An image processing apparatus such as a facsimile system has a CCD sensor for reading an original image, a detection circuit for detecting if a one-line image signal is a nearly black or white signal, a buffer memory for temporarily storing the image signal from the CCD sensor, and a microprocessor CPU for controlling the reading/recording operation in accordance with the detection result of the detection circuit. Image boundaries due to switching between reading and recording operations are eliminated from the reproduced image. A low-torque single motor may be used as a drive source in any of the transmission, reception and copying modes.