1. An electronic camera apparatus comprising: an image capturing unit to capture an image of an object and outputs image data; an ROI recognition unit to recognize a region of interest (ROD of the image data using a plurality of different ROI recognition methods; an ROI control unit to select one ROI recognition method from the different ROI recognition methods according to a function related to image capture of the object or a user designation and set ROI information based on a recognition result obtained by the selected ROI recognition method; and a compression unit to perform a compression process on the image data according to the ROI information set by the ROI control unit; wherein the selected ROI recognition method recognizes the ROI by detecting a region of the image data in which patterns having a striking contrast are concentrated and using the region as a base region.