Image data identification circuit and panel system controller

A video data identification circuit (12) for identifying video data output from a video data reception circuit (11) and controlling a drive current of a source driver, the video data identification circuit (12) being provided with: a memory (122) for storing video data of a current horizontal line and video data of a plurality of horizontal lines preceding the current horizontal line among the video data; an image pattern detection circuit (123) that reads the pattern of the image data of the plurality of horizontal lines stored in the memory (122) when the image data of the current horizontal line and the image data of the previous horizontal line are compared and do not match; and a drive current setting circuit (124) that sets a drive current for driving the source driver (13) of the current horizontal line on the basis of the pattern of the image data of the plurality of horizontal lines read from the memory (122) by the image pattern detection circuit (123).