The paper analyzed a new watermarking detection paradigm including double detection thresholds based on sequential hypothesis testing. A joint design of watermarking encoding and detection was proposed. The paradigm h...The paper analyzed a new watermarking detection paradigm including double detection thresholds based on sequential hypothesis testing. A joint design of watermarking encoding and detection was proposed. The paradigm had good immunity to noisy signal attacks and high detection probability. Many experiments proved that the above algorithm can detect watermarks about 66% faster than popular detectors, which could have significant impact on many applications such as video watermarking detection and watermark-searching in a large database of digital contents.展开更多
针对在原始图像中嵌入大量的水印(认证水印和参考水印)容易造成图像失真的问题,提出嵌入少量参考水印的方法。为了减小图像失真,提出将少量的参考水印信息嵌入在原始图像的边缘、轮廓等区域的方法。在恢复篡改区域时,提出利用图像修复...针对在原始图像中嵌入大量的水印(认证水印和参考水印)容易造成图像失真的问题,提出嵌入少量参考水印的方法。为了减小图像失真,提出将少量的参考水印信息嵌入在原始图像的边缘、轮廓等区域的方法。在恢复篡改区域时,提出利用图像修复算法将篡改块匹配问题转化为非局部自相似图像块的最小化问题,复制攻击图像本身的相似信息来恢复篡改区域。实验结果表明,在水印容量为0.015626的情况下,该算法得到嵌入水印后图像的峰值信噪比(peak signal to noise ratio,PSNR)均值超过60 dB,恢复图像的PSNR均值超过40 dB。展开更多
Technology has no limits today;we have lots of software available in the market by which we can alter any image. People usually copies image from the internet and after some changes they claim that these are their own...Technology has no limits today;we have lots of software available in the market by which we can alter any image. People usually copies image from the internet and after some changes they claim that these are their own properties. Insuring digital image integrity has therefore become a major issue. Over the past few years, watermarking has emerged as the leading candidate to solve problems of ownership and content authentications for digital multimedia documents. To protect authenticity of images semi fragile watermarking is very concerned by researchers because of its important function in multimedia content authentication. The aim of this paper is to present a survey and a comparison of emerging techniques for image authentication using semifragile watermarking. In present paper comprehensive overview of insertion and extraction methods used in different semi fragile water marking algorithm are studied using image parameters, potential application, different algorithms are described and focus is on their comparison according to the properties cited above and future directions for developing a better image authentication algorithm are suggested.展开更多
Many common multimedia signal processing, including cropping, filtering, and perceptual coding, make watermark signal fading-like modification. A scheme that applies transmit diversity technique to improve robustness ...Many common multimedia signal processing, including cropping, filtering, and perceptual coding, make watermark signal fading-like modification. A scheme that applies transmit diversity technique to improve robustness of digital watermarking is presented. First, the scheme decomposes the original image using wavelet pyramid algorithm and chooses the middle-frequency band for transmission channel that the watermark will be embedded into. Then the watermark is pseudo-randomly permuted. The scheme makes use of space-time coding and differential detection technique to embed and extract watermark. The extracting process has access to neither the original image nor channel state information. Experimental results demonstrate that the scheme improves the performance of robust watermarking.展开更多
A recent trend of the digital watermark requires not only the robustness but also speed. To achieve these requirements, we propose a watermark synchronization scheme based on two kinds of templates. The first one is t...A recent trend of the digital watermark requires not only the robustness but also speed. To achieve these requirements, we propose a watermark synchronization scheme based on two kinds of templates. The first one is the rotation invariant template for estimating scale parameter, and the second is the scale invariant template for estimating rotation parameter. Theoretically, complementary templates greatly reduce the search space at the detection stage and achieve robustness against the RST distortion. The results report that the proposed method is useful for the water- mark detection system which requires both a real-time detection and robustness.展开更多
A new robust watermarking approach was proposed in 2D continuous wavelet domain （CWT）. The watermark is embedded into the large coefficients in the middle band of wavelet transform modulus maxima （WTMM） of the hos...A new robust watermarking approach was proposed in 2D continuous wavelet domain （CWT）. The watermark is embedded into the large coefficients in the middle band of wavelet transform modulus maxima （WTMM） of the host image. After possible attacks, the watermark is then detected and extracted by correlation analysis. Compared with other wavelet domain watermarking approaches, the WTMM approach can endow the image with beth rotation and shift invariant properties. On the other hand, scale invariance is achieved with the geometric normalization during watermark detection. Case studies involve various attacks such as shifting, lossy compression, scaling, rotation and median filtering on the watermarked image, and the result shows that the approach is robust to these attacks.展开更多
为维护广播内容的完整性与合法性,研究广播电视信号检测中的水印嵌入与提取技术。介绍数字水印的概念,探讨在广播电视信号中嵌入水印的过程,特别是加速稳健特征(Speeded Up Robust Features,SURF)算法的应用,阐述水印提取与检测方法,以...为维护广播内容的完整性与合法性,研究广播电视信号检测中的水印嵌入与提取技术。介绍数字水印的概念,探讨在广播电视信号中嵌入水印的过程,特别是加速稳健特征(Speeded Up Robust Features,SURF)算法的应用,阐述水印提取与检测方法,以确保广播内容的完整性。通过功能分析,展示该技术在广播电视行业中对未经授权的广告插播检测和信号篡改检测的关键作用。展开更多
基金This is work is supported by Shanghai Municipal Education Commission (NO.04DC33, NO. 2000SG46)
文摘The paper analyzed a new watermarking detection paradigm including double detection thresholds based on sequential hypothesis testing. A joint design of watermarking encoding and detection was proposed. The paradigm had good immunity to noisy signal attacks and high detection probability. Many experiments proved that the above algorithm can detect watermarks about 66% faster than popular detectors, which could have significant impact on many applications such as video watermarking detection and watermark-searching in a large database of digital contents.
文摘针对在原始图像中嵌入大量的水印(认证水印和参考水印)容易造成图像失真的问题,提出嵌入少量参考水印的方法。为了减小图像失真,提出将少量的参考水印信息嵌入在原始图像的边缘、轮廓等区域的方法。在恢复篡改区域时,提出利用图像修复算法将篡改块匹配问题转化为非局部自相似图像块的最小化问题,复制攻击图像本身的相似信息来恢复篡改区域。实验结果表明,在水印容量为0.015626的情况下,该算法得到嵌入水印后图像的峰值信噪比(peak signal to noise ratio,PSNR)均值超过60 dB,恢复图像的PSNR均值超过40 dB。
文摘Technology has no limits today;we have lots of software available in the market by which we can alter any image. People usually copies image from the internet and after some changes they claim that these are their own properties. Insuring digital image integrity has therefore become a major issue. Over the past few years, watermarking has emerged as the leading candidate to solve problems of ownership and content authentications for digital multimedia documents. To protect authenticity of images semi fragile watermarking is very concerned by researchers because of its important function in multimedia content authentication. The aim of this paper is to present a survey and a comparison of emerging techniques for image authentication using semifragile watermarking. In present paper comprehensive overview of insertion and extraction methods used in different semi fragile water marking algorithm are studied using image parameters, potential application, different algorithms are described and focus is on their comparison according to the properties cited above and future directions for developing a better image authentication algorithm are suggested.
基金This project was supported by the National Natural Science Foundation of China(60072041).
文摘Many common multimedia signal processing, including cropping, filtering, and perceptual coding, make watermark signal fading-like modification. A scheme that applies transmit diversity technique to improve robustness of digital watermarking is presented. First, the scheme decomposes the original image using wavelet pyramid algorithm and chooses the middle-frequency band for transmission channel that the watermark will be embedded into. Then the watermark is pseudo-randomly permuted. The scheme makes use of space-time coding and differential detection technique to embed and extract watermark. The extracting process has access to neither the original image nor channel state information. Experimental results demonstrate that the scheme improves the performance of robust watermarking.
文摘A recent trend of the digital watermark requires not only the robustness but also speed. To achieve these requirements, we propose a watermark synchronization scheme based on two kinds of templates. The first one is the rotation invariant template for estimating scale parameter, and the second is the scale invariant template for estimating rotation parameter. Theoretically, complementary templates greatly reduce the search space at the detection stage and achieve robustness against the RST distortion. The results report that the proposed method is useful for the water- mark detection system which requires both a real-time detection and robustness.
基金The National Natural Science Foundation of China (No.60703048)the Natural Science Foundation of Hubei Province (No.2007ABA303)
文摘A new robust watermarking approach was proposed in 2D continuous wavelet domain （CWT）. The watermark is embedded into the large coefficients in the middle band of wavelet transform modulus maxima （WTMM） of the host image. After possible attacks, the watermark is then detected and extracted by correlation analysis. Compared with other wavelet domain watermarking approaches, the WTMM approach can endow the image with beth rotation and shift invariant properties. On the other hand, scale invariance is achieved with the geometric normalization during watermark detection. Case studies involve various attacks such as shifting, lossy compression, scaling, rotation and median filtering on the watermarked image, and the result shows that the approach is robust to these attacks.
文摘为维护广播内容的完整性与合法性,研究广播电视信号检测中的水印嵌入与提取技术。介绍数字水印的概念,探讨在广播电视信号中嵌入水印的过程,特别是加速稳健特征(Speeded Up Robust Features,SURF)算法的应用,阐述水印提取与检测方法,以确保广播内容的完整性。通过功能分析,展示该技术在广播电视行业中对未经授权的广告插播检测和信号篡改检测的关键作用。
