NTSC and PAL compatible digital encoder

摘要

A digital encoder for use in both NTSC and PAL systems includes a demultiplexer for separating a time-division color difference signal R-Y/B-Y into color difference signals R-Y and B-Y. The separated color difference signals R-Y and B-Y are converted by a sub-carrier frequency converter into a sub-carrier frequency, and a digital modulator determines levels and phases of the converted color difference signals. A burst generating circuit generates a burst signal after determining a level and phase of the burst signal, and a chroma encoder produces a chroma signal by mixing an output of the digital modulator with the burst signal.