The frequency domain plays an important role in image processing to smooth, enhance, and detect edges of images. Although image data typically does not include imaginary values, the fast Fourier transform (FFT) has been used for obtaining spect

huffman编码用于图像的压缩和解压，很好用的，可以用于各类图像的处理-huffman coding for image compression and decompression, useful, and can be used for all kinds of image processing