INTERPOLATION PROCESSING CIRCUIT FOR SUB-SAMPLED VIDEO SIGNAL

摘要

PURPOSE:To provide video signals without the foldover distortion of a spatial frequency band regardless of the kind of a low-pass filter provided in a sub- sampling circuit on a video signal transmission side in an interpolation processing circuit on a video signal reception side. CONSTITUTION:The video signals vertically or horizontally filtered, band-limited and sub-sampled in a state where inter-frame offsetting is performed in a zigzag stripe shape in the sub-sampling circuit are passed through a transmission system 4 and transmitted to the reception side. The received video signals are zero- interpolated in a zero interpolation part 12. A selector 15 selects the video signals interpolated by a vertical filter 13 when the sub-sampling circuit uses the vertical filter and selects the video signals interpolated by the vertical and horizontal filters 13 and 14 when the sub-sampling circuit uses a two-dimensional filter corresponding to the changeover of a changeover switch by an operator watching a cathode-ray tube for picture reproduction. Thus, improved pictures for which the horizontal straight line of reproducing pictures is not a broken line are reproduced.