产生右图所示亮块图像 f1(x,y)（128×128大小，暗处=0，亮处=255），对其进行FFT，同屏显示原图f1和FFT(f1)的幅度谱图，若令f2(x,y)=（-1）x+y f1(x,y)，重复以上过程。以及旋转45度后进行变换-Generating shown bright block image F1 (x, y) (128128 size dark = 0, light at = 255), the FFT, the same screen display Original f1 and FFT (f1) of the amplitude spectrum FIG Let f2 (x, y) = (-1) x+y f1 (x, y), the above process is repeated. And rotated by 45 degrees to transform