3D cameras are capable of capturing image and depth map of an object simultaneously. We propose a... more 3D cameras are capable of capturing image and depth map of an object simultaneously. We propose a method to hide depth map, as a watermark, in its corresponding 2D image. 3D cameras enabled with this functionality could serve two purposes; protection of the captured image and secure transmission of its depth map.
This paper presents a lossless data hiding approach based on integer wavelet transform and variab... more This paper presents a lossless data hiding approach based on integer wavelet transform and variable threshold for a novel application of watermarking. In this novel application, a depth map of an object obtained from sequence of 2D images is secretly embedded in one of the 2-D images for subsequent 3-D analysis after transmission. Additionally, for efficient generation of the depth map, we also propose a new focus measure based on discrete cosine transform (DCT) and principal component analysis. The proposed approach is able not only in extracting the depth map, but also recovers the cover image. Experimental results show the capability of the proposed approach of secretly transmitting and retrieving the depth information. The employment of this novel idea of hiding depth maps in corresponding 2-D cover images could be helpful in medical and military image processing, security based stickers, mobile advertizing, image vision, law enforcement, etc. Additionally, if the depth map is generated through a standard approach, it could also help in the authentication related applications of the cover image.
This paper presents a novel approach of adaptive visual tuning of a watermark in Discrete Cosine ... more This paper presents a novel approach of adaptive visual tuning of a watermark in Discrete Cosine Transform (DCT) domain. The proposed approach intelligently selects appropriate frequency bands as well as optimal strength of alteration. Genetic Programming (GP) is applied to structure the watermark by exploiting both the characteristics of human visual system and information pertaining to a cascade of conceivable attacks. The developed visual tuning expressions are dependent on frequency and luminance sensitivities, and contrast masking. To further enhance robustness, spread spectrum based watermarking and Bose-Chadhuri-Hocquenghem (BCH) coding is employed. The combination of spread spectrum sequence, BCH coding and GP based non-linear structuring makes it extremely difficult for an attacker to gain information about the secret knowledge of the watermarking system. Experimental results show the superiority of the proposed approach against the existing approaches. Especially, the margin of improvement in robustness will be of high importance in medical and context aware related applications of watermarking. ß
This paper presents a semi-fragile watermarking technique capable of verifying the authenticity a... more This paper presents a semi-fragile watermarking technique capable of verifying the authenticity and recovery of the image. The proposed approach has the capability to accurately detect and differentiate modifications applied on the watermarked image. Alteration sensitivity has been improved compared to previous approaches and it can concisely determine the region of the watermarked image where the integrity verification fails. Semi-fragility makes the proposed method tolerant against JPEG lossy compression and other acceptable modifications but sensitive to malicious attacks such as cutting and pasting. The exact low pass version of the image is recovered by using the lossless compression (Huffman coding). Simulation results demonstrate that the alteration sensitivity of the proposed authentication scheme is much better compared to the previous approaches.
This paper presents a semi-fragile watermarking technique capable of both authenticating and reco... more This paper presents a semi-fragile watermarking technique capable of both authenticating and recovering an image. The proposed approach offers choice of embedding two watermarks and is able to detect and differentiate the modifications applied on the watermarked image. Semi-fragility makes the scheme tolerant against JPEG lossy compression. While, recovery attribute makes it suitable for video surveillance and remote sensing applications.
In this work, we present a generalized scheme for embedding watermark in digital images used for ... more In this work, we present a generalized scheme for embedding watermark in digital images used for commercial aims. Genetic Programming is used to develop appropriate visual tuning functions, in accordance with Human Visual System, which cater for watermark imperceptibility-robustness trade off in the presence of a series of probable attacks. The use of low-density parity check codes for information encoding further enhances watermark robustness. Experimental results on a dataset of test images show marked improvement in robustness, when compared to the conventional approaches with the same level of visual quality. The proposed scheme is easy to implement and ensures significant robustness for watermarking a large number of small digital images.
Aeu-international Journal of Electronics and Communications, 2011
This letter presents a novel approach of incorporating intelligence in the encoding and decoding ... more This letter presents a novel approach of incorporating intelligence in the encoding and decoding structures of a watermarking system. The employment of computational intelligence makes the watermarking system resistant against a series of attacks, which may occur during the storage or communication of the watermarked work. Keeping in view the Human Visual System, Genetic Programming is used to generate functions which select optimum strength and location of transform domain coefficients for watermark embedding. Support Vector Machines and Artificial Neural Networks are employed at the decoding side to learn about the distortions due to attacks and counteract them. Especially, the proposed system is quite effective for robust watermarking applications of small size images such as those displayed on portable devices and online catalogs.
Information hiding for authenticating and verifying the content integrity of the multimedia has b... more Information hiding for authenticating and verifying the content integrity of the multimedia has been exploited extensively in the last decade. We propose the idea of using genetic algorithm and non-deterministic dependence by involving the unwatermarkable coefficients for digital image authentication. Genetic algorithm is used to intelligently select coefficients for watermarking in a DCT based image authentication scheme, which implicitly watermark all the un-watermarkable coefficients also, in order to thwart different attacks. Experimental results show that such intelligent selection results in improvement of imperceptibility of the watermarked image, and implicit watermarking of all the coefficients improves security against attacks such as cover-up, vector quantization and transplantation.
A novel wavelet domain based semi-fragile watermarking scheme is presented for securing digital c... more A novel wavelet domain based semi-fragile watermarking scheme is presented for securing digital content and to concisely determine the regions where the integrity fails. In addition, another watermark is embedded to perform self-recovery in case of malicious attack. The security weaknesses of the traditional block-based approaches are circumvented by correlating the watermark bits with wavelet coefficients of the approximation subband of the host image. Semi-fragility exhibits robustness to JPEG compression, while recovery attribute makes the scheme suitable for video surveillance and remote sensing applications. Experimental investigations are performed to evaluate the performance of the proposed multiple semi-fragile watermarks and shows the suitability of the proposed approach for accurate authentication and recovery based applications.
Robustness and imperceptibility are two essential but contradicting properties in robust digital ... more Robustness and imperceptibility are two essential but contradicting properties in robust digital watermarking. This paper proposes an approach for obtaining superior robustness-imperceptibility tradeoff by considering the likely set of attacks a watermark is expected to be mounted with. The suggested approach achieves this improvement by using Genetic Programming to develop appropriate perceptual shaping functions for structuring the watermark intelligently by choosing the optimum strength of allowable alteration in watermarkable DCT features, in view of a set of conceivable attacks. The developed perceptual shaping functions, which outperform the conventional ones, are generalized with respect to the cover work and are based on the watermark application.
Reversible data hiding technique enables the exact recovery of original contents upon extraction ... more Reversible data hiding technique enables the exact recovery of original contents upon extraction of embedding data. Many conventional watermarking algorithms that have been proposed so far, suffer from the problem of low embedding capacity. In many applications huge amount of data is required to embed and exact recovery of host image is also needed. Luo's additive interpolation-error expansion technique [1] is a high capacity reversible method for data embedding without zero loss of host information. In this paper, we focus on improving payload and imperceptibility, and we propose an algorithm which is an extension of interpolationerror scheme using Particle Swarm Optimization (PSO) which better exploits estimation of missing pixel. The experimental results demonstrate that due to slight modification in interpolation-error technique, we achieve large hiding capacity and improved image quality compared with other schemes.
Reversible data hiding technique enables the exact recovery of original contents upon extraction ... more Reversible data hiding technique enables the exact recovery of original contents upon extraction of embedding data. Many conventional watermarking algorithms that have been proposed so far, suffer from the problem of low embedding capacity. In many applications huge amount of data is required to embed and exact recovery of host image is also needed. Luo's additive interpolation-error expansion technique [1] is a high capacity reversible method for data embedding without zero loss of host information. In this paper, we focus on improving payload and imperceptibility, and we propose an algorithm which is an extension of interpolationerror scheme using Particle Swarm Optimization (PSO) which better exploits estimation of missing pixel. The experimental results demonstrate that due to slight modification in interpolation-error technique, we achieve large hiding capacity and improved image quality compared with other schemes.
3D cameras are capable of capturing image and depth map of an object simultaneously. We propose a... more 3D cameras are capable of capturing image and depth map of an object simultaneously. We propose a method to hide depth map, as a watermark, in its corresponding 2D image. 3D cameras enabled with this functionality could serve two purposes; protection of the captured image and secure transmission of its depth map.
This paper presents a lossless data hiding approach based on integer wavelet transform and variab... more This paper presents a lossless data hiding approach based on integer wavelet transform and variable threshold for a novel application of watermarking. In this novel application, a depth map of an object obtained from sequence of 2D images is secretly embedded in one of the 2-D images for subsequent 3-D analysis after transmission. Additionally, for efficient generation of the depth map, we also propose a new focus measure based on discrete cosine transform (DCT) and principal component analysis. The proposed approach is able not only in extracting the depth map, but also recovers the cover image. Experimental results show the capability of the proposed approach of secretly transmitting and retrieving the depth information. The employment of this novel idea of hiding depth maps in corresponding 2-D cover images could be helpful in medical and military image processing, security based stickers, mobile advertizing, image vision, law enforcement, etc. Additionally, if the depth map is generated through a standard approach, it could also help in the authentication related applications of the cover image.
This paper presents a novel approach of adaptive visual tuning of a watermark in Discrete Cosine ... more This paper presents a novel approach of adaptive visual tuning of a watermark in Discrete Cosine Transform (DCT) domain. The proposed approach intelligently selects appropriate frequency bands as well as optimal strength of alteration. Genetic Programming (GP) is applied to structure the watermark by exploiting both the characteristics of human visual system and information pertaining to a cascade of conceivable attacks. The developed visual tuning expressions are dependent on frequency and luminance sensitivities, and contrast masking. To further enhance robustness, spread spectrum based watermarking and Bose-Chadhuri-Hocquenghem (BCH) coding is employed. The combination of spread spectrum sequence, BCH coding and GP based non-linear structuring makes it extremely difficult for an attacker to gain information about the secret knowledge of the watermarking system. Experimental results show the superiority of the proposed approach against the existing approaches. Especially, the margin of improvement in robustness will be of high importance in medical and context aware related applications of watermarking. ß
This paper presents a semi-fragile watermarking technique capable of verifying the authenticity a... more This paper presents a semi-fragile watermarking technique capable of verifying the authenticity and recovery of the image. The proposed approach has the capability to accurately detect and differentiate modifications applied on the watermarked image. Alteration sensitivity has been improved compared to previous approaches and it can concisely determine the region of the watermarked image where the integrity verification fails. Semi-fragility makes the proposed method tolerant against JPEG lossy compression and other acceptable modifications but sensitive to malicious attacks such as cutting and pasting. The exact low pass version of the image is recovered by using the lossless compression (Huffman coding). Simulation results demonstrate that the alteration sensitivity of the proposed authentication scheme is much better compared to the previous approaches.
This paper presents a semi-fragile watermarking technique capable of both authenticating and reco... more This paper presents a semi-fragile watermarking technique capable of both authenticating and recovering an image. The proposed approach offers choice of embedding two watermarks and is able to detect and differentiate the modifications applied on the watermarked image. Semi-fragility makes the scheme tolerant against JPEG lossy compression. While, recovery attribute makes it suitable for video surveillance and remote sensing applications.
In this work, we present a generalized scheme for embedding watermark in digital images used for ... more In this work, we present a generalized scheme for embedding watermark in digital images used for commercial aims. Genetic Programming is used to develop appropriate visual tuning functions, in accordance with Human Visual System, which cater for watermark imperceptibility-robustness trade off in the presence of a series of probable attacks. The use of low-density parity check codes for information encoding further enhances watermark robustness. Experimental results on a dataset of test images show marked improvement in robustness, when compared to the conventional approaches with the same level of visual quality. The proposed scheme is easy to implement and ensures significant robustness for watermarking a large number of small digital images.
Aeu-international Journal of Electronics and Communications, 2011
This letter presents a novel approach of incorporating intelligence in the encoding and decoding ... more This letter presents a novel approach of incorporating intelligence in the encoding and decoding structures of a watermarking system. The employment of computational intelligence makes the watermarking system resistant against a series of attacks, which may occur during the storage or communication of the watermarked work. Keeping in view the Human Visual System, Genetic Programming is used to generate functions which select optimum strength and location of transform domain coefficients for watermark embedding. Support Vector Machines and Artificial Neural Networks are employed at the decoding side to learn about the distortions due to attacks and counteract them. Especially, the proposed system is quite effective for robust watermarking applications of small size images such as those displayed on portable devices and online catalogs.
Information hiding for authenticating and verifying the content integrity of the multimedia has b... more Information hiding for authenticating and verifying the content integrity of the multimedia has been exploited extensively in the last decade. We propose the idea of using genetic algorithm and non-deterministic dependence by involving the unwatermarkable coefficients for digital image authentication. Genetic algorithm is used to intelligently select coefficients for watermarking in a DCT based image authentication scheme, which implicitly watermark all the un-watermarkable coefficients also, in order to thwart different attacks. Experimental results show that such intelligent selection results in improvement of imperceptibility of the watermarked image, and implicit watermarking of all the coefficients improves security against attacks such as cover-up, vector quantization and transplantation.
A novel wavelet domain based semi-fragile watermarking scheme is presented for securing digital c... more A novel wavelet domain based semi-fragile watermarking scheme is presented for securing digital content and to concisely determine the regions where the integrity fails. In addition, another watermark is embedded to perform self-recovery in case of malicious attack. The security weaknesses of the traditional block-based approaches are circumvented by correlating the watermark bits with wavelet coefficients of the approximation subband of the host image. Semi-fragility exhibits robustness to JPEG compression, while recovery attribute makes the scheme suitable for video surveillance and remote sensing applications. Experimental investigations are performed to evaluate the performance of the proposed multiple semi-fragile watermarks and shows the suitability of the proposed approach for accurate authentication and recovery based applications.
Robustness and imperceptibility are two essential but contradicting properties in robust digital ... more Robustness and imperceptibility are two essential but contradicting properties in robust digital watermarking. This paper proposes an approach for obtaining superior robustness-imperceptibility tradeoff by considering the likely set of attacks a watermark is expected to be mounted with. The suggested approach achieves this improvement by using Genetic Programming to develop appropriate perceptual shaping functions for structuring the watermark intelligently by choosing the optimum strength of allowable alteration in watermarkable DCT features, in view of a set of conceivable attacks. The developed perceptual shaping functions, which outperform the conventional ones, are generalized with respect to the cover work and are based on the watermark application.
Reversible data hiding technique enables the exact recovery of original contents upon extraction ... more Reversible data hiding technique enables the exact recovery of original contents upon extraction of embedding data. Many conventional watermarking algorithms that have been proposed so far, suffer from the problem of low embedding capacity. In many applications huge amount of data is required to embed and exact recovery of host image is also needed. Luo's additive interpolation-error expansion technique [1] is a high capacity reversible method for data embedding without zero loss of host information. In this paper, we focus on improving payload and imperceptibility, and we propose an algorithm which is an extension of interpolationerror scheme using Particle Swarm Optimization (PSO) which better exploits estimation of missing pixel. The experimental results demonstrate that due to slight modification in interpolation-error technique, we achieve large hiding capacity and improved image quality compared with other schemes.
Reversible data hiding technique enables the exact recovery of original contents upon extraction ... more Reversible data hiding technique enables the exact recovery of original contents upon extraction of embedding data. Many conventional watermarking algorithms that have been proposed so far, suffer from the problem of low embedding capacity. In many applications huge amount of data is required to embed and exact recovery of host image is also needed. Luo's additive interpolation-error expansion technique [1] is a high capacity reversible method for data embedding without zero loss of host information. In this paper, we focus on improving payload and imperceptibility, and we propose an algorithm which is an extension of interpolationerror scheme using Particle Swarm Optimization (PSO) which better exploits estimation of missing pixel. The experimental results demonstrate that due to slight modification in interpolation-error technique, we achieve large hiding capacity and improved image quality compared with other schemes.
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