Analyze image into 2-d cosine packet coefficients
coef = FPT2_CP(basis,img,D)
Quadtree selecting cosine packet basis
2-d image to be transformed into basis
maximum depth of tree
2-d cosine packet coeffts in given basis
Once a cosine packet basis has been selected (presumably via Best2dBasis), this function may be used to expand a given image in that basis.