Image data transmission method and device, display controller and display screen control system

The embodiment of the invention discloses an image data transmission method, an image data transmission device, a display controller, a display screen control system and an LED display system. The image data transmission method is suitable for a display controller of a display screen control system, and the display screen control system further comprises a plurality of cascaded module controllers electrically connected with the display controller. The method comprises the following steps: determining one of the plurality of module controllers as a target module controller, and sending a target image line data packet to the plurality of module controllers according to load region coordinate information, load region height and load region width of the target module controller, the target image line data packet comprises recognition information and line packet data of the target module controller, and the data size of the line packet data is equal to the width of the loading region. The embodiment of the inventi