Patent ID: 8908761
Filing Date: 2014-12-09
Classification: H04N

Abstract:
1. A method comprising: encoding a video image at each of a plurality of frames, including by using inter frame encoding to encode at least portions of some of the frames, thereby generating an encoded video stream; transmitting the encoded video stream over a lossy channel to be decoded at a receiver to produce decoded video; performing a recovery operation to refresh the encoding of the video image, cutting off error propagation that has occurred in the decoded video due to an effect of inter prediction in presence of loss over said channel; and maintaining an error propagation distortion map mapping one or more estimates of distortion due to said error propagation over different respective portions of the video image, wherein said recovery operation is triggered by a report fed back from the receiver indicative of loss; wherein the recovery operation is performed over a plural number of frames, refreshing the encoding of different partial frame regions at different respective frames, and wherein each of the partial frame regions encompasses one or more of said portions, and the partial frame regions are refreshed according to an order of priority over said number of frames, the order of priority being determined in dependence, at least in part, on the one or more estimates of distortion in the error propagation distortion map for the different portions, such that partial frame regions corresponding to greater estimated error propagation are refreshed in earlier of said number of frames and partial frame regions corresponding to lesser estimated error propagation are refreshed in later of said number of frames.