模糊图像点扩散函数的亚像素精度离散化方法

摘要

Fast and accurate Point Spread Function (PSF) estimation method is the premise to obtain good results on the blur image restoration. To solve the deficiency of the discrete PSF of defocus-blurred and motion-blurred images, a discretization method was proposed based on the combination of geometric property of degradation model and sub-pixel estimation. Specifically, the principle of weight allocation was defined, which was related to the distance with the neighboring pixels: Thus, the discretization of PSF was realized. Finally, the experimental results illustrate that the proposed method improves result precision and outperforms the traditional one on visual quality, sharpness evaluation function, Peak Signal-to Noise Ratio (PSNR) and Improved Signal-to-Noise Ratio (ISNR).%快速准确的点扩散函数(PSF)估计方法,是获取良好模糊图像复原效果的前提.针对散焦模糊和匀速运动模糊的PSF在以往离散化实现过程中的近似误差问题,提出一种结合退化模型几何性质和亚像素估计的离散化方法,定义了近邻像素点的距离相关权值分配原则,并以此进行亚像素精度的估计,从而实现了PSF的离散化.实验结果表明该方法的估计精度有很明显的提高,并在主观视觉质量和客观图像清晰度评价函数、峰值信噪比(PSNR)、改善信噪比(ISNR)方面均优于传统方法.