The invention provides an image processing system which can give different securities to data of respective receivers with a simple operation and, in this case, which can realize shortening of time for communication to a destination and suppression of use of memory resources. A plurality of regions preset in image data are related to destinations, code data constituting one of regions corresponding to the destinations or the other regions is replaced with code data which make pieces of information included in the regions invisible in the JPEG2000 file transmitted to the destinations, and the JPEG2000 file after the replacing process is transmitted to the destinations.