The NTSC Color Hack
Stephen Cass (via Josh Centers):
This hack allows digital systems without specialized graphics hardware to produce color images by exploiting quirks in how TVs decode analog video signals.
NTSC artifact color was used most notably by the Apple II in 1977, where Steve “Woz” Wozniak’s use of the hack brought it to wide attention; it was later used in the IBM PC and TRS-80 Color Computers. But it was unclear where the idea had originally come from, so we were thrilled to see that video game and electrical engineering legend Allan Alcorn left a comment on the article with an answer: the first color computer graphics that many people ever saw owe their origin to a cheap test tool used in a Californian TV repair shop in the 1960s. IEEE Spectrum talked to Alcorn to find out more[…]
