Method and system for processing a page-image based input document such as PDF and generate output documents, in a page-image based format or another format, which have a different layout than the original document. Certain contents in the original document removed and other contents are reorganized in this process. The method is used to re-target documents for different types of display devices, such as desktop and laptop computers, tablet computers, e-readers, smart phones, etc. When generating the output documents, the method takes into consideration the different form factors of the display devices as well as the different types of user input devices and methods such as touch screen (including different gestures used, whether stylus or finger is used for input, etc.), physical keyboard, mouse, etc. used by the targeted display device, so that each output documents is optimized for a particular type of display device.