Method and device for detecting dead pixels in an image

Abstract

The invention discloses an image defective pixel detection method and apparatus. The method includes: obtaining an N*M pixel block of an image, arranging all pixel points in the pixel block in sequence to obtain a pixel value sequence, calculating a median of the pixel value sequence, and obtaining a pixel median; determining a specified small pixel value and a specified large pixel value from the pixel value sequence, calculating a first difference, and determining the pixel type of a current pixel point and calculating a second difference according to the relation between the current pixel point and the pixel median; and determining whether the current pixel point is a suspected defective pixel by determining whether the quotient of the second difference and the first difference is greater than a first preset error. The defective pixel is checked based on the attribute of the defective pixel of the image, compared with the conventional defective pixel detection method, the hardware area is reduced, pixel points of the image are checked one by one, more suspected defective pixels can be discovered, and the detection efficiency of the defective pixels is improved.

Description

technical field [0001] The invention relates to the field of computer technology security, in particular to a method and device for detecting bad image pixels. Background technique [0002] With the advancement of science and technology, the resolution of existing camera sensors continues to increase. The previous dead point detection algorithms are mainly aimed at the detection of dead pixels of sensors with small and medium resolutions. For sensors with high resolutions, many algorithms have slow detection speeds and cannot achieve online detection. At the same time, the existing dead point detection method (such as the method based on LUT) needs to occupy MEM and consume chip area. With the continuous improvement of ISP input resolution, its area consumption will increase by dozens of times. At the same time, with the improvement of living standards, people have higher requirements for image quality. The user's eyes are very sensitive to the bright or dark spots on a pic...

AI Technical Summary

Problems solved by technology

[0003] To this end, it is necessary to provide a technical solution for image dead point detection to solve the problems of existing dead point detection algorithms such as chip area consumption, low detection rate of dead points, and inability to meet the needs of large-resolution sensors.

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