To solve speckle noise in medical ultrasound images

a denoising method is proposed based on rough set and wavelet.This method

pending ultrasound image is partitioned into several sub-images based on equivalence relation in rough set

then logarithm transform for each sub-image is operated and wavelet decomposition is accomplished

wavelet coefficients are processed by adaptive threshold function.The denoised sub-images are obtained by wavelet inverse transform and exponential transform.The final denoising image is obtained by overlying denoised sub-images.Experimental results show that the proposed method is more effective in removing the noise while preserving more edges and detail features.