An image processing apparatus able to instantaneously transmit image data on which a color/monochrome judgment and a series of processings have been performed comprising: a color/monochrome judging device for judging if input RGB image data is color or monochrome; a color image correction processing unit for performing color image correction processing on the RGB image data and outputting color image data; a monochrome image conversion processing unit for performing monochrome image conversion processing on the RGB image data and converting the same to monochrome image data; image accumulation device for accumulating color image data and monochrome image data; a network I/F for transmitting the image data accumulated in the image accumulation device to an external network; and accumulation control device for outputting either the color image data or monochrome image data accumulated in the image accumulation device to an external network in accordance with the color/monochrome judgment result.