Research On Technology Of Large Capacity And Low Delay Joint Source Channel Coding Video Transmission

With the vigorous development of multimedia communication business,in recent years,a series of real-time multimedia transmission business requirements such as virtual reality experience,driverless car,image intelligent recognition,and monitoring emerge,which makes the real-time reliable transmission of Ultra-High Definition Video gradually become the general demand.This needs higher transmission rate,low delay,and high reliability to support.In order to overcome these challenges,there are still many problems to be solved in the existing high-speed wireless video transmission technology.For example,the processing complexity caused by huge amounts of Ultra-High Definition Video data increases,how to improve the transmission reliability in the complex channel environment and obtain the low delay characteristics of the whole video wireless transmission link while ensuring the video quality.However,the traditional separation design way of source and channel independent coding is difficult to meet the application requirements above.The joint source channel coding technology is an effective way to solve the above problems.This paper aims at the above difficult technical problems,and deeply studies the key technologies of joint source channel coding and transmission of low delay and Ultra-High Definition Video.The main research contents are summarized as follows.(1)Firstly,this paper introduces the existing theoretical basis of the Ultra-High Definition Video codec algorithm and the source channel joint coding technology.secondly,it makes an in-depth analysis of the technical difficulties faced by the low delay and high reliability UHD video transmission in the complex indoor channel environment,with the emphasis on the low delay Ultra-High Definition Video compression codec algorithm and JSCC video stream loading and modulation method for MIMO-OFDM system.(2)The low delay Ultra-High Definition Video compression coding and decoding algorithm is studied in this paper.In view of these problems of high computational complexity,high coding and decoding delay,and high loss of video quality in the existing compression coding and decoding algorithms,an Ultra-High Definition Video compression coding and decoding algorithm based on asymmetric wavelet transform is proposed.The algorithm uses asymmetric wavelet transform to reduce the spatial redundancy between video data and the buffer delay introduced by column transform,and it can be used to reduce the visual redundancy according to the characteristics of human vision,and then leverages the lightweight entropy coding algorithm to reduce the statistical redundancy.At the decoder,the video parameters are firstly analyzed,and then the coefficients are obtained by entropy decoding according to these parameters,and finally the video sequence is restored by inverse transformation.Theoretical and simulation results show that the proposed algorithm can significantly reduce the computational complexity of Ultra-High Definition Video compression,and decrease the processing loop delay while ensuring the quality of video image restoration.(3)JSCC video stream loading and modulation method for MIMO-OFDM system is studied.In order to meet the requirements of high-speed and reliable video transmission in indoor environment,JSCC video stream loading and modulation method for MIMO-OFDM system is proposed.Firstly,the importance of video stream data is divided;Then,two levels of unequal error protection are implemented in channel modulation and MIMO spatial channel mapping.Finally,the OFDM modulation algorithm with ideal channel feedback is considered.Simulation results show that the algorithm can achieve unequal error protection for source important data,and can improve the objective quality of video image by 5-15 db compared with the traditional fixed modulation algorithm.