A parallel approach to the picture restoration algorithm of Geman and Geman on an SIMD machine

摘要

This paper considers how the image restoration technique of Geman and Geman, which involves searching for the maximum a posteriori distribution of an image modelled as bounded Markov random fields using simulated annealing, can be approximated on a parallel SIMD processor array, the ICL Distributed Array Processor (DAP). For the version implemented, the potential speed-up over an equivalent serial processor is equal to half the number of processors in the array, or 2048 for the 64×64 DAP. The time taken by the DAP for one updating cycle is about 30 ms, and the typical complete picture restoration consisting of 1000 annealing cycles takes around 30 s. A method of increasing the efficiency of the present algorithm is suggested and the possibility of making the algorithm work with several frames of data collected over time is discussed.