一种光照不均匀图像的恢复增强方法

RECOVERY AND ENHANCEMENT METHOD FOR IMAGES ACQUIRED UNDER NON-UNIFORM LIGHTING

在图像采集过程中,由于实际环境中成像条件的限制,造成图像的背景光照不均匀。针对这一问题,提出基于背景变化拟合的图像恢复和增强算法。该算法首先从图像中提取空间位置合适分布的背景样点,然后作多项式拟合得到背景光照的分布特性,并通过调节对比度因子,达到恢复和增强图像的目的。实验结果表明,该方法能有效恢复不均匀光照背景,为实际图像处理应用提供了有效的前期处理。

The limitation of imaging condition in actual environment causes sometimes the non-uniform background light on the images when capturing. To correct this,a method of image restoration and enhancement is proposed based on the background altering and fitting. In the proposed method, properly spaced background sample pixels are automatically picked up from the image, and then they are used in polynomial fitting for obtaining distribution characteristic of background light. By adjusting the contrast factors according to statistical parameters, image restoi＇ation and enhancement can be achieved. Experimental results show that the proposed method can recover the non-uniform lighting background robustly, and is.a useful preprocessing step in practical image processing applications.