Frequency and spatially adaptive wavelet packets
نویسندگان
چکیده
posed both spatially (S) and spectrally (F). The spatial decomposition is carried out using a quad-tree split. Since the spatial partitions do not overlap, this segmentation allows the four children nodes to be further analyzed independently. The frequency decomposition is performed using a four channel quadrature mirror filter (QMF) bank. This produces a library of wavelet packet bases which consist of orthonormal functions that are easily constructible from a single filter kernel [2]. An element of the wavelet packet basis may be identified completely by its tree position and original filter kernel. This characteristic has made wavelet packets extremely tractable for image compression.
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