期刊名称：International Journal of Engineering and Computer Science
印刷版ISSN：2319-7242
出版年度：2015
卷号：4
期号：5
页码：11871-11875
出版社：IJECS
摘要：Ultrasonography is regarded as one of the best and most powerful techniques for diagnostic examination and analysisof various imaging organs and soft tissue structures present in human body. It is used for visualizing muscles, their shape and size,their structure and any pathological lesions. The usefulness of ultrasound imaging is degraded by the existence of a signaldependent noise called as speckle noise. This speckle pattern is further dependent on the structure of the imaging tissue as well ason various imaging parameters. In the proposed work, a novel approach has been suggested with an adaptive threshold estimatorfor image denoising in wavelet domain based on the modeling of different sub-band coefficients at different stages in ultrasoundimaging systems. The proposed method has been found to be more adaptive as the estimated parameters for threshold valuedepends on image sub-band data. The calculated threshold value depends upon scale parameter, noise variance and standarddeviation corresponding to each sub-band of the noisy image. The scale parameter is dependent upon the sub-band size andnumber of decompositions. The experimental results carried out on many ultrasound test images outperformed both qualitativelyand quantitatively, when compared with some other existing denoising techniques like Normal Shrink, Median Filter, and WienerFilter. The clinical validation by a radiologist of the results has also been performed
关键词：Ultrasonography; Standard Deviation;Wavelet Thresholding; Noise Variance
