Error concealment using wide motion vector space for H.264/AVC

Due to fast growth of wireless mobile networks, video transmission over wireless media has been widely studied. As wireless networks are error prone, there is a high possibility of loss in sent packets. Since time limitations in real-time video applications should be met, the delay-related to resending packets - is not acceptable and the error should to be concealed at receiver side. With respect to different concealment methods, two new methods for temporal error concealment are proposed. In the first method, an optimized set of motion vectors is formed using motion vectors in surrounding blocks of the lost macroblock, and then this set is searched for the best motion vector. For extending the candidate vector set, two best vectors - chosen by a distortion measure-are combined. The second method utilizes the first method but a pre-process is required for determining a better set of motion vectors to be searched. The preprocess consists of searching the motion vectors of neighbouring blocks to determine the range of search space. Distortion measure for choosing the best motion vectors is the MSE. When the macroblocks are more independent this method results in much higher PSNR compared to previous methods.