Abstract: A pixel interpolation system for developing progressive line scan video from two interlaced fields of video. An intrafield pixel value is determined by averaging the pixel in the line above and the line below the desired pixel. A motion value is determined by averaging the pixels in the line above and the line below the desired pixel in corresponding fields one frame before and one frame after the desired pixel, subtracting the intrafield pixel value therefrom and comparing these values with the difference of the pixels in the same spatial relationship as the desired pixel, but one field earlier and one field later. The motion value is taken as the largest of the individual values that are determined. An interfield pixel value is determined by comparing the intrafield pixel value with the corresponding pixels in the previous and subsequent frames. The motion value is used to proportion the intrafield and interfield pixel values to generate the desired pixel.

Abstract: Apparatus for converting a digital video signal between two different formats, such as interlaced field and non-interlaced progressive frame, and which avoids filtering and sub-sampling of portions of the video data which are the same in either format. For conversion from interlaced field to progressive frame, only alternate fields of the signal are subjected to digital filtering. The filtered fields are then combined with the non-filtered fields, which are subjected only to an equivalent delay, to derive averaged frames which constitute a progressive frame video signal. For the reverse conversion, alternate scan lines of each frame are sub-sampled and averaged to derive a field which is then interlaced with a field formed by the remaining scan lines of such frame, thereby deriving an interlaced field video signal.