<abstract xmlns="http://www.w3.org/1999/xhtml"><p>A novel semilogarithmic hybrid quantizer for non-uniform scalar quantization of Laplacian source, which consist of uniform quantizer and companding quantizer is introduced. Uniform quantizer has unit gain in area around zero. Companding quantizer is defined with a novel logarithm characteristic. Also an analysis of classic semilogarithmic A-law for various values of A parameter is provided. Comparation with classic semilogarithmic A-law is performed. The main advantage of hybrid quantizer is that number of representation levels for both uniform and companding quantizer are not unambiguously determined function of the A parameter value, as it is the case with classic semilogarithmic A companding characteristic. It is shown that by using hybrid quantizer, average of signal-to-quantization noise ratio SQNR quality obtained by using classic A companding law can be overachieved for 0.47 dB. Numbers of representation levels of hybrid quantizer are adapted to the input signal variances, in order to achieve high SQNR in a wide range of signal volumes (variances). By using this adaptation higher average SQNR quality of 2.52 dB could be achieved compared to classic A companding law. Forward adaptation of hybrid quantizer is analyzed and obtained performances correspond to adaptive classic A companding law case but possible advantage arises in simpler practical realization of hybrid quantizers. Obtained performances correspond to classic A-law companding case, because during the adaptation process, optimal values of parameter A are chosen. For each other A parameter values proposed hybrid quantizer provides better results. For value of A = 50 hybrid model has higher SQNR value for 0.79 dB</p></abstract>

A novel semilogarithmic hybrid quantizer for non-uniform scalar quantization of Laplacian source, which consist of uniform quantizer and companding quantizer is introduced. Uniform quantizer has unit gain in area around zero. Companding quantizer is defined with a novel logarithm characteristic. Also an analysis of classic semilogarithmic A-law for various values of A parameter is provided. Comparation with classic semilogarithmic A-law is performed. The main advantage of hybrid quantizer is that number of representation levels for both uniform and companding quantizer are not unambiguously determined function of the A parameter value, as it is the case with classic semilogarithmic A companding characteristic. It is shown that by using hybrid quantizer, average of signal-to-quantization noise ratio SQNR quality obtained by using classic A companding law can be overachieved for 0.47 dB. Numbers of representation levels of hybrid quantizer are adapted to the input signal variances, in order to achieve high SQNR in a wide range of signal volumes (variances). By using this adaptation higher average SQNR quality of 2.52 dB could be achieved compared to classic A companding law. Forward adaptation of hybrid quantizer is analyzed and obtained performances correspond to adaptive classic A companding law case but possible advantage arises in simpler practical realization of hybrid quantizers. Obtained performances correspond to classic A-law companding case, because during the adaptation process, optimal values of parameter A are chosen. For each other A parameter values proposed hybrid quantizer provides better results. For value of A = 50 hybrid model has higher SQNR value for 0.79 dB

Semi–logarithmic and hybrid quantization of Laplacian source inwide range of variances

Mathematical institute of Serbian Academy of Science and Art, Kneza Mihaila 36, 11001 Belgrade, Serbia

Faculty of Electrical Engineering, University of Niˇs, Aleksandra Medvedeva 14, Niˇs, 18000, Serbia

Faculty of Natural Sciences and Mathematics, Lole Ribara 29, Kosovska Mitrovica, 38200, Serbia

Journal of Electrical Engineering

A novel semilogarithmic hybrid quantizer for non-uniform scalar quantization of Laplacian source, which consist of uniform quantizer and companding quantizer...

Semi–logarithmic and hybrid quantization of Laplacian source inwide range of variances

Pubblicato online: 29 dic 2012

Pagine: 386 - 391

DOI: https://doi.org/10.2478/v10187-012-0057-z

Parole chiave
hybrid semilogarithmic quantizer, forward adaptive quantization, Laplacian source

This content is open access.

Semi–logarithmic and hybrid quantization of Laplacian source inwide range of variances

Pubblicato online: 29 dic 2012

Pagine: 386 - 391

DOI: https://doi.org/10.2478/v10187-012-0057-z

Parole chiavehybrid semilogarithmic quantizer, forward adaptive quantization, Laplacian source

This content is open access.

Parole chiave
hybrid semilogarithmic quantizer, forward adaptive quantization, Laplacian source