Bandelet representations for image compression

Abstract

Summary form only given, as follows. To improve image representations, it is necessary to take advantage of the geometrical regularity of singularities along edges. Bandelets are orthogonal families, that can be adapted to capture singularities that evolve regularly along smooth geometrical contours, with few non-zero coefficients. They are constructed from one-dimensional foveal wavelets, that are orthogonal one-dimensional functions that approximate signals with a strategy similar to that of the retina. Images are partly represented with bandelet coefficients along edges, plus a residual which is decomposed in a regular two-dimensional wavelet basis. The edge curves are chosen to minimize the error for a given number of nonzero bandelet and wavelet coefficients. They are represented in a one-dimensional wavelet basis. An application to image compression has been compared with JPEG2000.