An novel embedding method for image watermark based on wavelet transform is proposed. With thismethod ,the value of each pels is modified directly ,so that a bit of watermark information is embedded in every pel-s. Be...An novel embedding method for image watermark based on wavelet transform is proposed. With thismethod ,the value of each pels is modified directly ,so that a bit of watermark information is embedded in every pel-s. Before emeded ,the original image is decomposed by wavelet transform,and then,a correlation mask for every imagepels is confirmed by the characteristic and tree structure ralation of the wavelet coefficients. At last, the modified val-ue of every pels is controlled by its corresponding mask for watermark information embedded . The experimental re-suits show that the embedded digital watermarks with this proposed method are invisible and robust enough againstthe commonly used image processing techniques.展开更多
As an effective method of ownership assertion for digital media, digital watermarking has been targeted especially in recent years. In this paper, an adaptive digital watermarking embedding approach is presented. By a...As an effective method of ownership assertion for digital media, digital watermarking has been targeted especially in recent years. In this paper, an adaptive digital watermarking embedding approach is presented. By applying fuzzy c-means clustering algorithm based on human visual system, the clustering result may carry out the adaptive selection of the strength value of watermark. Compared with other means, the embedded watermark is more imperceptible and robust. In the same time, there is more anti-attack ability for embedded watermark in frequency domain than that in spatial domain. In the end, we also present results to show that our approach is applicable in practice.展开更多
This paper proposed a novel fragile watermarking scheme based on singular value decomposition (SVD) and 2D chaotic mapping. It obtains chaotic initial values from the image blocks singular value decomposition and the ...This paper proposed a novel fragile watermarking scheme based on singular value decomposition (SVD) and 2D chaotic mapping. It obtains chaotic initial values from the image blocks singular value decomposition and the user’s key, then uses the chaotic mapping to get the chaotic sequence and inserts the sequence into the LSBs of the image blocks to get the watermarked image blocks. The paper reconstructed the watermarked image from all the embedded blocks. The analysis and experimental results show that the scheme is pretty fragile to tampering, and it can localize the tampering position accurately, reach 3×3 blocks.展开更多
A novel semi-fragile audio watermarking algorithm in DWT domain is proposed in this paper.This method transforms the original audio into 3-layer wavelet domain and divides approximation wavelet coefficients into many ...A novel semi-fragile audio watermarking algorithm in DWT domain is proposed in this paper.This method transforms the original audio into 3-layer wavelet domain and divides approximation wavelet coefficients into many groups.Through computing mean quantization of per group,this algorithm embeds the watermark signal into the average value of the wavelet coefficients.Experimental results show that our semi-fragile audio watermarking algorithm is not only inaudible and robust against various common images processing,but also fragile to malicious modification.Especially,it can detect the tampered regions effectively.展开更多
Traditional watermark embedding schemes inevitably modify the data in a host audio signal and lead to the degradation of the host signal.In this paper,a novel audio zero-watermarking algorithm based on discrete wavele...Traditional watermark embedding schemes inevitably modify the data in a host audio signal and lead to the degradation of the host signal.In this paper,a novel audio zero-watermarking algorithm based on discrete wavelet transform(DWT),discrete cosine transform(DCT),and singular value decomposition(SVD) is presented.The watermark is registered by performing SVD on the coefficients generated through DWT and DCT to avoid data modification and host signal degradation.Simulation results show that the proposed zero-watermarking algorithm is strongly robust to common signal processing methods such as requantization,MP3 compression,resampling,addition of white Gaussian noise,and low-pass filtering.展开更多
A novel multiple watermarks cooperative authentication algorithm was presented for image contents authentication.This algorithm is able to extract multiple features from the image wavelet domain,which is based on that...A novel multiple watermarks cooperative authentication algorithm was presented for image contents authentication.This algorithm is able to extract multiple features from the image wavelet domain,which is based on that the t watermarks are generated.Moreover,a new watermark embedding method,using the space geometric model,was proposed,in order to effectively tackle with the mutual influences problem among t watermarks.Specifically,the incidental tampering location,the classification of intentional content tampering and the incidental modification can be achieved via mutual cooperation of the t watermarks.Both the theoretical analysis and simulations results validate the feasibility and efficacy of the proposed algorithm.展开更多
An important problem constraining the practical implementation of robust watermarking technology is the low robustness of existing algorithms against geometrical distortions. An adaptive blind watermarking scheme util...An important problem constraining the practical implementation of robust watermarking technology is the low robustness of existing algorithms against geometrical distortions. An adaptive blind watermarking scheme utilizing neural network for synchronization is proposed in this paper,which allows to recover watermark even if the image has been subjected to generalized geometrical transforms. Through classification of image’s brightness, texture and contrast sensitivity utilizing fuzzy clustering theory and human visual system, more robust watermark is adaptively embedded in DWT domain. In order to register rotation, scaling and translation parameters, feedforward neural network is utilized to learn image geometric pattern represented by six combined low order image moments. The distortion can be inverted after determining the affine distortion applied to the image and watermark can be extracted in a standard way without original image. It only needs a trained neural network. Experimental results demonstrate its advantages over previous method in terms of computational effectiveness and parameter estimation accuracy. It can embed more robust watermark under certain visual distance, and effectively resist JPEG compression, noise and geometric attacks.展开更多
In recent few years, significant improvement has been made in developing largescale 3 D printer to accommodate the need of industrial-scale 3 D printing. Cementitious materials that are compatible with 3 D printing pr...In recent few years, significant improvement has been made in developing largescale 3 D printer to accommodate the need of industrial-scale 3 D printing. Cementitious materials that are compatible with 3 D printing promote rapid application of this innovative technique in the construction field with advantages of cost effective, high efficiency, design flexibility and environmental friendly. This paper firstly reviews existing 3 D printing techniques that are currently being used in commercial3 D printers. It then summarizes three latest development of largescale 3 D printing systems and identifies their relationships and limiting factors. Thereafter, critical factors that are used to evaluate the workability and printable performance of cementitious materials are specified. Easy-extrusive, easy-flowing, well-buildable, and proper setting time are significant for cementitious material to meet the critical requirements of a freeform construction process. Finally, main advantages, potential applications and the prospects of future research of 3 D printing in construction technology are suggested. The objective of this work is to review current design methodologies and operational constraints of largescale 3 D printing system and provide references for optimizing the performance of cementitious material and promote its responsible use with largescale 3 D printing technology.展开更多
SPIE-Vol1.3959 0206641SPIE 会议录,卷3959:人类视觉与电子成象5=Pro-ceedings of SPIE,Vol.3959:Human vision and elec-tronic imaging Ⅴ[会,英]/The Society for Imaging Sci-ence and Technology & SPIE.—722P.(E)本会议录...SPIE-Vol1.3959 0206641SPIE 会议录,卷3959:人类视觉与电子成象5=Pro-ceedings of SPIE,Vol.3959:Human vision and elec-tronic imaging Ⅴ[会,英]/The Society for Imaging Sci-ence and Technology & SPIE.—722P.(E)本会议录收集了在加州 San Jose 召开的人类视觉与电子成象会议上发表的69篇论文。展开更多
文摘An novel embedding method for image watermark based on wavelet transform is proposed. With thismethod ,the value of each pels is modified directly ,so that a bit of watermark information is embedded in every pel-s. Before emeded ,the original image is decomposed by wavelet transform,and then,a correlation mask for every imagepels is confirmed by the characteristic and tree structure ralation of the wavelet coefficients. At last, the modified val-ue of every pels is controlled by its corresponding mask for watermark information embedded . The experimental re-suits show that the embedded digital watermarks with this proposed method are invisible and robust enough againstthe commonly used image processing techniques.
文摘As an effective method of ownership assertion for digital media, digital watermarking has been targeted especially in recent years. In this paper, an adaptive digital watermarking embedding approach is presented. By applying fuzzy c-means clustering algorithm based on human visual system, the clustering result may carry out the adaptive selection of the strength value of watermark. Compared with other means, the embedded watermark is more imperceptible and robust. In the same time, there is more anti-attack ability for embedded watermark in frequency domain than that in spatial domain. In the end, we also present results to show that our approach is applicable in practice.
文摘This paper proposed a novel fragile watermarking scheme based on singular value decomposition (SVD) and 2D chaotic mapping. It obtains chaotic initial values from the image blocks singular value decomposition and the user’s key, then uses the chaotic mapping to get the chaotic sequence and inserts the sequence into the LSBs of the image blocks to get the watermarked image blocks. The paper reconstructed the watermarked image from all the embedded blocks. The analysis and experimental results show that the scheme is pretty fragile to tampering, and it can localize the tampering position accurately, reach 3×3 blocks.
基金We wish to thank the National Basic Research Program of China （973 Program） for Grant 2007CB311203, the National Natural Science Foundation of China for Grant 60821001, the Specialized Research Fund for the Doctoral Program of Higher Education for Grant 20070013007 under which the present work was possible.
文摘A novel semi-fragile audio watermarking algorithm in DWT domain is proposed in this paper.This method transforms the original audio into 3-layer wavelet domain and divides approximation wavelet coefficients into many groups.Through computing mean quantization of per group,this algorithm embeds the watermark signal into the average value of the wavelet coefficients.Experimental results show that our semi-fragile audio watermarking algorithm is not only inaudible and robust against various common images processing,but also fragile to malicious modification.Especially,it can detect the tampered regions effectively.
基金supported by the Open Foundation of Jiangsu Engineering Center of Network Monitoring(Nanjing University of Information Science&Technology)(Grant No.KJR1509)the PAPD fundthe CICAEET fund
文摘Traditional watermark embedding schemes inevitably modify the data in a host audio signal and lead to the degradation of the host signal.In this paper,a novel audio zero-watermarking algorithm based on discrete wavelet transform(DWT),discrete cosine transform(DCT),and singular value decomposition(SVD) is presented.The watermark is registered by performing SVD on the coefficients generated through DWT and DCT to avoid data modification and host signal degradation.Simulation results show that the proposed zero-watermarking algorithm is strongly robust to common signal processing methods such as requantization,MP3 compression,resampling,addition of white Gaussian noise,and low-pass filtering.
基金Project(2012BAH09B02) supported by the National Science and Technology Support Program,ChinaProjects(12JJ3068,12JJ2041) supported by the Natural Science Fundation of Hunan Province,China
文摘A novel multiple watermarks cooperative authentication algorithm was presented for image contents authentication.This algorithm is able to extract multiple features from the image wavelet domain,which is based on that the t watermarks are generated.Moreover,a new watermark embedding method,using the space geometric model,was proposed,in order to effectively tackle with the mutual influences problem among t watermarks.Specifically,the incidental tampering location,the classification of intentional content tampering and the incidental modification can be achieved via mutual cooperation of the t watermarks.Both the theoretical analysis and simulations results validate the feasibility and efficacy of the proposed algorithm.
基金the National High Technology Research and Development Program of China(Grant No. 2001AA422420-02).
文摘An important problem constraining the practical implementation of robust watermarking technology is the low robustness of existing algorithms against geometrical distortions. An adaptive blind watermarking scheme utilizing neural network for synchronization is proposed in this paper,which allows to recover watermark even if the image has been subjected to generalized geometrical transforms. Through classification of image’s brightness, texture and contrast sensitivity utilizing fuzzy clustering theory and human visual system, more robust watermark is adaptively embedded in DWT domain. In order to register rotation, scaling and translation parameters, feedforward neural network is utilized to learn image geometric pattern represented by six combined low order image moments. The distortion can be inverted after determining the affine distortion applied to the image and watermark can be extracted in a standard way without original image. It only needs a trained neural network. Experimental results demonstrate its advantages over previous method in terms of computational effectiveness and parameter estimation accuracy. It can embed more robust watermark under certain visual distance, and effectively resist JPEG compression, noise and geometric attacks.
基金supported by the National Major Research Instrument Development Project of the National Natural Science Foundation of China(51627812)the opening project of State Key Laboratory of Explosion Science and Technology(Beijing Institute of Technology,KFJJ13-11M)
文摘In recent few years, significant improvement has been made in developing largescale 3 D printer to accommodate the need of industrial-scale 3 D printing. Cementitious materials that are compatible with 3 D printing promote rapid application of this innovative technique in the construction field with advantages of cost effective, high efficiency, design flexibility and environmental friendly. This paper firstly reviews existing 3 D printing techniques that are currently being used in commercial3 D printers. It then summarizes three latest development of largescale 3 D printing systems and identifies their relationships and limiting factors. Thereafter, critical factors that are used to evaluate the workability and printable performance of cementitious materials are specified. Easy-extrusive, easy-flowing, well-buildable, and proper setting time are significant for cementitious material to meet the critical requirements of a freeform construction process. Finally, main advantages, potential applications and the prospects of future research of 3 D printing in construction technology are suggested. The objective of this work is to review current design methodologies and operational constraints of largescale 3 D printing system and provide references for optimizing the performance of cementitious material and promote its responsible use with largescale 3 D printing technology.
文摘SPIE-Vol1.3959 0206641SPIE 会议录,卷3959:人类视觉与电子成象5=Pro-ceedings of SPIE,Vol.3959:Human vision and elec-tronic imaging Ⅴ[会,英]/The Society for Imaging Sci-ence and Technology & SPIE.—722P.(E)本会议录收集了在加州 San Jose 召开的人类视觉与电子成象会议上发表的69篇论文。
