Research And Implementation Of Paralleliaztion Of HEVC Video Decoding Module For National Standard Video System

The HEVC encoding standard is a video encoding standard developed by the ITU-TVCEG after the H.264 encoding standard.Compared with H.264,HEVC standard improves the video compression efficiency and error recovery capability and HEVC can transmit higher quality video under the limited transmission bandwidth.However,the improvement of the encoding complexity of HEVC leads to the low efficiency of video codec.In addition,media decoding consumes resources,especially soft decoding requires higher processors and memory resources,while the National Standard Video System requires soft decoding of media data,which puts forward certain requirements on the performance.In view of these problems,designing and implementing a parallel decoding method based on multi-core and multi-thread to improve the decoding efficiency of the system,which has important research significance and practical value to improve the decoding performance of the National Standard Video System.The main work of the thesis is as follows:(1)Aiming at the problem that the image reconstruction module of the HEVC decoder in FFmpeg cannot realize parallel operation,a method of decoupling the entropy decoding module in the HEVC decoder from the image reconstruction module is proposed.The extra storage space is used to store the results of each CTU entropy decoding,so as to realize the goal of parallelizing the image reconstruction module and speeding up video decoding.(2)In order to solve the problem of inefficient video decoding and low CPU utilization in the system,using the parallel idea of multi-core and multi-thread to propose to use the parallel working method based on CTU line to decode the image reconstruction module and the loop filter module in parallel.Modify the filtering order of removing block filtering in the loop filter module to shorten the waiting time between threads.By using pipeline parallel decoding technology,the entropy decoding module,image reconstruction module,and loop filtering module are combined to achieve the goal of improving the decoding efficiency of the National Standard Video System.The experimental results show that the designed and implemented parallel decoding module has better practicability and good performance in the National Standard Video System.