Video Quality Optimized Scheme Based On SoftCast

In recent years, analog schemes represented by SoftCast and the related hybrid digital-analog video multicast schemes have received extensive attention. These schemes overcome the "cliff effect" of traditional digital schemes and have good objective quality of video. In order to further improve the subjective quality of video, this paper mainly studies the optimization scheme of video transmission quality based on SoftCast, and puts forward the following several optimization schemes.In order to improve the subjective quality of SoftCast, this paper proposes an optimized scheme of SoftCast video transmission based on SSIM. Through the research of video quality evaluation standard, this scheme optimizes the power allocation algorithm of SoftCast according to the principle of structural similarity (SSIM) of subjective evaluation standard. Simulation results show that the proposed scheme has a certain quality gain compared with the original SoftCast scheme.In order to improve the subjective quality of HDA (Hybrid Digital and Analog), this paper proposes an optimization scheme based on visual information. According to the characteristics of human visual system(HVS), this scheme decomposes the video into visual information and insensitive information, and uses discrete wavelet transform to decompose insensitive information. At the same time as the focus of the protection of visual information and save power consumption, the program uses a combination of digital-analog transmission and optimization of the power distribution algorithm. Simulation results show that the scheme has some objective and subjective quality gains compared with SoftCast, WSVC and H.264 / AVC.Aiming at the characteristics of the human vision that is sensitive to the foreground information, this paper proposes a SoftCast video transmission optimization scheme based on image segmentation.According to the image segmentation algorithm, the video source is decomposed into foreground information and background information,and is encoded and transmitted in the way of SoftCast. In addition, an optimized power allocation algorithm is designed to protect the foreground information. Simulation results show that the scheme has some objective and subjective quality gains compared with SoftCast,WSVC and H.264/AVC.