A new robust reference logo watermarking scheme

In this paper, a new yet simple reference logo watermarking scheme based on fractional Fourier transform (FrFT) and singular value decomposition (SVD) is proposed. The core idea of the proposed scheme is to segment host image into non-overlapping blocks by the means of Hilbert space filling curve and a reference image is formed by considering Human visual system (HVS). First, reference image is transformed into FrFT domain and embedding is done by modifying singular values of the reference image using singular values of watermark. After embedding, modified reference image is segmented into blocks and these modified blocks are mapped into their original places for constructing watermarked image. For extraction, a reliable watermark extraction scheme is proposed. The experimental results demonstrate better visual imperceptibility and resiliency of the proposed scheme against intentional or un-intentional variety of attacks.     

A robust watermarking scheme using self-reference image

In this paper, a robust watermark scheme for copyright protection is proposed. By modifying the original image in transform domain and embedding a watermark in the difference values between the original image and its reference image, the proposed scheme overcomes the weak robustness problem of embedding a watermark in the spatial domain. Besides, the watermark extraction does not require the original image so it is more practical in real application. The experimental results show that the proposed scheme provides not only good image quality, but is also robust against various attacks, such as JPEG lossy compression, filtering and noise addition.     

Feature based robust watermarking using image normalization

This paper presents a robust watermarking scheme based on feature point detection and image normalization. Firstly some stable feature points are detected from the original image using the proposed multiresolution feature point detection filter. Then, image normalization is applied to the disks centered at these feature points. The watermark is embedded in the subband coefficients of DFT domain of each disk separately. And the watermark detection uses the correlation between the watermark embedding coefficients and the original watermark, and does not need the original image. The proposed scheme combines the advantages of feature point detection and image normalization, which can achieve strong robustness to signal processing and geometrical distortions. The experimental results also demonstrate good performance of the proposed scheme.     

A robust image watermarking algorithm using SVR detection

Geometric distortion is known as one of the most difficult attacks to resist. Geometric distortion desynchronizes the location of the watermark and hence causes incorrect watermark detection. According to the Support Vector Regression (SVR), a new image watermarking detection algorithm against geometric attacks is proposed in this paper, in which the steady Pseudo-Zernike moments and Krawtchouk moments are utilized. The host image is firstly transformed from rectangular coordinates to polar coordinates, and the Pseudo-Zernike moments of the host image are computed. Then some low-order Pseudo-Zernike moments are selected, and the digital watermark is embedded into the cover image by quantizing the magnitudes of the selected Pseudo-Zernike moments. The main steps of watermark detecting procedure include: (i) some low-order Krawtchouk moments of the image are calculated, which are taken as the eigenvectors; (ii) the geometric transformation parameters are regarded as the training objective, the appropriate kernel function is selected for training, and a SVR training model can be obtained; (iii) the Krawtchouk moments of test image are selected as input vector, the actual output (geometric transformation parameters) is predicted by using the well trained SVR, and the geometric correction is performed on the test image by using the obtained geometric transformation parameters; (iv) the digital watermark is extracted from the corrected test image. Experimental results show that the proposed watermarking detection algorithm is not only robust against common signal processing such as filtering, sharpening, noise adding, and JPEG compression etc., but also robust against the geometric attacks such as rotation, translation, scaling, cropping and combination attacks, etc.     

Novel robust image watermarking using difference correlation detector

This paper presents a robust digital image watermarking scheme based on subsampling and difference correlation. Four subimages are obtained from the host image by subsampling. A binary watermark is bit-wisely embedded in the DCT domain of two of the subimages selected by a secret key. The watermark is detected using coefficient difference correlation and does not need the original image. Since the subimages are highly correlated with each other, the proposed difference correlation detector has a better performance than a common coefficient correlation detection. Experimental results show good robustness of the proposed scheme.     

Multispectral and multiresolution image fusion using particle swarm optimization

Multispectral and multiresolution image fusion is important for many multimedia and remote sensing applications, such as video surveillance, medical imaging, and satellite imaging. For the commercial satellite ??IKONOS,?? spatial resolutions of high-resolution panchromatic (PAN) and low-resolution multispectral (MS) satellite images are 1?m and 4?m, respectively. To cope with color distortion and blocking artifacts in fused images, in this study, a multispectral and multiresolution image fusion approach using PSO is proposed. The pixels of fused images in the training set are classified into several categories based on the characteristics of low-resolution MS images. Then, the smooth parameters of spatial and spectral responses between the high-resolution PAN and low-resolution MS images are determined by PSO. All the pixels within each category are normalized by its own smooth parameter so that color distortion and blocking artifacts can be greatly reduced. Based on the experimental results obtained in this study, the overall visual quality of the fused images by the proposed approach is better than that by three comparison approaches, whereas the correlation coefficients, ?? _PAN , for the fused images by the proposed approach are greater than that by three comparison approaches.     

A robust logo watermarking technique in divisive normalization transform domain

In this paper, a novel image watermarking scheme has been presented, which is based on Divisive Normalization Transform, Discrete Wavelet Transform and Singular Value Decomposition. Through this paper an attempt has been made to solve the problem of statically and perceptually redundant wavelet coefficients, used during watermarking with the help of divisive normalization transform while maintaining the robustness and imperceptibility. Divisive Normalization Transform is an adaptive nonlinear image illustration in which all linear transform coefficient are divided by a weighted sum of coefficient amplitudes in a generalized neighbourhood. The idea of embedding the watermark image into singular values of divisively normalized coefficients of host image has been exploited. The proposed algorithm is providing the perceptually better-quality watermarked image and at the same time maintaining the robustness of watermarked algorithm. Thus the proposed watermarking algorithm is a semi-blind, image adaptive due to use of divisive normalization transform and suitable for rightful ownership. Various comparative results make the algorithm superior in terms of intentional and non-intentional attacks.     

一种基于小波变换的多分辨图像融合算法

图像的融合过程是将两个或更多的图像结合成一个图像,融合图像保留了每一个图像的重要特征。图像融合技术能够提高图像质量和数据的实用性。主要描述了图像融合的两个课题：（1）融合算法;（2）质量评估。介绍的图像融合算法是先对原图像进行多分辨小波变换,再把输入图像的小波变换系数通过一定的融合规则进行选择,然后经过逆小波变换得到新的图像,对图像融合的质量评估也进行了讨论。     

A robust content based image watermarking using local invariant histogram

Desynchronization attack is known as one of the most difficult attacks to resist, which can desynchronize the location of the watermark and hence causes incorrect watermark detection. Based on multi-scale SIFT (Scale Invariant Feature Transform) detector and local image histogram shape invariance, we propose a new content based image watermarking algorithm with good visual quality and reasonable resistance toward desynchronization attacks in this paper. Firstly, the stable image feature points are extracted from the original host by using multi-scale SIFT detector, and the local feature regions (LFRs) are constructed adaptively according to the feature scale theory. Then, the discrete Fourier transform (DFT) is performed on the LFR, and the local image histogram is extracted from a selected DFT amplitude range. Finally, the bins of the histogram are divided into many groups, and the digital watermark is embedded into LFR by reassigning the number of DFT amplitudes in bin groups. By binding the watermark with the geometrically invariant image features, the watermark detection can be done without synchronization error. Experimental results show that the proposed image watermarking is not only invisible and robust against common image processing operations such as sharpening, noise adding, and JPEG compression, but also robust against the desynchronization attacks such as rotation, translation, scaling, row or column removal, and cropping.     

A secure and robust color image watermarking using nature-inspired intelligence

Neural Computing and Applications - The security of multimedia information is a prime concern in the present digital world. As a remedy, a robust color image watermarking in the transform domain...     

Robust logo watermarking using biometrics inspired key generation

In this paper, a novel logo watermarking technique with key concept is proposed using fractional wavelet packet transform (FrWPT), non-linear chaotic map and singular value decomposition (SVD). The core idea is to use biometrically generated keys in the embedding process of gray-scale watermark. Therefore, this paper first proposes a method for generating keys from biometrics efficiently. Then the host image is first randomized with the help of non-linear chaotic map followed by the embedding in the FrWPT domain by modifying the singular values of the randomized image. Further, in order to enhance the security, an authentication key is formed to authenticate the watermarked image. Finally, a reliable extraction process is proposed to extracted watermark from the possibly attacked authenticate watermarked image. The security, attack and comparative analysis confirm high security, efficiency and robustness of the proposed watermarking technique. Further, an efficient solution is also proposed to deal with the ambiguous situations created by SVD in watermarking.     

Synchronization correction-based robust digital image watermarking approach using Bessel K-form PDF

Pattern Analysis and Applications - Robustness has played extremely important role in the multiple applications of digital watermarking technology. The reason lies in its influence on the...     

多分辨率图像融合的研究与发展

本文系统综述了多分辨率图像融合算法的发展历程和理论研究.首先论述了多分辨率图像融合算法的基本原理及发展状况;然后给出了多分辨率图像融合中的几种典型算法,并做了较详细的分析与讨论;最后对多分辨率图像融合存在的问题及其发展做了探讨.     

A robust color image watermarking using local invariant significant bitplane histogram

Desynchronization attacks that cause displacement between embedding and detection are usually difficult for watermark to survive. It is a challenging work to design a robust image watermarking scheme against desynchronization attacks, especially for color images. In this paper, we propose a robust color image watermarking approach based on local invariant significant bitplane histogram. The novelty of the proposed approach includes: 1) A fast and effective color image feature points detector is constructed, in which probability density and color invariance model are used; 2) The fully affine invariant local feature regions are built based on probability density Hessian matrix; and 3) The invariant significant bitplane histograms are introduced to embed digital watermark. The extensive experimental works are carried out on a color image set collected from Internet, and the preliminary results show that the proposed watermarking approach can survive numerous kinds of distortions, including common image processing operations and desynchronization attacks.     

Partially compressed-encrypted domain robust JPEG image watermarking

Digital media is often handled in a compressed and encrypted form in Digital Asset Management Systems. And watermarking of the compressed encrypted media items in the compressed-encrypted domain itself is required sometimes for copyright violation detection or other purposes. In this paper, we propose a robust image watermarking technique for partially compressed-encrypted JPEG images. However, arbitrary embedding of a watermark in a partially compressed encrypted image can cause drastic degradation of the quality as the underlying change may result in random decrypted values. In addition, due to the encryption the compression efficiency may become very low. Thus the challenge is to design a watermarking technique that provides good watermarked image quality and at the same time gives good compression efficiency. While the proposed technique embeds watermark in the partially compressed-encrypted domain, the extraction of watermark can be done in the encrypted or decrypted domains. The experiments show that the watermarked image quality is good and the reduction in compression efficiency is low. The proposed watermarking technique is robust to common signal processing attacks. The watermark detection performance of the proposed scheme is better than the existing encrypted domain watermarking techniques.     

Toward a new wavelet-based watermarking approach for color images using bio-inspired optimization principles

This paper presents a novel watermarking approach for copyright protection of color images based on the wavelet transformation. We consider the problem of logo watermarking and employ the genetic algorithm optimization principles to obtain performance improvement with respect to the existing algorithms. In the proposed method, the strength of the embedded watermark is controlled locally and according to the visual properties of the host signal. These parameters are varied to find the most suitable ones for images with different characteristics. The experimental results show that the proposed algorithm yields a watermark which is invisible to human eyes and robust to a wide variety of common attacks.     

A robust image watermarking scheme using Arnold transform and BP neural network

Neural Computing and Applications - The protection and authentication of multimedia contents and copyright have become a great concern in the fast-growing Internet environment. This paper presents...     

2DOTS-multi-bit-encoding for robust and imperceptible image watermarking

Multimedia Tools and Applications - In this article, a new and improvised image watermarking (IW) technique on colored images is proposed to mitigate robustness and imperceptibility issues found...     

Circularly orthogonal moments for geometrically robust image watermarking

Circularly orthogonal moments, such as Zernike moments (ZMs) and pseudo-Zernike moments (PZMs), have attracted attention due to their invariance properties. However, we find that for digital images, the invariance properties of some ZMs/PZMs are not perfectly valid. This is significant for applications of ZMs/PZMs. By distinguishing between the ‘good’ and ‘bad’ ZMs/PZMs in terms of their invariance properties, we design image watermarks with ‘good’ ZMs/PZMs to achieve watermark's robustness to geometric distortions, which has been considered a crucial and difficult issue in the research of digital watermarking. Simulation results show that the embedded information can be decoded at low error rates, robust against image rotation, scaling, flipping, as well as a variety of other common manipulations such as lossy compression, additive noise and lowpass filtering.     

An IWT based blind and robust image watermarking scheme using secret key matrix

Multimedia Tools and Applications - In this paper, the authors have proposed a binary watermark embedding approach for protecting the copyright ownership of the gray-scale images. The proposed...