Giuseppe Valenzise
ABSTRACT
This paper considers the problem of transcoding multiple video sequences in order to enable transmission across a channel characterized by a limited bandwidth. At each time instant, the available bit budget needs to be optimally allocated to the sequences in order to minimize the output average distortion. Nevertheless, this criterion does not guarantee that the quality of the reconstructed sequences is the same. Therefore, we seek for a solution that minimizes the output distortion variance, and we show that we achieve constant quality while keeping the penalty in average distortion small. We formulate this problem in the ρ-domain, and we show that the model parameters needed to solve the optimization problem can be easily extracted from the incoming compressed bitstreams. In addition, if a global video buffer can be accommodated, we show that it is possible to smooth the overall video quality along time. Experimental results on H.264/AVC compressed video data validate the performance of the proposed algorithm.
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Digital Library
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Index Terms
- A smoothed, minimum distortion-variance rate control algorithm for multiplexed transcoded video sequences
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