Additive And Multiplicative Noise Removal From Medical Images Using Bivariate Thresholding by Dual Tree Complex Wavelet Transform
نویسندگان
چکیده
This paper introduces a technique of bivariate thresholding based dual tree complex Wavelet transform(DTCWT) to remove additive and multiplicative both the noise signals. Since both the noises are different in nature hence it is difficult to remove both the noises by using single filter. Therefore two different filters are required denoise medical images which are corrupted by either of the noises simultaneously. In this paper DTCWT approach is used to denoise medical images. DTCWT based filter removes additive white Gaussian noise (AWGN) effectively. Since speckle noise is multiplicative in nature; it is converted into logarithmic transform before apply wavelet transform. Bivariate thresholding function is used which is soft thresholding and it outperforms other thresholding techniques.
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