Abstract: In order to solve the problem of information loss caused by local motion blur in daily captured images or videos, a local motion detection algorithm based on region energy estimation was proposed. Firstly, the Harris feature points of the image were calculated, and alternative areas were screened out according to the distribution of feature points of each area. Secondly, according to the characteristic of smooth gradient distribution in monochromatic areas, the gradient distribution of the alternative areas was calculated and the average amplitude threshold was used to filter out most of areas which can be easily misjudged. At last, the blur direction of the alternative areas was estimated according to the energy degeneration feature of motion blur images, and the energy of the blur direction and its perpendicular direction were calculated, thus the monochrome region and defocus blur areas were further removed according to the energy ratio in both above directions. Experimental results on image data sets show that the proposed method can detect the motion blur areas from images with monochromatic areas and defocus blur areas, and effectively improve the robustness and adaptability of local motion blur detection.

Key words: motion blur, defocus blur, deblurring, point spread function, image gradient

摘要： 为了解决日常拍摄的图像或视频中普遍存在局部运动模糊导致信息丢失的问题，提出一种基于能量估计的局部运动模糊检测算法。该算法首先计算图像的Harris特征点，根据每个区域内的特征点分布筛选出备选区域；然后根据近单色区域梯度分布平滑的特点，通过计算备选区域的梯度分布并参照平均幅值阈值过滤掉大部分容易被误判的部分；最后根据运动模糊对图像能量衰减的特征对备选区域进行模糊方向估计，并计算模糊方向和与其垂直方向的能量，根据两个方向上能量的比值进一步去掉单色区域和散焦模糊区域。在图像库上的实验结果表明，所提算法能较好从存在近单色区域和散焦区域干扰的图像中检测出运动模糊区域，有效提高局部运动模糊检测的鲁棒性以及适应性。

关键词: 运动模糊, 散焦模糊, 去模糊, 点扩散函数, 图像梯度