Soft Real Value Video Broadcast Scheme Based On Unequal Protection

With the popularity of mobile Internet, wireless mobile video traffic is growing dramatically. Conventional digital video coding systems cannot adapt the wireless broadcasting scenarios since the separate source coding and channel coding, which inevitably suffers from cliff effect.Recently, the analog video broadcast systems, which is represented by SoftCast, directly transmits analog signal, preserving the numerical characteristics so that it can solve the cliff effect fundamentally.In this paper, we investigated soft video broadcast based on real value and propose a scalable wireless video broadcast scheme based on unequal protection. SoftCast performs data process over chunks, which leads that some important data can not be protected adequately, while the non-important data would waste part of the resources. In our scheme, the pseudo coset coding operation reduces the value of the important data and the covariance of the block. Meanwhile, allocate more resource for important data to realize unequal protection. The proposed scheme improves the utilization of the resource and enhances the quality of reconstruction video. Simulations show that the proposed scheme based on unequal protection can completely eliminate the cliff effect and its performance of construction quality is about 3?5dB better than 3D DCT SoftCast under the same conditions.Although the scheme based on unequal protection improves the performance of reconstruction quality, its adaptability is not well. And also, the whitening operation does not have enough flexibility which is caused by Hadamard matrix. So an adaptive scalable wireless video coding scheme is proposed. In this scheme, an adaptive data processing strategy is utilized, which process data according to the channel condition and video content. And it improves the reconstruction quality in high SNR. Furthermore, a more flexible whitening operation is proposed. The quadtree partition whitening can provide more flexibility without loss of performance. The simulation results show that the reconstruction quality of adaptive video scheme is 0.3?1 dB better than the proposed scheme based on unequal protection and provide better adaptability.Transmission scheme based on gradient image has large amount of transmission data and its operation only for picture. We study the characteristics of gradient data and propose a video transmission scheme based on gradient information unequal protection. By eliminating the inter-frame redundancy, single-frame processing module would be extended to the video sequence. Meanwhile,it reduces the amount of data transmitted, and improves the subjective visual quality of the reconstructed video by the operation of unequal protection of important data and filter noise reduction. The simulation shows that the unequal protection scheme based on gradient information reduces the amount of data transmitted and the reconstruction performance is improved by 1.5?2dB compared with SoftCast.