基于动态范围调整的图像亮度修正方法

摘要

The popularity of handheld camera allows people to capture images more easily, but the photos shot are often affected by the problem of refraction angle and lighting, thus their effect is impacted, so the technology of image restoration, especially of hue repairing are given great attention.Image dynamic range describes the ratio between the largest and the smallest brightness of the image, the method of hue mapping it to compress the high dynamic range to the range displayable with general displayer.On the basis of local window-based global optimisation method, we use Heaviside step equation to adjust the image with low dynamic range to reach the effect of image's brightness repairing.This method is simple in operation, at the same time has very good colour fidelity and can retain image details.In terms of the vision, the perceived colour is closer to the original image.%手持照像设备的普及让人们可以更方便地获取图像，但拍得的照片常常会由于拍摄角度及光照的问题而影响效果，因此图像修复特别是对色调的修复技术受到极大重视。图像动态范围描述图像中最大的和最小的亮度之间的比值，色调映射方法是将高动态范围压缩到普通显示器可显示的范围内。在基于局部窗口的全局优化方法的基础上，采用阶跃方程对低动态范围图像进行调整，达到修复图像亮度的效果。该方法运算简单，同时具有很好的色彩保真度，且调整后图像的细节保持良好。从视觉上来说，感知到的色彩更接近原始图像。