DIRECT-PREDICTIVE DIFFERENTIAL PCM OF NTSC COLOR TV SIGNALS.

This paper points out that the use of a planar prediction can improve the coding performance of the direct predictive coding systems for the NTSC color TV signal. Quantitative evaluation was made using the coding laboratory equipment designed for 32 Mbits/sec transmission. Analysis of the frequency response of the system shows that the planar prediction is well matched to the spectrum of the NTSC signal. The signal-to-noise ratio is approximately 42 DB with planar-predicted 4-bit-differential PCM (DPCM). In the case of ordinary broadcast programs, one can hardly tell the difference in picture quality between 4-bit DPCM and 8-bit PCM.