Block wavelet transforms for image 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...

Block Transforms in Progressive Image Coding

Wavelet-Based Fractal Transforms for Image Coding with No Search

The compression performance of fractal image coding is considered using the wavelet-based fractal coder with no search or classi cation of the domain blocks. A new partitioning scheme is introduced as a variant of earlier schemes which further improves the compression performance. The Wavelet-Based Fractal Transform (WBFT) links the theory of multiresolution analysis (MRA) with iterated functio...

Adaptive transforms for image coding using spatially varying wavelet packets

We introduce a novel, adaptive image representation using spatially varying wavelet packets (WPs), Our adaptive representation uses the fast double-tree algorithm introduced previously (Herley et al., 1993) to optimize an operational rate-distortion (R-D) cost function, as is appropriate for the lossy image compression framework. This involves jointly determining which filter bank tree (WP freq...

Modifying integer wavelet transforms for scalable near-lossless image coding

In near-lossless image coding, each reconstructed pixel of the decoded image differs from the corresponding one in the original image by not more than a pre-specified value δ. Such schemes are mainly based on predictive coding techniques, which are not capable of scalable decoding. Lossless image coding with scalable decoding is mainly based on integer wavelet transforms. In this paper, methods...