Denoising filter

A method for filtering a sequence of pixels, each pixel having an associated pixel value, the method comprising:

• recursively filtering the sequence of pixels in a particular direction so as to form a filtered pixel value for each pixel by, for each pixel:
• reading a filtered pixel value for a preceding pixel of the sequence with respect to the particular direction,
• scaling the filtered pixel value of the preceding pixel of the sequence by a non-binary measure of similarity between data associated with the pixel and the preceding pixel, and
• forming a filtered pixel value for the pixel in dependence on the pixel value of the pixel and on the scaled filtered pixel value for the preceding pixel;
• and
• generating a filter output for the pixel in dependence on the respective filtered pixel value.

A non-transitory computer readable storage medium having stored thereon computer readable code that, when processed by a computer system for generating a manifestation of an integrated circuit, cause the computer system to generate a manifestation of a pixel filter comprising:

• an input arranged to receive a sequence of pixels, each pixel having an associated pixel value;
• a filter module arranged to perform a recursive filter operation in a particular direction through the sequence of pixels so as to form a filtered pixel value for each pixel in dependence on the pixel value at that pixel and the filtered pixel value for a preceding pixel in the sequence of pixels, the filtered pixel value for the preceding pixel being scaled by a non-binary measure of similarity between data associated with that pixel and its preceding pixel;
• and
• filter logic configured to generate a filter output for each pixel in dependence on the respective filtered pixel value.