Fourier transformations are used to calculate a power spectrum of an image of an integrated circuit. After a job is received, a determination is made as whether the received job is a \u201cshort-lived job\u201d or a \u201clong-lived job. Those cables are simultaneously winding themselves around a cable shaft rotated by a second drive motor so that cover remains tight between the cable shaft and the cover shaft. The transfer roller and the fixing roller being detachably installed on a frame of a transfer and fixing portion of said image forming apparatus.