Tree Approximation and Image Compression

Thursday, October 19, 2000 - 11:00am - 12:00pm
Keller 3-180
Ingrid Daubechies (Princeton University)
Joint work with A. Cohen, W. Dahmer and R. DeVore studied tree approximations and used the results to build a practical coder that gives a performance similar to existing state-of-the-art coders. We derive certain optimality results for our concrete tree approximation algorithms. On the other hand, because the tree structure is known not to be optimal for images, this also points to shortcomings of state-of-the-art coders, which use a similar tree 'philosophy'. In addition, we discuss some adaptivity properties of our tree coder, useful when parts of very large images need to be examined.