METHOD OF COMPENSATING FOR GEOMETRICAL NOISE OF A MATRIX PHOTODETECTOR Russian patent published in 2020 - IPC G06T5/00 G06T7/80 H04N5/357 

FIELD: computer equipment.

SUBSTANCE: invention relates to the computer equipment. Method includes preliminary calibration of geometric noise with minimum exposure time of photodetector t_min by alternating uniform irradiation of elements of photodetector matrix from source with low and high radiation level, digital storage of brightness values of image elements Y₁ and Y₂ for low and high irradiation, respectively, calculating the average value m₁ and m₂ brightness of image elements Y₁ and Y₂, respectively, setting at calibration stage maximum exposure time t_max at a low level of uniform irradiation of the photodetector and digital storage of the obtained brightness values of the image elements Y_max, calculation immediately before informative illumination of coefficient a=(t-t_min)/(t_max-t_min) for photoreceiver set exposure time t within t_min≤t≤t_max, calculating brightness values of reference image elements Y₀ by formula Y₀=aX₂+(1-a)X₁ and its average brightness m₀=am₂+(1-a)m₁, calculation of compensation coefficients K by formula K=(Y₂-Y₁)/(m₂-m₁), obtaining, during informative irradiation, brightness values of image elements Y and generating output digital brightness values X by formula X=(Y-Y₁)/K+m₀. Values of brightness of elements of reference image Y₀ and values of coefficients K are calculated directly with informative radiation. To calculate Y₀ receiving X₂=Y_max, X₁=Y₁, and to calculate compensation coefficients K and output digital values of brightness X is Y₁=Y₀, m₁=m₀. Generation of output digital values of brightness X is carried out in process of information illumination by general formula: X=(m₂-m₀)[Y-aY_max-(1-a)Y₁]/[(Y₂-aY_max-(1-a)Y₁)]+m₀.

EFFECT: technical result consists in reduction of hardware costs for required memory for storage of reference images and compensation coefficients obtained during calibration.

1 cl, 1 dwg