A fast simulation model for getting approximate degraded images was proposed to raise the low speed of the simulation of images degraded by inhomogeneous medium. The image was divided into several sub-blocks according to the field view. Point spread function matrix of the center in each sub-block was computed to construct the degraded matrix, which was corresponding to the pixel size. Each sub-blocks were approximately regarded as isoplanatic regions and the sub-block degrade images were obtained by convolution calculation. Seamless splicing of the entire field of view images were achieved by the way of a little overlap of the adjacent blocks. The distortion was also added to obtain the final degraded image. With an imaging simulation system built, multiple experiments were done to compare the similarity between the degraded images obtaining by proposed model and ray tracing method. Experiment results show that with the requirement of a certain similarity, the time of simulating an image with the size of 512×512 is about several milliseconds.
CUI Guang-mang, ZHAO Ju-feng,FENG Hua-jun, XU Zhi-hai,LI Qi, CHEN Yue-ting. Construction of fast simulation model for degraded image by inhomogeneous medium. J4, 2014, 48(2): 303-311.
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