Noise reducer for video signals has median filter with low pass filtered output; complementary high pass signal is formed by subtraction of filter inputs with equal transition times

摘要

The noise reducer has a median selector receiving reference image point values, image points vertically or horizontally adjacent to the image point and/or image point values corresponding to the image point in a preceding and/or subsequent image. The filter output is low pass filtered. A complementary high pass signal is formed by subtracting filter input signals with equal transition times and added back to the low pass signal via a Coring stage. The noise reducer has a median selector, to whose inputs are fed reference image point values and at least image points vertically or horizontally adjacent to the image point and/or image point values corresponding to the image point in a preceding and/or subsequent image. The output of the median filter (6) is low pass filtered and a complementary high pass signal is formed by subtraction of input signals of the median filter with equal transition times and added back to the low pass signal via a Coring characteristic. Independent claims are also included for the following: a method of noise reduction.