Contractivity of fractal transforms for image coding
نویسنده
چکیده
Indexing terms: Coding, Image processing, Fractal transforms In this letter the contractivity of existing fractal transforms for use in image compression schemes is examined. The coding process is described as nonlinear transformation in the finite dimensional euclidean vector space. We derive sufficient conditions for contractivity based on the spectral norm and the spectral radius of the transformation matrix. As a result bounds for the encoding parameters can be formulated which are tighter than the ones known so far.
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