Methods and apparatus are described for measuring noise in video image processing. The described methods use horizontal and vertical variances of pixels of an image to extract noise information from the image. Silent regions in an image are considered to determine amplitude variations in the image. A smallest silent region in the image is searched by performing measurements over various block sizes. A least sum of absolute differences approach is used on both horizontal and vertical directions for finding the minimum energy of a received image signal. Using the disclosed method and processor, with a Gaussian distribution for the measured channel noise, both silent image regions, as well as edges, are equally covered.