产生亮块图像f1(x, y)（128×128，暗处灰度值为0，亮处灰度值为255），对其进行离散傅里叶变换，同屏显示原图像及其频谱图。-To produce bright block images f1 (x, y) (128128, dark gray level value of 0, and light at the gray scale value of 255), its discrete Fourier transform, with the screen display of th