A 32 Mbit/s Component Separation DPCM Coding System for NTSC Color TV

A component separation DPCM Coding system is described which is capable of transmitting a 4 MHz NTSC color TV signal with broadcast quality at a 32.064 Mbit/s rate. The input NTSC color TV signal is first separated into a luminance component
Y
and two chrominance components
I
and
Q
. Then, these three components are converted into a TDM-PCM color signal, where
I
and
Q
of only odd lines are transmitted and samples in horizontal blanking intervals of
Y,I,
and
Q
are removed, in order to reduce the transmission rate. This TDM-PCM signal is encoded by a single DPCM coder, which employs a two-dimensional prediction method and a dual word-length coding method. For the
Y
signal, 4 bit and 8 bit code words are assigned to 29 quantizing levels. For both
I
and
Q
signals, 3 bit and 6 bit code words are assigned to 13 quantizing levels. Coding experiment results show that this coding system is promising for application to broadcast color TV signal transmission at a 32.064 Mbit/s rate.