slow scan television (amateur radio) (SSTV)
In amateur radio there is a telecommunication service with which images can be transmitted. This service is called Slow Scan Television (SSTV).
Since amateur radio works with sound signal transmission, SS-Television assigns tones with different sound frequencies between 1 kHz and 3 kHz to the different brightnesses of the images. In SSTV transmission, the image to be transmitted is scanned, each pixel 's brightness is determined, and each brightness level is assigned a tone frequency. The audio frequencies are transmitted by radio in the order in which they are scanned and converted back to the corresponding brightness levels at the receiver end. In this way, the image sampled on the transmitter side is reconstructed and displayed on the monitor.
There are also SSTV methods with which color images can be transmitted.