A lattice vector quantizer for generalized Gaussian sources

Author

Chen, Feng ; Gao, Zheng ; Villaseno, John

Author_Institution

Dept. of Electr. Eng., California Univ., Los Angeles, CA, USA

Volume

1

fYear

1995

fDate

23-26 Oct 1995

Firstpage

105

Abstract

A fixed-rate lattice vector quantizer for generalized Gaussian (GG) sources is presented. By using the contour of constant probability of a generalized Gaussian source to bound the integer lattice, this vector quantizer in the limit of high dimension achieves optimal boundary gains for GG sources. Low-complexity techniques for rate control, optimal codevector search and enumeration are developed. This coder achieves 8.60 dB for a generalized Gaussian source with shape parameter of 0.5 at 1 bit/sample (compared with a rate distortion bound of 9.23 dB) and 32.62 dB for the 512×512 “Lena” image at 0.25 bpp without the use of entropy coding. By using two small lookup tables, the nearest codeword search operation can be performed multiply-free and the overall quantization process costs one multiply and a few adds per sample

Keywords

Gaussian processes; image coding; lattice theory; optimisation; rate distortion theory; search problems; table lookup; vector quantisation; GG sources; Lena image; contour of constant probability; dimension; enumeration; fixed-rate lattice vector quantizer; generalized Gaussian sources; integer lattice; lookup tables; low-complexity techniques; optimal boundary gains; optimal codevector search; quantization process; rate control; shape parameter; Bit rate; Costs; Entropy coding; Equations; Lattices; Optimal control; Quantization; Rate-distortion; Shape; Table lookup;

fLanguage

English

Publisher

ieee

Conference_Titel

Image Processing, 1995. Proceedings., International Conference on

Conference_Location

Washington, DC

Print_ISBN

0-8186-7310-9

Type

conf

DOI

10.1109/ICIP.1995.529050

Filename

529050