A unique method for chroma vertical upsampling used, for example, for
conversion of the "4:2:0" format chroma information used in many
applications of digital video, to the "4:2:2" or "4:4:4" format, is
presented. This conversion is required so that video encoders can effect
the display of this chroma information with a minimum of visible
artifacts. The present invention carries out chroma vertical upsampling
on a pixel by pixel basis. This chroma vertical upsampling is performed
as a function of the amount of motion associated with each pixel as
detected between 2 or more fields, and the field, frame and progressive
sequence characteristics of the incoming video signal data.