摘要 |
<p>Compatibility improvement apparatus for the use within standard MAC decoders when receiving HDMAC signals. Due to the 4-field encoding technique combined with line shuffling, the compatible pictures suffer from edge crawling and dot pattern artefacts with a flicker frequency of 12.5 Hz. Within moving picture areas the viewer perceives a motion judder which results from the synthetic interlace applied within the 40ms transmission mode. A D2-MAC standard decoder is modified by including a compatibility improvement filter. This filter is motion adaptive and will be switched by the motion information of the DATV signal. Advantageously this filter is suited, too, for standard decoders which provide progressive scan lines at their output.</p> |