Since interference noise and limited imaging algorithm etc caused low-quality images, continuous contour information on targets was difficult to extract, and ISAR imaging on aerial targets wasn’t ideal. On this basis, a new method of image processing is proposed to achieve clearer continuous contour features on targets. The method combines denoising technique based on Contourlet transform with ...

This paper presents a contourlet transform based watermarking scheme for colour images. It also makes use of discrete cosine transform and singular value decomposition. Discrete cosine transform is applied on three colour components (Y, Cb and Cr), obtained from the colour image, to produce DCT coefficients. These coefficients are decomposed into directional subbands using 2level contourlet tra...

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...

In all methods of image denoising there is a problem always exists that is how to distinguish noise and edge. Now wavelet and contourlet are main tools in image denoising, but threshold is the key in wavelet and contourlet denoising. In order to distinguish noise and edge well, most methods in wavelet denoising are about the improvement of threshold. Aiming to resolve this problem, a new method...

This work presents adaptive image steganography methods which locate suitable regions for embedding by contourlet transform, while embedded message bits are carried in discrete cosine transform coefficients. The first proposed method utilizes contourlet transform coefficients to select contour regions of the image. In the embedding procedure, some of the contourlet transform coefficients may ch...

one of the challenging issues in managing the existing large digital image libraries and databases is content based image retrieval (cbir). the accuracy of image retrieval methods in cbir is subject to effective extraction of image features such as color, texture, and shape. in this paper, we propose a new image retrieval method using contourlet transform coefficients to index texture of the im...

Contourlet transform is an effective solution to solve two or more dimensional singularity and has good direction and anisotropy. Against the shortage of ability of describing the spatial distribution characteristic of object’s edge information, this paper proposed a new image retrieval algorithm based on Contourlet transform, which blocks the indexed image and decomposes each sub-block images ...

This paper presents a new blind approach of image Steganalysis based on contourlet transform and non linear support vector machine. Properties of Contourlet transform are used to extract features of images, and non linear support vector machine is used to classify the stego and cover images. The important aspect of this paper is that, it uses the minimum number of features in the transform doma...

This paper presents an oblivious watermarking scheme based on contourlet transform and quantization index modulus modulation (QIMM).The scheme has the following features. First, the proposed scheme makes better use of multidirectional characteristic of contourlet transform and embed the watermark into the 4 directional high pass sub bands. Second, the scheme avoids the problem of selection of w...

A new multifocus image fusion approach is presented in this paper. First the contourlet transform is used to decompose the source images into different components. Then, some salient features are extracted from components. In order to extract salient features, spatial frequency is used. Subsequently, the best coefficients from the components are selected by the maximum selection rule. Finally, ...