A multichannel optical Fourier transform has been proved to be a useful method for encoding spatial-frequency or density pseudoeolor[1]. The method of image-processing is accomplished by spatial-filtering the various time frequency channels. Compared with the Ronehi grating methods[2], this method has the advantages of high utilization ratio of light source, has no image resolution loss caused by grating sampling and does not require Fourier transforming lenses of large relative aperture.