An electronic device determines to transmit an image including a matrix code to a display, receives input specifying to alter the matrix code, generates an updated image according to the input, and transmits the updated image to the display. The device may alter a size and/or position of the matrix code, a display duration and/or complexity of the matrix code, and so on. The device may generate the matrix code and modify it in response to input, receive different matrix code versions and select a different version in response to input, receive the image including the matrix code and generate a replacement to overlay over the image, and so on Additionally, independent of input, the device may receive an image, detect an included first matrix code, generate a second matrix code based on the first, and generate an updated image by adding the second matrix code to the image.