An encoder includes a segmenter that segments a reference frame, assigning some
or all of the pixels of the reference frame to segments based on pixel color values
and/or pixel location. A kinetic information generator generates kinetic information
that relates regions of a nonkey frame to segments of the reference frame as indicated
by the segmentation. A decoder includes its own segmenter that segments at least
a part of the reference frame extracted from the compressed video data, thereby
eliminating the need for the encoder to include all of the segmentation in the
compressed video data. The decoder includes a nonkey frame generator that regenerates
a nonkey frame using kinetic information about the nonkey frame from the compressed
video data and using at least a part of the segmentation of the reference frame
generated by the decoder's segmenter. The encoder segmentation and decoder segmentation
can be the same or different.