SU1202076A1 - Device for compensating additive and multiplicative stray components in video signal - Google Patents

Abstract

DEVICE FOR COMPENSATION OF ADDITIVE AND MULTIPLIKATIVNYHPARAZITNYH component in vidaosigNAPB comprising a memory unit to ffitsientov compensation multiplikativVh hydrochloric moiety whose output is connected to a first input of multiplying the video signal and subtractor characterized in that, in order to simplify the device by avoiding storage unit whith compensation coefficients the additive component, the subtraction unit is made in the form of a constant component exclusion circuit, the input of which is connected to the output of the video multiplication unit Igna whose input is an input device. § O) with Ex.

Description

I

This invention relates to video signal processing and may be used. used to detect and recognize weak signals at the background level.

The aim of the invention is to simplify the device by eliminating the memory block of the additive component compensation coefficients.

The drawing is a block diagram of the device.

The device contains a block 1 pre-processing of the video signal, including, for example, block 2. sampling and storage and analog-to-digital converter 3, video multiplication unit 4, subtraction unit 5, multiplier compensation component memory 6, and a digital-to-analog converter 7.

The device works as follows.

The device is first calibrated. To do this, a multi-element radiation detector (not shown) supplies an optical flux of uniform illumination and determines coefficients inversely proportional to the sensitivity for each element, which are recorded in memory block 6.

/

In the working mode of operation, the video signal samples, as well as during calibration, are converted into the form,;. convenient for carrying out operations on them, in block 1 of video signal preprocessing with the help of

by block 2 sample-storage and analog-to-digital converter 3 to digital form. Next, the transformed video signal samples are multiplied in block 4 by multiplying the video signal by the compensation coefficients of the multiplicative component from block 6 determined during the calibration process.

10 In block 5, the subtraction subtracts the normalized parasitic component, the value of which is determined during the calibration process. Since as block 5

15 the subtraction scheme is used to exclude the constant component, then it is not necessary to determine and memorize the normalized parasitic component. It is automatically subtracted during the operation mode by the circuit.

elimination of constant components. This eliminates the need for additional calibrations of the device when changing the value of the constant

25 background threads.

The operation of the proposed device is based on the fact that after multiplying by coefficients inversely proportional to the multiplicative

30 interference, the additive component is normalized and becomes constant for all video samples in a frame due to the correlation of additive and multiplicative components, which is the case for the prevailing number of multi-element photoreceivers. Next, it performs-: with the conversion of the results of the subtraction to the analogue form in the digital-to-Q channel with the help of the inverter 7.

Claims (1)

DEVICE FOR COMPENSATION OF ADDITIVE AND MULTIPLICATIVE ’PARASITIC COMPONENTS IN THE VIDEO SIGNAL, comprising a memory block of the coefficients of the compensation of the multiplicative component, the output of which is connected to the first input of the video multiplier, and a subtraction block; characterized in that, in order to simplify the device by eliminating the memory block of the coefficients of the compensation of the additive component, the subtraction unit is made in the form of a circuit for eliminating the constant component, the input of which is connected to the output of the video signal multiplication unit, the input of which is the input of the device.