Error Control Technique For Three-Dimensional Video Transmission

Three Dimensional (3D) video that can deliver real and immersive experiences will be appliedin free-viewpoint video,3DTV, immersive teleconference, surveillance systems, et al. However,transmission of3D coded video over error-prone channels can lead to the loss of a few slices orframes. How to develop a robust error control technique is one of the most concerns of designingthe3D video systems.For these reasons, this thesis mainly focused on exploiting the spatial-temporal correlation andinter-view correlation of the double/multi-view sequences, and considering the content of picturesto design efficient error concealment (EC) techniques for3D video transmission. In summary, themain works of this thesis are listed as follows:(1) A block-activity based EC algorithm for stereoscopic video is proposed. We design fourparameters which are named temporal motion activity (TCA), motion compensated temporalactivity, inter-view disparity activity (IDA) and disparity compensated inter-view activity todescribe the motion and texture complexity of the adjacent frames at the same view, and thedisparity and texture complexity of the inter-view frames at the same time, respectively.According to the TCA, our method can choose appropriate motion compensated operation toconceal the lost motion compensated prediction (MCP) block. Also, According to the TCA,our method can choose appropriate disparity compensated operation to conceal the lostdisparity compensated prediction (DCP) block. So the proposed algorithm can convenientlychooses conceal approach according to the content of picture and makes the better tradeoffbetween the quality of concealed picture and the complexity of algorithm.(2) A region-based EC method for stereoscopic video is proposed. Based on the statistical analysisof the encoding modes of the surrounding macroblocks (MBs) and of the spatiallycorresponding MB in the neighboring frame, our method classifies the lost MBs into threecategories:(1) smooth MBs,(2) regular motion MBs and (3) irregular motion MBs. Followingthe classification, corresponding operations, including direct replacement, quarter-pixel motionand disparity compensation, and bilateral error concealment with adjustable weights, areapplied to reconstruct the smooth MBs, regular motion MBs and irregular motion MBs,respectively. The experimental result show that the similarity of concealed picture and originalpicture is high, especially, our method also make better subjective quality for irregular motionor texture region of the picture and solve the problem of the previous error concealment methods can not restore the lost irregular motion or texture region efficiently.(3) Based on the analysis of the correlation, a scalable EC algorithm for the whole B-frame loss indouble-view coded video is proposed. Our scheme focuses on stereoscopic video stream withHBP predicted structure and differs in several aspects from the prior work. First, according tothe model of frame important level, our scheme divides the lost frames into three types:1) thebest key frame;2) key frame;3) ordinary frame, and use different methods to different lostframe. It avoids the drawback of using the same method to conceal the different B frameswhich have different importance in the decoding process. Second, the proposed algorithmanalyses the correlation of motion vector (MV) and disparity vector (DV) in the double-viewvideo sequence, and selectively chooses the MV of corresponding block which is compensatedby disparity as the MV of the lost block. It improves the accurate of the estimated MV of thelost block. Third, the proposed algorithm divides the picture into different regions by utilizingthe object motion characteristic of the picture and the correlation which is acquired by thecorrelation analysis, and uses different approach to conceal different lost region. It improvesthe whole quality of the restore picture. Moreover, we introduce a frame-difference based ECalgorithm for key B-frame loss.(4) A scalable EC framework for multiview video coding is proposed. With this framework, wecan compute the importance level of frames of the different view in multiview video codingand use different approaches to conceal error pictures of different important levels. We proposea region based I-frame EC approach for multiview video coding with HBP prediction structrue.By utilizing the difference of frames at the same view, the proposed method first divides thelost MBs into smooth MBs and motion MBs, the former belonged to region of small framedifference and the latter belonged to region of large frame difference. Then, the lost smoothblocks are restored by direct copy and the lost motion blocks are recovered by the orientationinterpolation. Experimental result shows that the proposed method preserves the edge areas ofthe lost blocks efficiently, and offers significant average peak signal noise gain (up to1.76dBand1.77dB for the0-view sequence and2-view sequence respectively at the MB loss rate of20%) compared to the bilinear interpolation (BI) method which is employed in the H.264joint model (JM).(5) A robust stereoscopic video coding scheme is proposed to improve the performance of errorresilience.