Using Complex Wavelet Transform and Bilateral Filtering for Image Denoising

The bilateral filter is a useful nonlinear filter which without smoothing edges, it does spatial averaging. In the literature, the effectiveness of this method for image denoising is shown. In this paper, an extension of this method is proposed which is based on complex wavelet transform. In fact, the bilateral filtering is applied to the low-frequency (approximation) subbands of the decomposed image using complex wavelet transform, while the thresholding approach is applied to the high frequency subbands. Using the bilateral filter in the complex wavelet domain forms a new image denoising framework. Experimental results for real data are provided, by which one can see the effectiveness of the proposed method in eliminating noise.

A New Method for Removing the Moire' Pattern from Images

During the last decades, denoising methods have attracted much attention of researchers. The conventional method for removing the Moire' pattern from images is using notch filters in the Frequency-domain. In this paper a new method is proposed that can achieve a better performance in comparison with the traditional method. Median filter is used in some part of spectrum of noisy images to reduce the noise. At the second part of this paper, to demonstrate the robustness of the proposed method, it is implemented for some noisy images that have moire' pattern. Experiments on noisy images with different characteristics show that the proposed method increases the PSNR values compared with previous methods.