A timing controller for a display processing device includes: a plurality of predetermined pins for receiving an image signal by a pin-share method, wherein the image signal is a first format image signal or a second format image signal; a detector coupled to the predetermined pins and for detecting at least one of the predetermined pins to determine whether the image signal is the first format image signal or the second format image signal and outputting a detection result; and a processor coupled to the detector and for processing the image signal according to the detection result to generate and output a timing control signal.