Summary form only given. In this paper, Wyner-Ziv (WZ) video coding is a particular case of distributed video coding (DVC). Although some works, with improved performance, have been made in recent years, the coding efficiency of state-of-the-art WZ codec is still far from that of the state-of-the-art prediction-based codec, especially for high and complex motion contents. Moreover, most reported WZ codecs have a high time delay in decoder, which hinders its practical application in real-time systems. The performance of the SI creation process based on adjacent previously decoded frames is limited by the quality of the past and the future reference frames as well as the distance and motion behavior between them. In this work, by combining coding tools developed in recent literatures on transform domain WZ coding with some newly developed modules on both encoding and decoding sides, an efficient and practical WZ video coding architecture, dubbed as Distributed video coding with PArallelized design for Concurrent computing (DISPAC), is proposed to better the rate-distortion (RD) performance. Another unique feature of DISPAC, lies in the parallelizability of the modules used by its WZ decoder which increased the decoding speed largely. Experimental results conducted on a concurrent computing environment (consisting of multi-core CPU and GPU processors) reveal that DISPAC codec can gain up to 2.8 dB in the RD measures and 14.35 times faster in the decoding speed as compared with the-state-of-art WZ video codec, respectively. By shifting the computational complexity from the encoder to the decoder and integrating with appropriate trascoding techniques, DVC has been expected to provide a video codec solution for Cloud computing mobile devices (such as mobile phones).

In this work, by combining coding tools developed in recent literatures on transform domain WZ video coding with some newly developed modules on both encoding and decoding sides, an efficient and practical WZ video coding architecture, dubbed as DIStributed video coding with PArallelized design for Cloud computing (DISPAC), is proposed to better the corresponding rate-distortion (RD) performance. Another unique feature of DISPAC, lies in the parallelizability of the modules used by its WZ decoder which increased the decoding speed largely. Experimental results conducted on an emulated Could computing environment reveal that DISPAC codec can gain up to 3.6 dB in the RD measures and 60.97 times faster in the decoding speed as compared with the-state-of-art WZ video codec, respectively

Block mode selection is one new way to improve the performance of distributed video coding (DVC). Since there are many factors influencing the correctness of the block mode selection, the decision of block mode is not an easy work. In this paper, a low complexity block mode selection model is proposed to select the block modes more correctly in the WZ (Wyner-Ziv) frame. The proposed block mode selection modules can increase the RD performance up to 2.8 dB as compared with the traditional DVC codecs; moreover, the subjective quality can also be improved by using the proposed deblocking filter when the objective quality is kept the same.

Distributed video coding (DVC) is a new coding paradigm targeting applications with the need for low-complexity encoding at the cost of a higher decoding complexity. In the DVC architecture based on a feedback channel, the high decoding complexity is mainly due to the request-decode operation with repetitively fixed step size (induced by Slepian-Wolf decoding). In this paper, a parallel message-passing decoding algorithm for low density parity check (LDPC) syndrome is applied through Compute Unified Device Architecture (CUDA) based on General-Purpose Graphics Processing Unit (GPGPU). Furthermore, we propose an approach to reduce the number of requests dubbed as Ladder Request Step Size (LRSS) which leads to more speedup gain. Experimental results show that, through our work, significant speedup in decoding time is achieved with negligible loss in rate-distortion (RD) performance.