JPS59110286A - Improving method of video due to defective channel - Google Patents

Abstract

PURPOSE:To output a video signal having no deteriorated characteristics by writing address signals which correspond to normal channels before and after a defective channel previously in an ROM so that those address signals are outputted when a read address signal corresponding to the defective channel is inputted. CONSTITUTION:The difference from a conventional device is the way of generating a read address signal when a signal obtained by digitizing an infrared-ray video signal is read out. When the ROM11 is read by an address signal written in the inferior S/N ratio infrared-ray detecting element of the device, addresses are written in the ROM11 previously so that normal channels before and after the defective element are read out. Consequently, when the read signal is inputted from a counter 8 to the ROM11, a signal written in a normal channel is read out of the ROM11. Therefore, the video which is almost free of deterioration in characteristics is obtained.

Description

Detailed Description of the Invention (a) Technical Field of the Invention The present invention relates to a method for improving an image produced by a defective infrared detection element of a multi-element type external optical imaging device, which uses a defective channel to obtain an image with almost no deterioration. Concerning how to improve images.

(b) Background of the technology Infrared imaging devices are used to measure the temperature of the surface of an object, and their purpose is to determine the temperature distribution on the surface of an object by measuring the intensity of infrared rays emitted from the object. be.

In order to know the temperature distribution, the object is scanned, etc.
The obtained infrared rays are focused on a point where an infrared sensing element is placed (by condensing, etc.), and the infrared sensing element detects the temperature of the object using the focused light and converts it into an electrical signal. After digitizing and storing the data, a TV video signal is created by scan conversion and displayed on a TV monitor to determine the temperature distribution at the edge of the object. ○In order to shorten the surface scanning time, a large number of infrared detection elements are used. There is a multi-element optical external imaging device.

(C) Prior art and problems The large number of infrared sensing elements in a multi-element external optical imaging device has S
/N (signal-to-noise ratio) may be included. If this infrared detection element with poor S/N is used, the image will be unclear.

For this reason, the following method has conventionally been adopted.

FIG. 1 is a block diagram showing the circuit configuration of the main parts of a conventional multi-element external optical imaging device.

In the figure, 1 1 to 1-n are infrared detection elements, 2-1 to 2-N
3 is an amplifier, 3 is an analog switch, 4 is an analog/digital converter (hereinafter referred to as an A/D converter), 5 is a scan conversion RAM (random access memory input), 6 is a digital/analog converter (hereinafter referred to as a D/D converter), and 5 is a scan conversion RAM (random access memory input). 7 is a read/write switch (hereinafter referred to as R/W switch), 8 is a counter, 9 is a synchronization signal generator that generates a synchronization signal to synchronize the operation of each part, and 10 is a scanning The converter is shown.

To explain the operation, a large number of infrared sensing elements 1-1 to 1-
The electrical signals obtained by n are amplified by amplifiers 2-1 to 2-n and input to the analog switch 3.

The input electrical signals are sequentially switched by an analog switch 3, subjected to analog-to-digital conversion by an A/D converter 4 of a scan converter 10, and then inputted to a RAM 5. At this time R/
The W switch 7 outputs the write address and write signal from the counter 8, and writes the digital signal input L7 into the RAM 5. Next, the digital signal written in the RAM 5 is outputted as a read address and a read signal from the υ counter 8 by the R/W switch 7, and then in series from the RAM 5 according to the TV synchronization signal from the synchronization signal generator 9. The signals are read out in the order in which they were written, digital-to-analog converted by the D/A converter 6, and output as a television video signal. In this way, the scan converter 1o scan-converts the infrared video signal from the scanning system so that it is synchronized with the television video signal. If, for example, the infrared sensing element 1-2 has a poor S/N ratio, the input of the amplifier 2-2 which inputs its output is inputted, and the output of the adjacent infrared sensing element 1-3, for example, is inputted. Connect the input of amplifier 2-3 with a strap wire, and
The low level signal from the infrared detection element 1-2 with bad /N and the high level signal from the normal infrared detection element 1-3 are input to the amplifier 2-2 to make the image clear. There is. Even in this case, the position of the subject detected by the infrared detection element with poor S/N is not significantly different from the position of the subject detected by the adjacent infrared detection element, so a substantially normal image can be obtained. However, in this method, amplifiers 1-2 and 1
-3 input impedance changes, amplifiers 1-2 and 1
-3 frequency characteristics are deteriorated and the dynamic range is narrow, which has the drawback of deteriorating the image characteristics.

(d) Purpose of the Invention In view of the above-mentioned drawbacks, the purpose of the present invention is to provide a method for improving video using a defective channel in which video characteristics hardly deteriorate even if there is an infrared detection element with poor S/N ratio. .

(e) Structure of the Invention In order to achieve the above object, the present invention provides a continuous address signal on the output side of a read address signal of a counter that generates an address signal of a scan conversion memory of a multi-element type external optical imaging device. is input, and a dedicated memory for outputting a read address signal is provided, and when a read address signal corresponding to a defective channel is input to the continuous read only memory, a read address signal corresponding to the previous and succeeding normal channels is outputted in advance. The read address signal corresponding to the defective channel outputs the address signal corresponding to the normal channel before or after the input, and the scan conversion memory then outputs the address signal corresponding to the normal channel before or after the read address signal corresponding to the defective channel. , the infrared video signal of the previous or subsequent normal channel is read out.

(f) Examples of the invention An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is a block diagram showing the circuit configuration of the address signal generating section of the scan conversion memory according to the embodiment of the present invention.

Components in the figure that have the same functions as those in FIG. 1 are indicated by the same symbols.

11 is a read-only memory (hereinafter referred to as ROM).

Although FIG. 2 shows only the address signal generating section of the scan conversion memory of the multi-element external optical imaging device, the other circuit configuration is the same as that of FIG. 1.

The difference in FIG. 2 from the case in FIG. 1 is the way a read address signal is generated when reading a signal obtained by digitizing an infrared video signal from the scan conversion memory 5 (RAM) in FIG. ROMII is loaded with R in Figure 1 from counter 8.
It is written so that when an address signal to be read from AM5 is input, the same address signal is output. However, S/N
Since the defective channel with the bad infrared detection element is known in advance, when the address signal for reading the signal written in the RAM 5 in FIG. Figure RA
Write in ROMII so as to output an address signal to read the signal written in M5. By doing this, the address signal for reading out the signal written in the RAM 5 in FIG.
When input to the ROM 11, an address signal is output from the output of the ROM II to read out the signal stored in the previous or next normal channel, and an address signal is output from the RAM 5 in FIG. 1 to read the signal written in the previous or next normal channel. A signal is output. Therefore, an image with almost no deterioration in characteristics can be obtained. Naomata 2
Reliability is also improved because there is no need to connect the inputs of two amplifiers with strap wires.

(g) Effects of the Invention As explained in detail above, according to the present invention, even if there is an infrared detection element with a poor S/N ratio, the characteristics of the image hardly deteriorate and the linearity is also improved. There is.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the circuit configuration of the main parts of a conventional multi-element infrared imaging device, and FIG. 2 is a block diagram showing the circuit configuration of the address signal generation section of the scan conversion memory according to the embodiment of the present invention. In a certain 1° diagram, 1-1 to 1-n are infrared detection elements, 2-1 to 2-n are amplifiers, 3 is an analog switch,
4 is an analog/digital converter, 5 is a scan conversion memory, 6 is a digital/analog converter, 7 is a read/write switch, 8 is a counter, 9 is a synchronization signal generator, 10
11 indicates a scan conversion unit, and 11 indicates a read-only memory.

Claims (1)

[Claims] A read-only device that inputs the read address signal to the output side of the read address signal of a counter that generates the address signal of the scan conversion memory of the scan conversion unit of the multi-element external optical imaging device and outputs the read address signal; A defective channel characterized in that a memory is provided, and written in the read-only memory so that when a read address signal corresponding to the defective channel is inputted, a read address signal corresponding to the preceding and succeeding normal channels is outputted. How to improve your footage.