Device for coding and decoding of colour television signals according to the pal - standard and method for transmitting color television signals, according to the pal - standard

摘要

In a known device, three-dimensional filterings are carried out in the luminance channel and in the chrominance channel in such a manner that both the luminance and the chrominance component are unambiguously allocated spaces in the three-dimensional frequency space. PAL coding and decoding is effected in conventional manner by means of quadrature modulation and quadrature demodulation, respectively. In the novel device, the loss in bandwidth of the luminance component caused by the three-dimensional filtering is to be reduced. For this purpose, the PAL-modulated chrominance signal is subjected to a multi-dimensional residual side band filtering in the coder. In order to largely reduce or to avoid mutual crosstalk between the colour difference signals at the receiving end, the colour difference signals are low-pass-filtered in the direction of vertical frequencies during the multi-dimensional filtering. PAL coder, PAL decoder, PAL transmission systems. IMAGE