| 摘要 |
PURPOSE:To use a recording medium in common by reducing a difference between HDTV (EDTV) and SDTV in information quantity without the need for a complicated device configuration. CONSTITUTION:A signal converter 12 of a coder 10 applied sub-sampling to an SDTV signal, and signal converters 22, 24 apply vertical sub-sampling and horizontal sub-sampling to a difference signal obtained by a subtractor 14. Signal inverse converters 38, 40, 42 apply up-sampling to the signal subjected to sub-sampling. Since the visual characteristic with respect to resolution is high in horizontal and vertical directions but not so high in an oblique direction, the information quantity is reduced while the reduction in the visual resolution is suppressed by utilizing horizontal and vertical components of a difference signal. |
