Method of using region distribution analysis to automatically detect 3D image format

The invention relates to a method of using region distribution analysis to automatically detect a 3D image format. Software of a video processor of a 3D display is used for capturing images in two opposite identical regions in a video one frame image or two frames of adjacent images when video input is received so as to generate two region images, differences of brightness distribution or color distribution of the two region images are analyzed, whether the video is in a 2D video format or a 3D video format or other 3D video formats can be judged, the 3D display can thus be automatically switched to a proper display mode conveniently, no extra hardware is needed for processing a 3D video without 3D image format recognition information, and the cost can be reduced.