PBPAIR: an energy-efficient error-resilient encoding using probability based power aware intra refresh

Error resilient encoding in video communication is becoming increasingly important due to data transmission over unreliable channels. In this paper, we propose a new power-aware error resilient coding scheme based on network error probability and user expectation in video communication using mobile handheld devices. By considering both image content and network conditions, we can achieve a fast recoverable and energy-efficient error resilient coding scheme. More importantly, our approach allows system designers to evaluate various operating points in terms of error resilient level and energy consumption over a wide range of system operating conditions. We have implemented our scheme on an H.263 video codec algorithm, compared it with the previous AIR, GOP and PGOP coding schemes, and measured energy consumption and video quality on the IPAQ and Zaurus PDAs. Our experimental results show that our approach reduces energy consumption by 34%, 24% and 17% compared with AIR, GOP and PGOP schemes respectively, while incurring only a small fluctuation in the compressed frame size. In addition, our experimental results prove that our approach allows faster error recovery than the previous AIR, GOP and PGOP approaches. We believe our error resilient coding scheme is therefore eminently applicable for video communication on energy-constrained wireless mobile handheld devices.