Video signal converting apparatus with reduced processing for aliasing interference.

摘要

A video signal conversion apparatus for converting high definition television signals band-width compressed by offset sub-sampling to a conventional standard television signal while removing aliasing interference caused by offset sub-sampling and using less memory capacity than is conventionally required is provided. The image of the sub-sampled signal is restored from the sampling points in the current field by an intra-field interpolation circuit (2), and the number of scan lines is reduced to the same number in the standard television signal format by a scan line number conversion circuit (3). Half of the pixels in the current field are then substituted into the signal for the one previous frame for inter-frame interpolation by a signal selector (4) which alternately selects a signal from the scan line number conversion circuit (3) and a signal from field memories (5 and 6), and a time-base operation for removing aliasing interference at the standard television signal rate is executed. <IMAGE>