Slow-scan television (SSTV) is a picture transmission method used by amateur radio operators to transmit and receive static pictures via radio in either color or monochrome. When originally explored, SSTV required some extensive equipment but, since the early 1990s, a personal computer and special software has replaced much of the custom equipment. The PC's sound card with special processing software acts as a modem. The computer screen provides the output. A small digital camera or digital photos provide the input.
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