SUB-SAMPLING TRANSMISSION SYSTEM FOR IMPROVING TRANSMISSION PICTURE QUALITY IN TIME-VARYING PICTURE REGION OF WIDE-BAND COLOR PICTURE SIGNAL.

摘要

A sub-sampling transmission system in the time-varying picture region of a wide-band color picture signal for a high-definition telecast, in which the resolution and overall picture quality of a reproduced color time-varying picture are improved by using the following picture signal processings, instead of a usual line offset sub-sampling every field in a narrow-band transmission of the color picture signal, for which the resolution of the time-varying picture is made low in comparison with a static picture subjected to an offset sub-sampling using the sampling pattern cycled every two frames. In the picture signal processings, an offset sub-sampling between the fields is applied to a color difference signal in the time-varying picture region. Also, the signal processing, which includes a frequency band limitation for preventing an aliasing accompanied by the sub-sampling from generating, and an interpolation when reproducing, is performed between the fields in the form of it being completed every frame. Further, with respect to the time-varying picture region of its movement in the vertical direction being small, a similar sub-sampling and signal processing are performed for its luminance signal too.