Dynamic Sub-GOP Forward Error Correction Code for Real-Time Video Applications

摘要

Reed-Solomon erasure codes are commonly studied as a method to protect the video streams when transmitted over unreliable networks. As a block-based error correcting code, on one hand, enlarging the block size can enhance the performance of the Reed-Solomon codes; on the other hand, large block size leads to long delay which is not tolerable for real-time video applications. In this paper a novel Dynamic Sub-GOP FEC (DSGF) approach is proposed to improve the performance of Reed-Solomon codes for video applications. With the proposed approach, the Sub-GOP, which contains more than one video frame, is dynamically tuned and used as the RS coding block, yet no delay is introduced. For a fixed number of extra introduced packets, for protection, the length of the Sub-GOP and the redundancy devoted to each Sub-GOP becomes a constrained optimization problem. To solve this problem, a fast greedy algorithm is proposed. Experimental results show that the proposed approach outperforms other real-time error resilient video coding technologies.