Complexity Of Multiview Video Coding Research Articles

Low-complexity encoding scheme for multiview video content

On-site multiview video viewing system can provide people with more immersive viewing experience on various live video shows, such as sports and concerts. To address the high computational complexity of multi-view video coding, several researches have worked on fast motion estimation, fast disparity estimation, and/or fast mode decision. In this paper, we propose a low-complexity encoding scheme that can further exploit inter-view dependencies and depth information. A fast mode selection with threshold-based early termination is presented to select a minimal set of mode candidates according to the reference macroblocks of neighbouring views and expedite the mode decision process. Further, this study also demonstrates that disparity estimation computation and search ranges of both motion estimation and disparity estimation can be significantly refined by using inter-view dependencies and depth information. The experimental results show that the proposed encoding method reduces the coding time by 80% with a negligible PSNR loss.

Early disparity estimation skipping for multi-view video coding

Multi-view video (MVV) and multi-view plus depth video became typical formats for 3D video systems which offer more realistic visual effects for consumers. The standard for encoding of MVV, known as multi-view video coding (MVC), was produced by ISO/IEC and ITU-T and has exhibited significant compression efficiency for MVV signals. However, the high computational complexity of MVC leads to excessive power consumption and limits its applications. In this study, new fast algorithms for MVC are proposed by skipping disparity estimation prediction. According to the characteristics of the motion and disparity vectors, unnecessary disparity estimation is skipped based on the amount of motion that can be measured through the use of motion activity and SKIP mode on the temporal axis. Experimental results showed that by skipping the disparity estimation, the proposed method reduced the encoding computational complexity by nearly 73% for inter-view prediction and 38% in the overall encoding process of B-views. In addition, no noticeable visual quality degradation was observed.

Coding statistics based fast mode decision for multi-view video coding

Reduction of high computational complexity of multi-view video coding (MVC) is necessary for realization in consumer electronics. Since mode decision is one of the key computational bottlenecks of multi-view video encoders, this paper proposes a coding statistics based fast mode decision algorithm. First of all, a rate–distortion cost based fast DIRECT mode decision algorithm early terminates the mode decision process if possible. Next, the candidates for Inter modes are reduced by taking the advantage of the correlation between an optimal mode and motion cost. The proper thresholds to reduce the candidates for the above two fast algorithms can be easily derived from exponential functions at run time. Finally, motion vector difference based motion characteristics is referred to further speed up the mode decision process of Inter modes. The experimental results show that the proposed scheme reduces up to 70.82% of encoding time with negligible degradation of RD performance.