Optical screen television signal processing system to improve uniformity of central and side panel image resolution

摘要

An NTSC compatible widescreen EDTV system encodes and decodes a television signal (N) comprising (1) a main, standard format NTSC signal with auxiliary low frequency side panel image information compressed into an overscan region thereof; (2) auxiliary high frequency side panel image information (X); and (3) auxiliary high frequency horizontal luminance information (Z). At an encoder, components 2 and 3 are intraframe averaged (64, 76) before modulating an alternate subcarrier (80). Component 1 is intraframe averaged (38) exclusive of the compressed side panel information before being combined (40) with the modulated alternate subcarrier.