510 research outputs found
Survey of the Use of Steganography over the Internet
This paper addressesthe use of Steganography over the Internet by terrorists. There were ru-mors in the newspapers that Steganography is being used to covert communication between terrorists, without presenting any scientific proof. Niels Provos and Peter Honeyman conducted an extensive Internet search where they analyzed over 2 million images and didnât find a single hidden image. After this study the scientific community was divided: some believed that Niels Provos and Peter Honeyman was conclusive enough other did not. This paper describes what Steganography is and what can be used for, various Steganography techniques and also presents the studies made regarding the use of Steganography on the Internet.Steganography, Secret Communication, Information Hiding, Cryptography
Towards Blind Watermarking: Combining Invertible and Non-invertible Mechanisms
Blind watermarking provides powerful evidence for copyright protection, image
authentication, and tampering identification. However, it remains a challenge
to design a watermarking model with high imperceptibility and robustness
against strong noise attacks. To resolve this issue, we present a framework
Combining the Invertible and Non-invertible (CIN) mechanisms. The CIN is
composed of the invertible part to achieve high imperceptibility and the
non-invertible part to strengthen the robustness against strong noise attacks.
For the invertible part, we develop a diffusion and extraction module (DEM) and
a fusion and split module (FSM) to embed and extract watermarks symmetrically
in an invertible way. For the non-invertible part, we introduce a
non-invertible attention-based module (NIAM) and the noise-specific selection
module (NSM) to solve the asymmetric extraction under a strong noise attack.
Extensive experiments demonstrate that our framework outperforms the current
state-of-the-art methods of imperceptibility and robustness significantly. Our
framework can achieve an average of 99.99% accuracy and 67.66 dB PSNR under
noise-free conditions, while 96.64% and 39.28 dB combined strong noise attacks.
The code will be available in https://github.com/rmpku/CIN.Comment: 9 pages, 9 figures, 5 table
Embedding Error Based Data Hiding in Color Images for Distortion Tolerance
In this paper, a data hiding scheme with distortion tolerance for color image is proposed. Data hiding is used to embed secret information into the cover image for secure transmission and protecting copyright. The secret information feasibly a text or an image. To protect the copyright of a true color image, a signature (a watermark), which is represented by a sequence of binary data, is embedded in the color image. In this proposed scheme, we first calculate the embedding error between the cover image and the secret information. Based on this embedding error, the stego image is computed then the embedded data are extracted by the extraction procedure. This scheme can tolerate some distortion such us salt and pepper noise, Gaussian noise, uniform noise, and JPEG lossy compression when transmitting a stego image through any network. Experimental results and discussions reveal that the proposed scheme tolerates those distortions with acceptable image quality
Print-Scan Resilient Text Image Watermarking Based on Stroke Direction Modulation for Chinese Document Authentication
Print-scan resilient watermarking has emerged as an attractive way for document security. This paper proposes an stroke direction modulation technique for watermarking in Chinese text images. The watermark produced by the idea offers robustness to print-photocopy-scan, yet provides relatively high embedding capacity without losing the transparency. During the embedding phase, the angle of rotatable strokes are quantized to embed the bits. This requires several stages of preprocessing, including stroke generation, junction searching, rotatable stroke decision and character partition. Moreover, shuffling is applied to equalize the uneven embedding capacity. For the data detection, denoising and deskewing mechanisms are used to compensate for the distortions induced by hardcopy. Experimental results show that our technique attains high detection accuracy against distortions resulting from print-scan operations, good quality photocopies and benign attacks in accord with the future goal of soft authentication
Robust digital watermarking for compressed 3D models based on polygonal representation
Multimedia has recently played an increasingly important role in various domains, including Web applications, movies, video game and medical visualization. The rapid growth of digital media data over the Internet, on the other hand, makes it easy for anyone to access, copy, edit and distribute digital contents such as electronic documents, images, sounds and videos. Motivated by this, much research work has been dedicated to develop methods for digital data copyright protection, tracing the ownership, and preventing illegal duplication or tampering. This paper introduces a methodology of robust digital watermarking based on a well-known spherical wavelet transformation, applied to 3D compressed model based on polygonal representation using a neural network. It will be demonstrated in this work that applying a watermarking algorithm on a compressed domain of a 3D object is more effective, efficient, and robust than when applied on a normal domain
The Wiltshire Wills Feasibility Study
The Wiltshire and Swindon Record Office has nearly ninety thousand wills in its care. These records are neither adequately catalogued nor secured against loss by facsimile microfilm copies. With support from the Heritage Lottery Fund the Record Office has begun to produce suitable finding aids for the material. Beginning with this feasibility study the Record Office is developing a strategy to ensure the that facsimiles to protect the collection against risk of loss or damage and to improve public access are created.<p></p>
This feasibility study explores the different methodologies that can be used to assist the preservation and conservation of the collection and improve public access to it. The study aims to produce a strategy that will enable the Record Office to create digital facsimiles of the Wills in its care for access purposes and to also create preservation quality microfilms. The strategy aims to seek the most cost effective and time efficient approach to the problem and identifies ways to optimise the processes by drawing on the experience of other similar projects. This report provides a set of guidelines and recommendations to ensure the best use of the resources available for to provide the most robust preservation strategy and to ensure that future access to the Wills as an information resource can be flexible, both local and remote, and sustainable
Sparse Regression Codes for Multi-terminal Source and Channel Coding
We study a new class of codes for Gaussian multi-terminal source and channel
coding. These codes are designed using the statistical framework of
high-dimensional linear regression and are called Sparse Superposition or
Sparse Regression codes. Codewords are linear combinations of subsets of
columns of a design matrix. These codes were recently introduced by Barron and
Joseph and shown to achieve the channel capacity of AWGN channels with
computationally feasible decoding. They have also recently been shown to
achieve the optimal rate-distortion function for Gaussian sources. In this
paper, we demonstrate how to implement random binning and superposition coding
using sparse regression codes. In particular, with minimum-distance
encoding/decoding it is shown that sparse regression codes attain the optimal
information-theoretic limits for a variety of multi-terminal source and channel
coding problems.Comment: 9 pages, appeared in the Proceedings of the 50th Annual Allerton
Conference on Communication, Control, and Computing - 201
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