关键词: 医学超声图像去噪, 小波变换, 数据融合

Abstract: There are inherent speckle noises in the medical ultrasound image. They degradation image quality and affect doctor's diagnosis. Classical speckle suppression method can restrain them with the loss of many image edge details. In this paper, a speckle suppression method for medical ultrasound image based on data fusion and wavelet transform was presented. Firstly, logarithmic transform was carried out to the medical ultrasound image. Multiplicative noises were transformed into additive ones. Secondly, two original images from the same source with different noises were decomposed each by wavelet transform. For low frequency image, the new approximation coefficients were obtained by the weighted mean value of the approximation coefficients in two original images. For high frequency sub-band images, the new coefficients were selected by those coefficients with bigger absolute values in two original images. The details in high frequency image were reserved furthest. Finally, the denoised image was reconstructed by the inverse wavelet transform using the new wavelet coefficients and the exponential transform was processed. The results show speckle noises in the original images are removed efficiently and the image edge details are reserved.

Key words: medical ultrasound image denoising, wavelet transform, data fusion