| 摘要 |
PROBLEM TO BE SOLVED: To decode a bit stream of sequential scanning form with high image quality by interleaving scanning lines of an input signal and coding the result as main and reinforcing signals in the interlacing scanning mode to obtain 1st and 2nd bit streams. SOLUTION: An input image signal in the sequential scanning mode is divided into a main signal and a reinforcing signal in the interlacing scanning mode by a division means 1, 1st and 2nd coded bit streams are generated by 1st and 2nd coding means 2, 3. In the case of decoding, a high level receiver 9 uses 1st and 2nd decoding means 6, 7 which decode respectively each bit stream to reproduce main and reinforcement signals in the interlace scanning mode and uses a synthesis means 8 which synthesizes the decoding outputs to form an output image signal in the sequential scanning mode. The means 1 divides the reinforcement signal not including a low frequency component of a vertical frequency or horizontal frequency so as to suppress power thereby making the image unremarkable. Thus, while image quality is not deteriorated, the coding efficiency of the means 3 is improved. |
