对于一幅输入图像，将产生一幅输出图像，输出图像的每个像素点的灰度值由输入像素点决定，将感兴趣特征的对比度扩展使之占据可显示灰度级的更大部分。使一输入图像转换为在每一灰度级上都有相同的像素点数，均衡化会减少灰度级数。大多数自然图像由于其灰度值分布集中在较窄的范围之内，引起图像细节不够清楚。采用直方图修正后可使图像的灰度间距拉大或使灰度均匀分布，从而增大了反差，使图像细节清楚，达到增强的目的。-For an input image, will produce an output image, the output image gray value of each pixel from the input pixel decided to expand interest in the contrast of features to make it account for more gray levels can be displayed most. Make an input image is converted to grayscale in each pixel have the same points, equalization will reduce the gray series. Most natural images because of their gray value distribution concentrated in a narrow range, causing the image detail is not clear enough. Make the image histogram revised by the gray space widening or so gray uniform distribution, thereby increasing the contrast between the image details clear objective to achieve enhanced.