Image Compression: A Survey <s> Reduced memory and line-based wavelet compression (LBRMBIC): <s> This paper addresses the problem of low memory wavelet image compression. While wavelet or subband coding of images has been shown to be superior to more traditional transform coding techniques, little attention has been paid until recently to the important issue of whether both the wavelet transforms and the subsequent coding can be implemented in low memory without significant loss in performance. We present a complete system to perform low memory wavelet image coding. Our approach is "line-based" in that the images are read line by line and only the minimum required number of lines is kept in memory. There are two main contributions of our work. First, we introduce a line-based approach for the implementation of the wavelet transform, which yields the same results as a "normal" implementation, but where, unlike prior work, we address memory issues arising from the need to synchronize encoder and decoder. Second, we propose a novel context-based encoder which requires no global information and stores only a local set of wavelet coefficients. This low memory coder achieves performance comparable to state of the art coders at a fraction of their memory utilization. <s> BIB001 </s> Image Compression: A Survey <s> Reduced memory and line-based wavelet compression (LBRMBIC): <s> This paper presents a contrast-based quantization strategy for use in lossy wavelet image compression that attempts to preserve visual quality at any bit rate. Based on the results of recent psychophysical experiments using near-threshold and suprathreshold wavelet subband quantization distortions presented against natural-image backgrounds, subbands are quantized such that the distortions in the reconstructed image exhibit root-mean-squared contrasts selected based on image, subband, and display characteristics and on a measure of total visual distortion so as to preserve the visual system's ability to integrate edge structure across scale space. Within a single, unified framework, the proposed contrast-based strategy yields images which are competitive in visual quality with results from current visually lossless approaches at high bit rates and which demonstrate improved visual quality over current visually lossy approaches at low bit rates. This strategy operates in the context of both nonembedded and embedded quantization, the latter of which yields a highly scalable codestream which attempts to maintain visual quality at all bit rates; a specific application of the proposed algorithm to JPEG-2000 is presented. <s> BIB002
Approach for line based wavelet transforms and it divides memory which is to be consumed in two different classes that is filtering memory and synchronization memory. Entropy coding algorithm that can merge with line based transform with very low memory consumption. It is also experimentally shown competitive performance with image coders. This algorithm is better with respect to memory usage and computations BIB001 . Dynamic contrast based quantization: Strategy for the purpose of visual quality restoration has been proposed at any bit rate. For every DWT sub band quantizer size is estimated. On the outcome of psychophysical experiments contrast are chooses applied by using threshold and sub band threshold targets constitute and against many natural image maskers of wavelet sub band quantization distortions presented BIB002 .