ARUP; ISBN: 978-0-9562121-5-3 - CMBBE 2012 - Cardiff University

In this paper two multi-scale methods were tested and compared for enhancing visual
quality of ultrasound images. Those methods were proven to be very efficient to treat
multiplicative noise and reduce speckle in ultrasound images. Several studies prove that
WST was among the best methods for ultrasound images. The contrast method using
median filtering was applied recently on ultrasound images and proves to give very
good results. To date, WST and contrast have not been compared to each other using
ultrasound images where a lot of variation exists in the background. The overall
quantitative assessment in terms of homogeneity inside the ROI, contour preservation
and error distribution indicated that WST provided a better overall improvement for
image segmentation.
A qualitative assessment of few ultrasound images performed by a diagnosis expert
(using some areas of interest) confirms that the WST method shows a much better
segmentation.
This study proves that wavelet filtering using soft-thresholding is an excellent tool for
despeckling of digital ultrasound images as a preprocessing step to unsupervised
segmentation of ultrasound images.
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