A Multilevel Energy-based Quantization Scheme
نویسندگان
چکیده
A vector quantizer maps N -dimensional vectors in the domain Ω ⊂ R into a finite set of vectors {zi}i=1 . Each vector zi is called a code vector or a codeword, and the set of all the codewords is called a codebook. A special, yet popular, quantization scheme is given by the Voronoi tessellation associated with some codewords {zi} , also called generators. A Voronoi tessellation for the given generating points {zi}i=1 ⊂ Ω refers to the tessellation of a given domain Ω by the Voronoi regions {Vi}i=1 where, for each i , the Voronoi region Vi consists of all points in Ω that are closer to zi than to the other generating points. For a density function ρ defined on Ω , we define the centroids, or mass centers, of the regions {Vi}i=1 by zi = ( ∫
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