该代码是对人脸进行光照处理，先进行gamma变换，然后进行Dog双边滤波，然后进行灰度亮度的均衡。该方法能够有效提高光照变化的情况下的系统识别性能-The code is the human face of light treatment, the first for gamma conversion, and then Dog bilateral filtering, then the brightness of the gray balance. The method can effecti