Checksum-Filtered List Decoding Applied to H.264 and H.265 Video Error Correction

The latest video coding standards, H.264 and H.265, are highly vulnerable in error-prone networks. Reconstructed packets may exhibit significant degradation in terms of peak signal-to-noise ratio and visual quality. This paper presents a novel list-decoding approach exploiting the receiver side user datagram protocol (UDP) checksum. The proposed method identifies the possible locations of errors by analyzing the pattern of the calculated UDP checksum. This permits considerably reducing the number of candidate bitstreams in comparison to conventional list decoding approaches. When a packet composed of N bits contains a single-bit error, instead of considering N candidate bitstreams, as is the case in conventional list decoding approaches, the proposed approach considers N/32 candidate bitstreams, leading to a reduction of 97% of the number of candidates. For a two-bit error, the reduction increases to 99.6%. The method's performance is evaluated using H.264 and H.265 test model software. Our simulation results reveal that, on average, the error was corrected perfectly 80%-90% of the time (the original bitstream was recovered). In addition, the proposed approach provides, on average, a 2.79-dB gain over frame copy (FC) error concealment using the joint model and a 3.57-dB gain over our implementation of FC error concealment in the High Efficiency Video Coding test model.