考虑CCD噪声条件下的编码曝光最优码字搜索方法  

Searching for the optimal code of coded exposure photography in the presence of CCD noise

作　　者：黄魁华[1] 张军[1] 徐树奎[1] 李国辉[1] 

机构地区：[1]国防科技大学信息系统与管理学院,湖南长沙410073

出　　处：《国防科技大学学报》2012年第6期72-78,共7页Journal of National University of Defense Technology

基　　金：国家自然科学基金资助项目(60902093;61170159);国防科技大学优秀研究生创新基金资助项目(S080501)

摘　　要：编码曝光技术将病态的运动模糊图像复原问题转化为良态问题,寻找最优码字是编码曝光技术的关键。面向实用化目的,提出了一种考虑CCD传感器噪声的编码曝光相机最优码字搜索方法。基于仿射噪声模型对图像成像过程中的噪声成分进行了系统分析,首次从理论上分析了Raskar码字选取依据并基于复原图像信噪比增益提出了光子噪声对最优码字构造影响的解析表达式。在对实际编码曝光相机进行噪声标定的基础上,提出了最优码字搜索的准则并构造出适应度函数,采用遗传算法进行优化搜索得到最优码字。仿真图像和真实图像的复原结果证实了该方法的有效性,复原图像信噪比得到有效的提高。Coded exposure photography makes the ill-pose motion deblurring problem well-posed, and searching for the optimal code has been the key problem in coded exposure photography. For practical purpose, an optimal code searching method for coded exposure photography in the presence of CCD sensor noise is proposed. Firstly, the sensor noise in the process of imaging was systemically analyzed based on the affine noise model. Then, the basis of Raskar＇ s code was theoretically analyzed for the first time and based on the signal to noise ratio （SNR） gain of deblurred image, an analytic formulas between the photon noise and the structure of the optimal code was presented. Finally, based on the noise calibration of real coded exposure camera, the criteria for the optimal code was presented, a fitness function was designed and the optimal code using the genetic algorithm was obtained. Experimental results with synthetic and real data demonstrates the validity of the proposed method.

关 键 词：编码曝光 运动模糊复原 光子噪声 最优码字 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]