二维离散余弦变换的图像压缩 直方图均匀化 数字图像矩阵数据的显示及其傅立叶变换 模拟图像受高斯白噪声和椒盐噪声的影响 -Two-dimensional discrete cosine transform image compression histogram equalization of digital image data matrix display and the analog image by the Fourier transform of Gaussian