检索结果-南通市图书馆

Combining IFS and VQ in fractal image coding

在线全文

学校读者我要写书评

暂无评论

引用

The Journal of China Universities of Posts and Telecommunications 2000年第1期7卷 26-30页

作者： HUANG Yi, SUN Hai-an (Information Engineering Department, Nanjing University of Posts and Telecommunications, Nanjing 210003, P.R.China) Information Engineering Department Nanjing University of Posts and Telecommunications Nanjing 210003 P.R.China

A novel paradigm for fractal coding selectively corrects the fractal code for selected domain blocks with an image-adaptive VQ codebook. The codebook is generated from the initial uncorrected fractal code and is, ther... 详细信息

关键词： fractal image coding vector quantization interacted function systems

Efficient Quadtree based fractal image coding Scheme in Wavelet Transform Domain *

在线全文

学校读者我要写书评

暂无评论

引用

Journal of Southeast University(English Edition) 1998年第1期14卷 35-40页

作者：高西奇洪波张辉何振亚东南大学无线电工程系

This paper presents an efficient quadtree based fractal image coding scheme in wavelet transform domain based on the wavelet based theory of fractal image compression introduced by Davis. In the scheme, zerotrees of wavelet coefficients are used to reduce the number of domain blocks, which leads to lower bit cost required to represent the location information of fractal coding, and overall entropy constrained optimization is performed for the decision trees as well as for the sets of scalar quantizers and self quantizers of wavelet subtrees. Experiment results show that at the low bit rates, the proposed scheme gives about 1 dB improvement in PSNR over the reported results.

关键词： fractal image coding wavelet transform quadtree

A HIGH SPEED ADAPTIVE fractal image coding ALGORITHM USING FLEXIBLE CLASSIFICATION TECHNIQUE

在线全文

学校读者我要写书评

暂无评论

引用

Wuhan University Journal of Natural Sciences 1998年第2期3卷 146-146页

作者： Zhang Liang Li Weihua Wang Qiao Wuhan University College of Computer Science and Technology Wuhan China (GRID:grid.49470.3e) (ISNI:***)

Traditionally, fractal image compression suffers from lengthy encoding time in measure ofhours. In this paper, combined with characteristlcs of human visual system, a flexible classification technique is proposed. This yields a corresponding adaptive algorithm which can cut down the encoding timeinto second's magnitude. Experiment results suggest that the algorithm can balance the overall encodingperformance efficiently, that is, with a higher speed and a better PSNR gain.

关键词： image coding fractal image coding iterated function system (IFS) partitioned iterated function system (PIFS) characteristics of human visual system