Palmprint recognition is an accepted and widely used biometric. Richness of feature and the less cost involved in acquisition make it more reliable and user friendly. The region of interest is extracted from the palmprint image as a preprocessing step. Contourlet transform, a pyramidal directional filter bank is then applied to capture both local and global details of the palmprint. The large n...

Contourlet transform has been proved superior to wavelet in representation piecewise texture and contour characters in digital images. In order to improve the retrieval rate further, we studied the representation abilities of some different filters for texture features in two contourlet retrieval systems. The two systems both used Canberra distance for similarity measure, but different feature ...

Designing a reliable and generic perceptual quality metric is a challenging issue in three-dimensional (3D) visual signal processing. In many practical 3D application scenarios, the original stereoscopic images (i.e., the reference image) cannot be fully accessed, leaving difficulties to quality assessment. To handle this problem, 3D reduced-reference image quality assessment (RRIQA) metrics ha...

In this paper, a new multi-resolution tool, namely contourlet transform, is used to extract features for face recognition, which efficiently exploits the local spatial variations in a face image. Multi-resolution ideas, notably the wavelet transform, have been profusely employed for addressing the problem of face recognition. However, theoretical studies indicate that digital contourlet transfo...

In this paper, a new bivariate shrinkage denoising method is proposed to model statistics of shearlet coefficients of images. Using Bayesian estimation theory we derive from this model a simple non-linear shrinkage function for shearlet denoising, which generalizes the soft threshold approach. Experimental results show that the proposed method can remove Gaussian white noise while effectively p...

Speckle noise affects all coherent imaging systems including medical ultrasound. In medical images, noise suppression is a particularly delicate and difficult task. A tradeoff between noise reduction and the preservation of actual image features has to be made in a way that enhances the diagnostically relevant image content. Even though wavelets have been extensively used for denoising speckle ...

The limitations of commonly used separable extensions of one-dimensional transforms, such as the Fourier and wavelet transforms, in capturing the geometry of image edges are well known.A ―true‖ two dimensional transform that can capture the intrinsic geometrical structure that is key in visual information. The main challenge in exploring geometry in images comes from the discrete nature of the ...

Image fusion is the process of combining relevant information from two or more images into a single fused image. The resulting image will be more informative than any of the input images. The fusion in medical images is necessary for efficient diseases diagnosis from multimodality, multidimensional and multi parameter type of images. This paper describes a multimodality medical image fusion sys...

Recently, the contourlet transform has been developed as a true two-dimensional representation that can capture the geometrical structure in pictorial information. Unlike other transforms that were initially constructed in the continuous-domain and then discretized for sampled data, the contourlet construction starts from the discrete-domain using filter banks, and then convergences to a contin...