Optimization of Quantizer’s Segment Threshold Using Spline Approximations for Optimal Compressor Function

Lazar Velimirović, Zoran Perić, Miomir Stanković, Jelena Nikolić

Department of Telecommunications, Faculty of Electronic Engineering, University of Ni?, Ni?, Serbia.
Mathematical Department, Faculty of Occupational Safety, University of Ni?, Ni?, Serbia.
Mathematical Institute of the Serbian Academy of Sciences and Arts, Belgrade, Serbia.

DOI: 10.4236/am.2012.330201                

Abstract

In this paper, the optimization of quantizer’s segment threshold is done. The quantizer is designed on the basis of approximative spline functions. Coefficients on which we form approximative spline functions are calculated by minimization mean square error (MSE). For coefficients determined in this way, spline functions by which optimal compressor function is approximated are obtained. For the quantizer designed on the basis of approximative spline functions, segment threshold is numerically determined depending on maximal value of the signal to quantization noise ratio (SQNR). Thus, quantizer with optimized segment threshold is achieved. It is shown that by quantizer model designed in this way and proposed in this paper, the SQNR that is very close to SQNR of nonlinear optimal companding quantizer is achieved.

Keywords

Optimization of Quantizer’s Segment Threshold; Mean Square Error; Second-Degree Spline Functions; Compressor Function

Conflicts of Interest

The authors declare no conflicts of interest.

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