Advanced Block Matching Algorithms
There are a number of complex motion compensation techniques that have the potential to offer performance improvements over conventional block matching techniques. They are based on the same principles as the motion compensation techniques discussed in the previous chapter but they take a more general view of the motion compensation problem.
Hierarchical Block Matching Algorithms
Hierarchical block matching techniques attempt to combine the advantages of large blocks with those of small blocks. Large blocks are more likely to track actual motion than small ones and thus are less likely to converge on local minima. Hierarchical block matching algorithms exploit the motion tracking capabilities of large blocks and use their motion vectors as a starting points for searches for small blocks.
[More about on hierarchical BMAs
Multidimensional Search Spaces
Simple block based motion compensation does not compensate for changes due to illumination variation, object rotation or motion in directions other than that parallel to the camera plane. Multi-dimensional motion compensation schemes attempt to compensate for these additional factors.
[More on multidimensional serach spaces
[return to BMAs part2
© Colin E. Manning 1996