DETECTING ERRORS IN VIDEO IMAGES

摘要

An error is identified in a video image by calculating frequency-related coefficients for blocks of the image and considering the statistical distribution of said coefficients. The variance of coefficients is calculated and a block of original image data is concealed if the variance calculated is significantly higher than a stored threshold and/or if said variance calculated is significantly different from variance values derived for similarly positioned blocks within a previous frame. Concealment is effected by selecting image data from a previous frame, displaced in response to transmitted motion vectors.