| 摘要 |
PURPOSE:To compress a video signal without damaging subjective picture quality by limiting bands different at every field against the video signal. CONSTITUTION:An input analog luminance signal Y and color difference signals R-Y and B-Y are quantized by A/D converters 1-3. The only picture data part of each field from among the output of the converters 1-3 is extracted in an effective area extracting circuit 9. Horizontal sampling frequency is converted in the luminance signal Y, the color difference signals R-Y/B-Y, and frequency conversion circuits 10, 13, 16 from the circuit 9. On the other hand, the signals Y, R-Y, and B-Y outputted from the circuit 9 are inputted to scanning line conversion circuits 11, 14, 17 to convert the number of scanning lines. Changeover switches 12, 15, 18 are outputted by switching the output of the circuits 10, 13, 16 and the output of the circuits 11, 14, 17 at every field. The signal outputted from the switches 12, 15, 18 are inputted to a high efficiency encoder 7, further data-compressed. |
