Discrete Wavelet Transform (DWT) has demonstrated far superior to previous Discrete Cosine Transform (DCT) and standard JPEG in natural as well as medical image compression. Due to its localization properties both in special and transform domain, the quantization error introduced in DWT does not propagate globally as in DCT. Moreover, DWT is a global approach that avoids block artifacts as in t...

The key to medical image denoising technique is to remove the noise while preserving important features. Non-local mean filtering and bilateral filtering are commonly used procedures for medical image denoising. In this paper analysis and comparison of spatial as well as frequency domain methods including bilateral filtering , non-local mean filtering, wavelet thresholding, contourlet threshold...

In this paper, we analyze and compare the performance of fusion methods based on four different transforms: i) wavelet transform, ii) curvelet transform, iii) contourlet transform and iv) nonsubsampled contourlet transform. Fusion framework and scheme are explained in detail, and two different sets of images are used in our experiments. Furthermore, eight different performancemetrics are adopte...

We propose a new scheme, named contourlet, that provides a flexible multiresolution, local and directional image expansion. The contourlet transform is realized efficiently via a double iterated filter bank structure. Furthermore, it can be designed to satisfy the anisotropy scaling relation for curves, and thus offers a fast and structured curvelet-like decomposition. As a result, the contourl...

Abstract: We propose a block image compressive sensing algorithm based on interleaving extraction in Contourlet domain to improve the performance of image sparse representation and quality of reconstructed images. First, we propose the interleaving extraction scheme and partition an image into several sub-images using interleaving extraction. Second, we represent the sub-images in Contourlet do...

In this paper, we propose a new robust hybrid watermarking technique based on recently introduced contourlet transform and singular value decomposition. After applying the contourlet transform for the original image, we select the low frequency directional sub band coefficients and apply singular value decomposition. The singular values of the original image are then modified by the singular va...

We propose a new method for image de-noising based on the contourlet transform, which has been recently introduced. Image de-noising by means of the contourlet transform introduces many visual artifacts due to the Gibbs-like phenomena. Due to the lack of translation invariance of the contourlet transform, we employ a cycle-spinning-based technique to develop translation invariant contourlet de-...

Steganalysis is a technique to detect the hidden embedded information in the provided data. This study proposes a novel steganalytic algorithm which distinguishes between the normal and the stego image. III level contourlet is exploited in this study. Contourlet is known for its ability to capture the intrinsic geometrical structure of an image. Here, the lowest frequency component of each leve...

To suppress the Pseudo-Gibbs phenomena caused by the Contourlet, the Nonsubsampled Pyramids Filter Banks and the Nonsubsampled Directional Filter Banks are combined to construct the nonsubsampled Contourlet transform (NSCT). Hence, The NSCT not only possess the main features of multi-scale, multi-directional and timefrequency localization, but also offer the property of the shift-invariant whic...

The aim of this paper is improving the iris segmentation with the Contourlet transform. At first iris segmentation performed by canny edge detector and Hough Transform. By this approach some images don’t segmented properly, so we want to find a way to correct the image segmentation failures. Before applying edge detector, Contourlet transform applied for image denoising. By this approach, %100 ...