JPS63314988A - Video rate color extracting device - Google Patents

Abstract

PURPOSE:To enable an image obtained from a TV camera to be precessed with a video rate by A/D-converting R, G and B signals obtained from a color TV image, table-converting them with a table previously given and extracting a color previously specified from the image. CONSTITUTION:Data stored in memory circuits 6-8 takes an R value in the memory 6 outputting the R signal when a value indicating the color operated by using the digital R component, G component and B component of a signal from the TV camera is in a specified color area and it takes zero in case of the outside of the area. When the value indicating the color is in the specified color area, it takes G value in the memory 7 outputting the G signal and it takes zero in case of the outside of the area. When the value indicating the color is in the specified color area, it takes a B value in the memory 8 outputting the B signal and it takes zero in case of the outside of the area. Therefore as the R, G and B signals degitized by A/D converter 1-3 are inputted as address and a color exstraction image is generated by table-converting them, the processing by the video rate can be realized.

Description

Detailed Description of the Invention [) Already Required] The present invention is used in the field of video L/G image processing to convert RGB (red, green, blue) signals obtained from a color TV image into an A/D converter. Call out, that digital R, G.

The B signal is table-converted using a table given in advance to extract a pre-specified color from the image.

[Industrial application field]

The present invention allows pixels of a specified color in an image obtained from a TV left camera to be used as a video ray! - relates to a video rate color extraction device for extraction (in real time with respect to a video signal);

This device is used for image synthesis, image processing, unmanned monitoring systems, factory automation systems, etc. based thereon.

[Conventional technology]

゛ As this type of image processing device, a chromakey device using an analog circuit is known. Also, the image signal is A/D
There is also known an apparatus in which the data is converted and processed by software using a frame memory and a digital computer (see FIG. 2).

[Problems to be Solved by the Invention] The above-mentioned chromakey device has problems in that it is not easy to change the designated color, and the device is 4M coarse and expensive.

Those that use a frame memory have the problem that they cannot process at the video rate because they can only handle still images stored in the frame memory from a TV camera.

[Means for solving problems]

The video rate color extraction device of the present invention includes an A/D conversion circuit that A/D converts R-G-B analog signals obtained from a TV camera, and a computer connected to the output of the A/D conversion circuit or externally. A select circuit outputs one of the addresses of , the output from the select circuit is used as an address input, the total 'ff Ph% data is used as a data input, outputs color extraction data during color extraction operation, and is connected during data storage. a memory circuit that stores data from a computer;
It includes an interface circuit for a computer and a D/A conversion circuit for D/A converting the output from the memory circuit.

Then, the data stored in the memory circuit is such that when the value (α) representing the color calculated using the digital R component, G component, and B component of the signal from the TV camera is within the designated color area, the R
The memory that outputs the signal takes the R value and takes zero when outside the area, and when the value representing the color is within the specified color area, the memory that outputs the G signal takes the G value and takes zero when outside the area. , when the value representing the color is within the designated color area, the memory that outputs the B signal takes the B value, and when it is outside the area, it takes the value zero.

[For production]

Using the above-mentioned device, the R, G, and B signals digitized by the A/D converters 1 to 3 are input as addresses, and processed at video rate in order to perform table conversion and generate a color extraction image. becomes possible. Furthermore, by rewriting the contents of the table using a computer, the designated color can be easily changed.

〔Example〕

A block circuit diagram of a video rate color extraction device as an embodiment of the present invention is shown in FIG.

This device includes A/D converters 1.2, 3, selector 4, register 5, memory 6.7.8, D/A converters 9, 10.
11 and a host computer interface 12,
It is connected to a host computer (not shown) via a host computer interface 12.

The A/D converter 1 performs A/D conversion on an R (red) analog TV signal and outputs 6-bit digital data using a given clock. A/D converter 2 is G (green) analog TV
A/D converts the signal and outputs 6-bit digital data using the given clock. The A/D converter 3 is B(
Blue) A/D converts the analog TV signal and outputs 6-bit digital data using the given clock.

Selector 4 uses the outputs of A/D converters 1 to 3 as A input,
The address of the host computer (18 bits) is input as B,
A or B is output by giving a select input from the host computer. For example, the B input is output when rewriting the contents of the memories 6 to 8, and the A input is output during a color extraction operation. The register 5 uses the output from the selector 4 as a data input, and uses the clock as a clock input.

Memories 6 to 8 use the output of register 5 as address input (Ad
d) The signal from the host computer interface 12 is used as chip enable input (cE), the data from the host computer is used as data input (Di), the write enable from the host computer is used as write enable input (WE), and 6 bits of data are output. do. By chip enable given to memories 6 to 8, all memories 6 to 8 are enabled during color extraction operation, and when rewriting the contents of the memory, the chip enable of one of memories 6 to 8 is turned on, and memory 6 to 8 is turned on. Either is enabled.

The D/A converter 9 uses the output of the memory 6 as a data input, the clock as a clock input, and outputs an R analog TV signal. The D/A converter 10 uses the output of the memory 7 as a data input, the clock as a clock input, and outputs a G analog TV signal. The D/A converter 11 uses the output of the memory 8 as a data input, the clock as a clock input, and outputs a B analog TV signal.

The data stored in memory is determined as follows. R, G, and B are the digital R components of the TV signal, respectively;
In the case of a digital G component and a digital B component, the value α representing the color is determined using the above formulas (where S=R+G+B) (0≦β≦π/3). The data stored in memory is specified by a certain color (specified by the range of α above, if you want to extract only red color, 2.9<α<3.4
), when α obtained by (R, G, B) is within the range, the data stored in memory 6 is R1, the data stored in memory 7 is G1, the data stored in memory 8 is B, and if α is outside the range At times, the data stored in the memories 6 to 8 becomes O.

In the above equation, β represents saturation and T H represents the set threshold. For example, the value of α is red (2, 9
<α<3.4) and yellow (3,8<α<4.2).

In this embodiment, an A/D converter, a D/A converter,
It can be a small-scale device because it is configured with a memory for table conversion and an interface with a computer for storing table contents in the memory.

〔Effect of the invention〕

According to the present invention, since color extraction can be performed by table conversion in memory, images obtained from a TV camera can be processed at video rate. Furthermore, by rewriting the contents of the memory table on a connected computer, the designation of the color to be extracted can be easily changed.

[Brief explanation of drawings]

FIG. 1 is a block circuit diagram of a video rate color extraction device as an embodiment of the present invention, and FIG. 2 is a block diagram illustrating the prior art. In the figure, 1.2.3...A/D converter, 4...Selector, 5...Register, 6.
7.8...Memory, 9.10.11...D/A converter, 12...Host computer interface.

Claims (1)

[Claims] In a video rate color extraction device that generates an image at a video rate by extracting specified colors from an image obtained from a TV camera, each of R, G, and B analog signals obtained from the TV camera is A/D conversion circuits (1, 2, 3) that perform A/D conversion; and a selection circuit (1, 2, 3) that outputs either the output of the A/D conversion circuit or the address of an externally connected computer.
4) and a memory circuit which takes the output from the select circuit as an address input, takes the data from the computer as data input, outputs color extraction data during a color extraction operation, and stores data from the connected computer when storing data. (6, 7, 8), an interface circuit (12) for the computer, and a D/A conversion circuit (9, 10, 11) for D/A converting the output from the memory circuit, The data stored in the circuit is that when the value representing the color calculated using the digital R component, G component, and B component of the signal from the TV camera is within the specified color area, the R signal memory circuit (6) stores the R signal.
A video rate color extraction device characterized in that a G value is set in a G signal memory circuit (7), a B value is set in a B signal memory circuit (8), and both are zero when outside the area.