Method and apparatus for compensation of point noise in CMOS imagers

摘要

This invention corrects of white spot noise in an imager. If the brightness value of a pixel is greater than the maximum brightness value of eight surrounding pixels, then the compensated output is this maximum brightness value. If the brightness value of the pixel is less than the maximum brightness value, then no compensation is applied. Alternatively the brightness value of the pixel may be compared with the maximum brightness value plus a threshold value. The invention stores correction values for a few pixels. If a particular pixel has a stored correction value, then this is subtracted from the brightness value of the particular pixel and the maximum brightness correction is applied to this difference. The stored correction value is replaced with the difference between the brightness value of the particular pixel and the maximum brightness value if this difference is greater than the stored correction value.