27 February 1996 Overflow-free video coders: properties and optimal control design
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Proceedings Volume 2727, Visual Communications and Image Processing '96; (1996) https://doi.org/10.1117/12.233204
Event: Visual Communications and Image Processing '96, 1996, Orlando, FL, United States
The control of video coders to adapt their variable output bit-rate to the input requirements of communication channels constitutes a well known problem which attracts considerable attention from researchers in the field. The importance of the problem stems from the freedom that international standards (such as MPEG) allow in the design of the rate control algorithm, which makes it one of the main reasons for difference in quality between same-standard coders from different manufacturers. In real-time applications the main concern in controlling the coder is to ensure a buffer overflow-free operation with a limited look-ahead in the analysis of the sequence while optimizing the quality of the encoded signal. Stochastic optimal control constitutes a systematic approach to obtain the control policy which minimizes in the long- term an average cost function. Provided that a modelization of the coder as a stochastic system is possible, the application of this theory becomes a way to avoid heuristic design. Within this frame, in this paper we concentrate on the obtainment of those policies which ensure that no buffer overflow occurs (overflow-safe policies). The condition for their existence is provided along with their main properties and the definition of a stochastic optimal control problem which can be solved using standard algorithms in order to obtain optimal overflow-safe policies. Results of the application of the approach to the control of a standard coder are provided.
© (1996) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Jose Ignacio Ronda, Jose Ignacio Ronda, Fernando Jaureguizar, Fernando Jaureguizar, Narciso N. Garcia, Narciso N. Garcia, } "Overflow-free video coders: properties and optimal control design", Proc. SPIE 2727, Visual Communications and Image Processing '96, (27 February 1996); doi: 10.1117/12.233204; https://doi.org/10.1117/12.233204

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