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In this paper, we propose a fast rate control algorithm in frame-layer of H.264/AVC video coding standard. We derive a statistical relation between quantization parameter (QP) and encoded bits of inter-coded blocks. In addition, new complexity estimation is defined to determine weight of complexity of current frame. Using the statistical property and the complexity updating function, we determine the amount of bits as a function of quantization parameter, so that computational cost of rate control is significantly reduced with coding gain improvement and stable buffer management. Experimental results demonstrate the capability of the proposed algorithm. [ABSTRACT FROM PUBLISHER]

Dynamic Voltage and Frequency Scaling (DVFS) is an effective low-power technique for real-time workloads. Its effectiveness critically depends on the accurate prediction of the task execution time. Many DVFS approaches have been proposed, but they are insufficient for highly nonstationary workloads. Several recent DVFS techniques adopted adaptive filters to improve accuracy. However, their improvement was rather limited, since they mainly focused on applying a filter framework to the target application without tuning it. We address this issue by proposing Particle Filter (PF)-based video decoders (MPEG2 and H.264) which exploit application-specific characteristics. More specifically, our PF-based video decoders utilize the size of each frame for the prediction of its decoding time. Compared to previous work, the PF is more suitable for our purpose, since it achieves higher prediction accuracy, even for highly nonstationary workloads such as H.264 clips. Our results show that the energy saved by the proposed approach is comparable to that of the ideal policy called oracle-DVFS, while the existing methods we tested were far inferior to oracle-DVFS in terms of H.264 video decoding. Additionally, when our method was used, only 0.40 and 6.88 percent of the frames missed their deadlines with negligible computational overhead for MPEG and H.264, respectively. [ABSTRACT FROM AUTHOR]