Video coding with optimal inter/intra-mode switching for packet loss resilience

Abstract

Abstract-Resilience to packet loss is a critical requirement in predictive video coding for transmission over packet-switched networks, since the prediction loop propagates errors and causes substantial degradation in video quality. This work proposes an algorithm to optimally estimate the overall distortion of decoder frame reconstruction due to quantization, error propagation, and error concealment. The method recursively computes the total decoder distortion at pixel level precision to accurately account for spatial and temporal error propagation. The accuracy of the estimate is demonstrated via simulation results. The estimate is integrated into a rate-distortion (RD)-based framework for optimal switching between intra-coding and inter-coding modes per macroblock. The cost in computational complexity is modest. The framework is further extended to optimally exploit feedback/acknowledgment information from the receiver/network. Simulation results both with and without a feedback channel demonstrate that precise distortion estimation enables the coder to achieve substantial and consistent gains in PSNR over known state-of-the-art RD-and non-RDbased mode switching methods.

Scalable video coding with robust mode selection

“…The computational complexity of implementing ROPE algorithm at each layer is comparable to that of performing DCT [7]. It is important to note that the additional complexity is incurred only at the encoder.…”

“…Thus, the ROPE algorithm derived in [6,7] may be directly applied for calculating the total decoder distortion. We brie#y summarize the algorithm in this subsection.…”

“…While there is a considerable volume of published work on mode selection for packet loss resilience in the single-layer (non-scalable) video coding (e.g. [2,3,6,7]), very little work has been reported on the corresponding problem in scalable video coding.…”

“…The key step in our derivation is the estimation of the overall decoder distortion that takes into account the e!ects of quantization, packet loss and error concealment. To calculate this estimate, we extend the recursive optimal per-pixel estimate (ROPE) which we had proposed for non-scalable video coding [6,7]. The extended ROPE is shown to accurately account for both temporal and spatial error propagation, and to compute the total distortion in each layer at pixel-level precision.…”

Error-Exploiting Video Encoder to Extend Energy/QoS Tradeoffs for Mobile Embedded Systems

“…To cope with transmission errors such as packet losses, error-resilient video encoding techniques [2,9,15,16,18] have been investigated to reduce the effects of transmission errors on QoS. Most existing error resilient techniques judiciously adapt their resilience levels considering the network status.…”