A method and apparatus for detecting and correcting motion artifacts in
interlaced video signal converted for progressive video display. A
correction is applied where interlaced video material is determined to
originate from film source, thereby having been converted to video using
a process known as 3-2 pulldown. Where the video material is not a result
of the 3-2 pulldown process, a check is made for the presence of "pixel
motion" so that corrections may be applied to smooth out the pixel
motion. To determine 3-2 pulldown or field motion, a video field is
compared to the field prior to the previous field to generate field
error. Field errors are generated for five consecutive fields and a local
minimum error repeated every five fields indicate the origination of the
video material from film source using the 3-2 pulldown process. Upon
confirmation of 3-2 pulldown, the video material is modified to correct
for the mixing of two film frames into one interlaced video frame by
assuring that the two fields of the de-interlaced video frame contain
data from the same film frame. Where the video material did not originate
from a film source, but pixel motion is detected, the pixel motion is
smoothed out by an averaging method. The odd and even fields of the
resulting video data are subsequently combined to form a progressive
video material.