A layered motion estimation algorithm is proposed that permits quasi-s
imultaneous motion estimation/segmentation up to a fixed maximum numbe
r of layers. The estimation results in one motion parameter set per la
yer, and a segmentation map that assigns these sets to different parts
of the image (motion layers). Motion in a layer is modelled with at m
aximum four parameters capable of describing pan, tilt and zoom. The c
oncept shows some hierarchy, i.e. a ranking of the motion layers. In t
his way the motion parameter estimation concerning one layer excludes
those parts of the image that have been described by a layer ranked hi
gher in the hierarchy and are not polluted by parts of the image that
are better described by layers ranked lower in the hierarchy. The conc
ept results in a very low operations count. It has been shown to perfo
rm well even in critical scan rate conversion applications, particular
ly in picture rate up-conversion. A variant including three layers has
been scheduled to run in real-time on a Philips TriMedia processor.