Indexing the output points of an LBVQ used for image transform coding

Author

Khataie, Manijeh ; Soleymani, M.R.

Author_Institution

Dept. of Electr. & Comput. Eng., Concordia Univ., Montreal, Que., Canada

Volume

9

Issue

5

fYear

2000

fDate

5/1/2000 12:00:00 AM

Firstpage

827

Lastpage

833

Abstract

A new method for indexing the points of a lattice-based vector quantizer (LBVQ) used to quantize the DCT coefficients of images is presented. With this method, a large number of lattice points can be selected as codewords. As a result, the quality of the compressed data can be very high. The problem is that the large number of points results in a high bit rate. To reduce the bit rate, a shorter representation is assigned to the more frequently used lattice points. These points are grouped and a prefix code is used to index these lattice points. Our method outperforms JPEG, particularly, in the case of images with high frequency components

Keywords

discrete cosine transforms; image coding; transform coding; vector quantisation; DCT coefficients quantization; JPEG; LBVQ; bit rate reduction; codewords; compressed data quality; high bit rate; high frequency components; image transform coding; lattice-based vector quantizer; output points indexing; prefix code; Bit rate; Discrete cosine transforms; Discrete transforms; Dynamic range; Entropy; Frequency; Image coding; Indexing; Lattices; Transform coding;

fLanguage

English

Journal_Title

Image Processing, IEEE Transactions on

Publisher

ieee

ISSN

1057-7149

Type

jour

DOI

10.1109/83.841529

Filename

841529