIG. 6 shows another example of the configuration of the counting circuit 2o in FIG. In FIG. 6, 21 is an input terminal, 22 is an output terminal, 23 is an adder, 24a and 24b are 16 vane line delayers, and 25a-f are 1-pixel delayers.

The motion data of M1 to M9 in FIG. 6 is the same as the motion data of M1 to M9 in FIG.
This corresponds to motion data of 9 pixels.

31i in the horizontal direction with the configuration shown in Figure 6! i
The number of occurrences of motion data (the number of occurrences of "1") in a total of nine pixels (3×3) area of i pixels and three lines in the vertical direction is counted by the adder 23 and output from the output terminal 22.

For example, suppose that data as shown in FIG. 8a is obtained as the motion data output of the motion detection circuit 1o in FIG. At this time, if M5 is the pixel of interest, the output of the counting circuit 2o is the result shown in FIG. 8, which is the result of counting the motion data of an area of 9 pixels in total, 3 pixels in the horizontal direction and 3 pixels in the vertical direction. As a result, if the motion data is set by setting the multi-threshold value to, for example, 3', the result shown in FIG. 8C is obtained.

Note that the area to be counted is not limited to this, and may be arbitrarily set using a 1-line delay device and a 1-pixel delay. It is also possible to use a three-dimensional domain in which pixels in the time direction are counted using a one-field delay device.

Effects of the Invention As explained in detail above, according to the present invention, the truth or falsity of the data is determined based on the result of counting the number of occurrences of data detected as motion within a certain area.
Data containing errors caused by noise etc. are corrected and movement can be detected correctly.

[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 data generation frequency counting circuit, FIG. 3 is a schematic diagram showing a counting area, and FIG. 4 is a configuration of a determination circuit. 6 is a schematic diagram showing data for detailed explanation of the present invention, FIG. 6 is another block diagram of the data generation frequency counting circuit, FIG. 7 is a schematic diagram showing the counting area, and FIG. This figure is a diagram showing data for explaining the operation of the counting circuit shown in FIG. 6, and FIG. 9 is a block diagram showing a conventional example of a motion detection circuit. 10... Motion detection circuit, 2o... Data generation number counting circuit, 30... Judgment circuit. Name of agent: Patent attorney Toshio Nakao and 1 other person → Shabashi (N faction + 12a)

Claims (1)

[Claims] a motion detection means for detecting the motion of a subject in a video signal and generating motion data; a means for counting the number of occurrences of the motion data within a region around the pixel of interest; and based on the counting result of the counting means, A motion detection circuit comprising means for forcibly setting motion data for the pixel of interest.