Mojtaba Marvasti-Zadeh - Department of Electrical and Computer Engineering, Yazd University, Yazd, Iran
Hossein Ghanei-Yakhdan - Department of Electrical and Computer Engineering, Yazd University, Yazd, Iran
Shohreh Kasaei - Department of Computer Engineering, Sharif University of Technology, Tehran, Iran

Error concealment is a useful method forimproving the damaged video quality in the decoder side. In thispaper, a dynamic method with low computational complexity ispresented to improve the visual quality of videos when up to 50%of the frames are damaged. In the proposed method, temporalreplacement and the improved outer boundary matchingalgorithm are used for dynamical error concealment in interframesof videos. With the use of motion vectors (MVs) which areclose to the damaged macroblock (MB) the method can determinewhether the motion in specific areas is either regular, irregular,or zero. Then, based on this knowledge, different methods areperformed. It adaptively selects a set of candidate MVs andexternal boundaries for comparison purposes. Furthermore, toincrease the accuracy, depending on the correctness of adjacentMVs, a specific weight is given to the boundaries of adjacentMBs. Experimental results show that the proposed methodenhances both objective and subjective quality of damagedframes without any considerable increase in complexity. Theaverage PSNR in some frames of test sequences has increasedabout 1.01 dB more than the outer boundary matchingalgorithm.

temporal error concealment; motion vector estimation; outer boundary matching algorithm; temporal replacement