Image processing method and display device

An image processing method applied to a display device having a processing circuit and a screen, comprising:

• by the processing circuit, receiving a first image from one of a plurality of electronic devices;
• by the processing circuit, detecting whether the first image has a black border area;
• and
• if the first image has the black border area, by the processing circuit, performing a first display operation, wherein performing the first display operation comprises:
• removing the black border area of the first image, to generate a second image;
• adjusting the size of the second image according to the size of a display area of the screen;
• calculating a first blank area of the screen based on the adjusted second image;
• requesting a third image from another one of the electronic devices according to the size of the first blank area;
• and
• filling the display area of the screen with the adjusted second image and the third image.