A compact CCD color camera system with digital AWB control

A novel signal-processing LSI was successfully developed for a compact CCD (charge coupled device) camera, where incident YRGB signals were converted into desired Y, C-Y signals, filtered, compressed, and automatically white-balanced. In order to realize accurate inner AWB (automatic white-balance) control, some ideas concerning white detection, white reproduction, and control speed were studied and developed with digital circuits. Specifically, digital circuits made a hold function, more accurate white detection, and a variable speed control possible