摘要 |
A wide-aspect-ratio HDTV signal having 1600 luminance pixels/32 mu S line and 980 lines/frame is data reduced by deleting odd pixels of each line of TV field #1 and even pixels of each line of TV field #2 to produce 800 pixels per line, and is further data compressed by a form of differential-pulse-code modulation. The DPCM organizes the pixels into groups of five, and for each group transmits or records one reference pixel at full N-bits. The pixels to the right and left of the reference pixel are compared therewith to produce difference signals of M bits, where M<N. The remaining two pixels of each group are compared with reference pixels from the lines above and below to form M-bit difference signals. The difference signals are transmitted. The DPCM coding reduces the 800 pixels/line to the equivalent of 480 pixels/line. The color portion of the wide-aspect-ratio HDTV is similarly coded to produce the equivalent of 240 pixel/line. The 480 luminance samples and 240 color samples are added to form 720 samples/line, or 1440 samples/64 mu sec which can be accommodated by a CCIR-standard-601 signal processing system.
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