Image Denoising Using Wavelets: Application in Medical Imaging - Advances in Heuristic Signal Processing and Applications - page 305

Fig. 13.20 Denoising of an
echographic image for K = 2

and for K = 4

Fig. 13.21 Denoising of an
echographic image for K = 3

in noise suppressing in medical echography and in magnetic resonance imaging. In
these applications, the proposed method clearly surpasses spatially-adaptive algo-
rithm, in terms of quantities measures of performance (SNR, for example) as well
as in terms of visual quality of images.
Matlab and CC codes used in denoising are available from: http://telin.ugent.be/
~sanja/ .

13.4.2.2 Echography Illustration

Figure 13.20 illustrates an example of gradual speckle-type noise suppression in an
echographic image. This figure depicts the results of processing with a 5 5 window

for various values of tuning parameter K . These results show that the increase in K
produces strong suppression of background noise or texture by raising the intensity
levels of the image. Although, from Fig. 13.21 ,for K

×

= ×

3 window of
analysis, denoising seems optimal, the fact remains that only the trained eye of the
medical expert can make a decision as to the quality of the echographic image, based
on the extracted and interpreted information.

3 and a 3