WAVELET-BASED MEDICAL IMAGE COMPRESSION USING EZW: OBJECTIVE AND SUBJECTIVE EVALUATIONS

2004 ◽  
Vol 04 (01) ◽  
pp. 93-110 ◽  
Author(s):  
YIN FEN LOW ◽  
ROSLI BESAR

Recently, the wavelet transform has emerged as a cutting edge technology within the field of image compression research. Wavelet methods involve overlapping transforms with varying-length basis functions. This overlapping nature of the transform alleviates blocking artifacts, while the multi-resolution character of the wavelet decomposition leads to superior energy compaction and perceptual quality of the decompressed image. Embedded zerotree wavelet (EZW) coder is the first algorithm to show the full power of wavelet-based image compression. The main purpose of this paper is to investigate the impact and quality of orthogonal wavelet filter in compressing medical image by using EZW. Meanwhile, we also look into the effect of the level of wavelet decomposition towards compression efficiency. The wavelet filters used are Haar and Daubechies. The compression simulations are done on three modalities of medical images. The objective (based on PSNR) and subjective (perceived image quality) results of these simulations are presented.

Author(s):  
Yin Fen Low ◽  
Rosli Besar

Recently, the wavelet transform has emerged as a cutting edge technology, within the field of image compression research. The basis functions of the wavelet transform are known as wavelets. There are a variety of different wavelet functions to suit the needs of different applications. Among the most popular wavelets are Haar, Daubechies, Coiflet and Biorthogonal, etc. The best wavelets (functions) for medical image compression are widely unknown. The purpose of this paper is to examine and compare the difference in impact and quality of a set of wavelet functions (wavelets) to image quality for implementation in a digitized still medical image compression with different modalities. We used two approaches to the measurement of medical image quality: objectively, using peak signal to noise ratio (PSNR) and subjectively, using perceived image quality. Finally, we defined an optimal wavelet filter for each modality of medical image.


2009 ◽  
Vol 09 (04) ◽  
pp. 511-529
Author(s):  
ALEXANDER WONG

This paper presents PECSI, a perceptually-enhanced image compression framework designed to provide high compression rates for still images while preserving visual quality. PECSI utilizes important human perceptual characteristics during image encoding stages (e.g. downsampling and quantization) and image decoding stages (e.g. upsampling and deblocking) to find a better balance between image compression and the perceptual quality of an image. The proposed framework is computationally efficient and easy to integrate into existing block-based still image compression standards. Experimental results show that the PECSI framework provides improved perceptual quality at the same compression rate as existing still image compression methods. Alternatively, the framework can be used to achieve higher compression ratios while maintaining the same level of perceptual quality.


Modern radiology techniques provide crucial medical information for radiologists to diagnose diseases and determine appropriate treatments. Hence dealing with medical image compression needs to compromise on good perceptual quality (i.e. diagnostically lossless) and high compression rate. The objective also includes finding out an optimum algorithm for medical image compression algorithm. The objective is also focused towards the selection of the developed image compression algorithm, which do not change the characterization behavior of the image.


Author(s):  
Cristina Juarez Landin ◽  
Magally Martinez Reyes ◽  
Anabelem Soberanes Martin ◽  
Rosa Maria Valdovinos Rosas ◽  
Jose Luis Sanchez Ramirez ◽  
...  

Author(s):  
Rongbing Zhou ◽  
Mingkai Huang ◽  
Shuyi Tan ◽  
Lijun Zhang ◽  
Du Chen ◽  
...  

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