A composite DPCM codec system for carrying one broadcast quality NTSC color TV channel with two audio channels at the T3 rate of 44.736 Mb/s is designed and implemented.
The system is based on the sampling rate of $3f_{sc}$, a simple intrafield average predictor, a 71-level uniform quantizer, a variable-length entropy coder, and the suppression of horizontal blanking interval.
The procedure to choose the system parameters and the hardware structures are presented. To accomodate the speed requirement for real time processing, high speed ECL gates and H-MOS memory devices are used in the hardware implementation.
Experimental results show that the codec system is sufficiently good for real application. The expected SQNR is 53 dB.
