Analysis of channel error upon selectively encrypted H.264 video

Abstract

Abstract-For real-time video streaming applications it is important to preserve both privacy and delay sensitivity. To achieve, this selective encryption exploits the entropy coding stage of hybrid codecs. As streaming applications move towards mobile networks, they become vulnerable to bit errors in the wireless channel. This paper is a pioneering analysis of the relative impact of bit errors on the two H.264 codec entropy coders, CAVLC and CABAC. The joint impact of compression and encryption on objective video quality is determined in experiments, when it is found that CAVLC is much more vulnerable to bit errors compared to CABAC. This finding will guide future bit error protection schemes.

VQProtect: Lightweight Visual Quality Protection for Error-Prone Selectively Encrypted Video Streaming

“…The selective encryption on MVDs and TCs keeps the video format compliant (playable) and without escalating bit rates. As previously discussed in the research of [24], H.264/AVC's CAVLC is more susceptible to channel errors as compared to CABAC. Thus, this paper devised a protection scheme for the H.264-CABAC entropy coder, which can be applied to HEVC compression, with a few comparatively minor modifications.…”

“…In [24], the authors examined the comparative effects of channel errors on selectively encrypted video bitstreams by two H.264 codec entropy coders Context Adaptive Binary Arithmetic Coding (CABAC) and Context Adaptive Variable Length Coding (CAVLC). They determined the combined effect of compression and encryption on the video quality and concluded that CAVLC is more susceptible to channel error.…”

“…They determined the combined effect of compression and encryption on the video quality and concluded that CAVLC is more susceptible to channel error. CABAC is being utilized by all advanced encoders; then, this finding [24] serves as a base to devise an advanced bit-error protection method for CABAC entropy coder of H.264/AVC (as considered in this paper). In [25], an extended Selective Encryption (SE) model for both H.264/AVC and HEVC encoded streams was introduced in which the regular mode of CABAC was used.…”

Sufficient encryption based on entropy coding syntax elements of H.264/SVC

“…The impact of noise on the proposed scheme was already examined by us in [5]. In that paper, it was concluded that CAVLC coding is significantly more sensitive to channel bit errors than CABAC.…”

Transparent encryption with scalable video communication: Lower-latency, CABAC-based schemes

“…In both these methods, the decoder bitstream remains format compliant. Other work by us has confirmed the resistance to perceptual attacks [25] and examined to what extent the core SE technique can tolerate errors in a wireless channel [26].…”