为改善图像质量，采用平均去背景的方法增强图像，利用图像直方图找到图像亮度出现频率最高的像素点，把该点作为背景消除。-To improve image quality, using the average debackground method to enhance the image, the use of the image brightness of the image histogram to find the highest frequency of the pixel, to the point as the background eliminated.