Patent ID: 8824567

Claim:
A method for tracking error propagation in a digital video encoder that encodes a digital video, the digital video having a plurality of image frames, and each image frame having a plurality of blocks of pixels, wherein a pixel dependency count for a block of pixels is initialized at a first image frame of the digital video, the method comprising the steps of: resetting the pixel dependency count for the block of pixels if the block of pixels is a part of an intra-coded macroblock in a current frame, wherein the pixel dependency count is indicative of a level of error propagation within the block of pixels; if the block of pixels is not part of the intra-coded macroblock in the current frame, computing, using a computing device, the pixel dependency count for the block of pixels in the current frame as a function of pixel dependency counts of one or more blocks of pixels in one or more preceding image frames used for motion compensating the block of pixels in the current frame; and updating the computed pixel dependency count of the block of pixels in the current frame using an updating function; and refreshing one or more macroblocks, wherein the macroblock includes one or more blocks of pixels, and wherein refreshing the one or more macroblocks comprises: obtaining for each macroblock, a macroblock level pixel dependency count as a function of the pixel dependency count of one or more blocks included in the macroblock; and selecting for refresh one or more macroblocks according to the macroblock level pixel dependency counts of the selected macroblocks to limit error propagation in the macroblocks in following image frames, wherein the one or more macroblocks are selected according to a histogram, the histogram being representative of a relation between a value of the macroblock level pixel dependency count and a number of macroblocks having that value.