采用灰度变换的方法增强图像的对比度 直方图均匀化 模拟图像受高斯白噪声和椒盐噪声的影响 采用二维中值滤波函数medfilt2对受椒盐噪声干扰的图像滤波 -Gray-scale transformation of the methods used to enhance the contrast of the image histogram homogenization analog image by Gaussian white noise and salt and pepper noise