POLYPARAMETRIC BLOCK CODING

Block truncation coding with entropy coding

Block Truncation Coding (BTC) is a simple and fast image compression algorithm wich achieves constant bit rate of 2.0 bits per pixel. The method is however suboptimal. In the present paper we propose a modification of BTC in which the compression ratio will be improved by coding the quantization data and the bit plane by arithmetic coding with an adaptive modelling scheme. The results compare f...

Block-based Subband Coding

Adaptive Wavelet Image Block Coding

In this paper a new approach for adaptive wavelet image coding is introduced. Based on an adaptive quadtree image-block partition (similar to fractal coding) the diierent image blocks may be compressed independently in an adaptive manner. In order to adapt to local image statistics and features we present several possibilities how to optimize the transform part of a wavelet image block-coder. A...

Coding with variable block maps

In this article we study a special class of sliding block maps that we call variable block maps.We characterize the subsets of finite and infinite sequences that can be obtained as the image of another subset of symbolic sequences by a variable block map. On the other way, we show that the coding process induced by such kind of block maps can be reversed, even with partial knowledge about the v...

Colour image coding scheme using absolute moment block truncation coding and block prediction technique

A predictive colour image compression scheme based on absolute moment block truncation coding is proposed. In this scheme, the high correlations among neighbouring image blocks are exploited by using the similar block prediction technique. In addition, the bit plane omission technique and the coding of quantisation levels are used to cut down the storage cost of smooth blocks and complex blocks...