| 摘要 |
<p>PURPOSE:To reduce the cost of the device by sampling only a signal in a vertical direction at a low frequency, sampling only a signal in a horizontal direction at a high frequency, making the number of samples equal to each other in the low and high frequencies, so as to make the processing quantity equal to each other thereby allowing the hierarchical coder and decoder only to cope with a picture system of different resolution. CONSTITUTION:A vertical sub sampler 2 and a vertical over sampler 7 in place of a 2-dimension are used and a horizontal sub sampler 9 is added instead as a different point from a conventional device. That is, an input signal from a picture input 1 is subjected to 1/2 band control in the vertical direction by the vertical sub sampler 2, compressed by a DCT 3, a quantizer 4 and a variable length coder 5 and outputted as L data 6. Moreover, the sub sampled signal is given to the vertical over sampler 7, in which vertical interpolation is implemented, the sample number is restored to that of the input signal and the result is outputted. A high frequency signal is subjected to 1/2 band in the horizontal direction by the horizontal sub sampler 9, coded by a DCT 10, a quantizer 11 and a variable length coder 12 and the result is outputted as H data 13.</p> |
