A new approach to composite predictive coding for NTSC color TV signals has been proposed by Yamamoto et al. This technique involved integrating a comb filtering operation into an arbitrary linear predictor function tailored for monochrome signals. The prediction algorithms are valid as long as the sampling rate is half the integer multiple of the horizontal scanning frequency (15.7 KHz). Four intrafield predictors based on comb filtering integration (CFI) are applied to three test pictures sampled at 3f_sc where f_sc = 3.58 MHz is the color subcarrier frequency. With phase alternating line encoding (PALE) the data is aligned vertically. The predictors and the position of pels are shown in Table 1 and Figure 1, respectively. The variances of the prediction error were computed without the quantizer in the DPCM loop. Comparison of these variances shows that the CP1 is the best among the four predictors. Max quantizers with 5 bit, 4 bit and 3/6 bit (13 levels normal mode, 7 levels forced mode) based on the statistics of the prediction error of the CP1 are developed. Based on the occurrence frequency of the long word code (6 bit code) for the three test pictures, the buffer is designed, for constant bit rate transmission. For this processing, a single color TV channel can be transmitted at 32 MBPS which includes audio, error correcting code and synchronization bits.

Date Published: 17 March 1983
PDF: 5 pages
Proc. SPIE 0359, Applications of Digital Image Processing IV, (17 March 1983);

Published in SPIE Proceedings Vol. 0359:
Applications of Digital Image Processing IV
Andrew G. Tescher, Editor(s)