Analysis of the DCT coefficient distributions for document coding

Author

Lam, Edmund Y.

Author_Institution

Dept. of Electr. & Electron. Eng., Univ. of Hong Kong, China

Volume

11

Issue

2

fYear

2004

Firstpage

97

Lastpage

100

Abstract

It is known that the distribution of the discrete cosine transform (DCT) coefficients of most natural images follow a Laplacian distribution, and this knowledge has been employed to improve decoder design. However, such is not the case for text documents. In this letter, we present an analysis of their DCT coefficient distributions, and show that a Gaussian distribution can be a realistic model. Furthermore, we can use a generalized Gaussian model to incorporate the Laplacian distribution found for natural images.

Keywords

Gaussian distribution; Laplace transforms; discrete cosine transforms; document image processing; image coding; transform coding; DCT coefficient distribution analysis; Laplacian distribution; decoder design; discrete cosine transform; document coding; image coding; natural image analysis; probability statistics; realistic Gaussian distribution model; text document processing; Discrete cosine transforms; Gaussian distribution; Gray-scale; Image analysis; Image coding; Laplace equations; Maximum likelihood decoding; Stochastic processes; Text analysis; Transform coding;

fLanguage

English

Journal_Title

Signal Processing Letters, IEEE

Publisher

ieee

ISSN

1070-9908

Type

jour

DOI

10.1109/LSP.2003.821789

Filename

1261947