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DCT-Based Blind Watermarking of 3D Models
Abstract
To propose robust blind watermarking methods of 3D models based on DCT. First a 3D mesh models will be mapped to a 2D parametric mesh with a kind of planar parameterization method, geometric signals are then transformed into 2D signals. Then a DCT-based watermark scheme is proposed to embed the watermark into some DCT coefficients. The watermark can be detected without the original 3D models. Experimental results show that the embedded watermark is robust against various geometry signal processing.
... Zhang et al. utilized the coordinate difference between each two points in the model to construct a difference histogram, further improving the embedding capacity of the algorithm [2]. Zhou et al. proposed a 3D model transformation domain information hiding algorithm based on DCT [3]. Ren et al. pro-posed a 3D model information hiding algorithm based on distance features and volume integral invariants, which effectively improved the robustness of the algorithm while ensuring invisibility [4]. ...
In order to solve the problem of low capacity in current 3D model information hiding algorithms based on single carrier, we propose a 3D information hiding algorithm based on point cloud increment building upon the research findings of existing single carrier information hiding technology for 3D models. Firstly, the algorithm performs hierarchical clustering on the 3D model using a plane fitting technique, completing the preprocessing of secret information. Secondly, employing a point simplification and compression method, we classify the layered point cloud into four distinct point sets. Finally, utilizing the spatial characteristics between the four point sets, double secret information was embedded through vertex segmentation in two sets of point sets. The application of double embedding ideas in the algorithm greatly improves robustness. The segmentation of points increases the number of point clouds and makes the model smoother, while increasing the algorithm’s capacity. The experimental results show that the information hiding algorithm proposed in this article outperforms the comparison algorithm in all aspects, breaking the balance between robustness, invisibility, and capacity to a certain extent, and has a positive impact on the development of national network security.
Three robust blind watermarking methods of 3D models based on Octree are proposed in this paper: OTC-W, OTP-W and Zero-W. Primary Component Analysis and Octree partition are used on 3D meshes. A scrambled binary image for OTC-W and a scrambled RGB image for OTP-W are separately embedded adaptively into the single child nodes at the bottom level of Octree structure. The watermark can be extracted without the original image and 3D model. Those two methods have high embedding capacity for 3D meshes. Meanwhile, they are robust against geometric transformation (like translation, rotation, uniform scaling) and vertex reordering attacks. For Zero-W, higher nodes of Octree are used to construct 'Zerowatermark', which can resist simplification, noise and remeshing attacks. All those three methods are fit for 3D point cloud data and arbitrary 3D meshes.
The article reports that due to the proliferation of the World-Wide Web, a huge amount of multimedia content text, graphics, images, video, and audio are available for browsing and downloading by millions of users worldwide over the network. As a result, security and copyright issues have become important problems in research and applications. Current copyright laws are perhaps inadequate for dealing with digital data, leading to interest in developing other copyright protection mechanisms, including digital watermarking techniques. Digital watermarking is applicable in copyright protection, ownership assertion, and integrity checks in multimedia content. A visible watermark typically contains a visual message or a company logo indicating ownership of the image. An invisible watermarked image is visually very similar but not necessarily identical to the original unmarked image. The existence of such a watermark can be determined only through a watermark extraction or detection algorithm.
Data hiding, a form of steganography, embeds data into digital media for the purpose of identification, annotation, and copyright. Several constraints affect this process: the quantity of data to be hidden, the need for invariance of these data under conditions where a "host" signal is subject to distortions, e.g., lossy compression, and the degree to which the data must be immune to interception, modification, or removal by a third party. We explore both traditional and novel techniques for addressing the data-hiding process and evaluate these techniques in light of three applications: copyright protection, tamper-proofing, and augmentation data embedding.
This paper presents a nonlinear control algorithm to address the
motion synchronization problem for a dual-cylinder electrohydraulic (EH)
lift system. A two-step design approach is applied that utilized linear
multiple input-multiple output (MIMO) robust control technique to design
an outer-loop motion synchronization controller. A nonlinear single
input-single output (SISO) perturbation observer-based pressure-force
controller is designed for each of the lift cylinders as the inner-loop
controller to handle the nonlinearities associated with the EH
actuators. Experimental results on a 2-cylinder lift system verified the
effectiveness of the proposed approach
This paper addresses the problem of noise attenuation for
multichannel data. The proposed filter utilizes adaptively determined
data-dependent coefficients based on a novel distance measure which
combines vector directional with vector magnitude filtering. The special
case of color image processing is studied as an important example of
multichannel signal processing
Multimedia watermarking technology has evolved very quickly during
the last few years. A digital watermark is information that is
imperceptibly and robustly embedded in the host data such that it cannot
be removed. A watermark typically contains information about the origin,
status, or recipient of the host data. In this tutorial paper, the
requirements and applications for watermarking are reviewed.
Applications include copyright protection, data monitoring, and data
tracking. The basic concepts of watermarking systems are outlined and
illustrated with proposed watermarking methods for images, video, audio,
text documents, and other media. Robustness and security aspects are
discussed in detail. Finally, a few remarks are made about the state of
the art and possible future developments in watermarking
technology
This book constitutes the strictly refereed post-workshop proceedings of the First International Workshop on Information Hiding, held in Cambridge, UK, in May/June 1996, within the research programme in computer security, cryptology and coding theory organized by the volume editor at the Isaac Newton Institute in Cambridge.
Work on information hiding has been carried out over the last few years within different research communities, mostly unaware of each other's existence. The 26 papers presented define the state of the art and lay the foundation for a common terminology. This workshop is very likely to be seen at some point as one of those landmark events that mark the birth of a new scientific discipline.
This book presents the latest research in the area of multimedia data hiding paradigms. The book is divided into four parts and an appendix.
• The first part introduces multimedia signal processing and information hiding techniques. It includes multimedia representation, need for multimedia, digital watermarking fundamentals and requirements of watermarking.
• The second part describes the recent advances in multimedia signal processing.
• The third part presents information hiding techniques including steganography, secret sharing and watermarking.
• The final part of this book includes practical applications of intelligent multimedia signal processing and data hiding systems.
• Appendix includes source codes and/or executables related to the topics in some chapters. Interested readers are invited to use these programs.
This book will be valuable to both academia and industry. This book is directed to the final year undergraduate and junior postgraduate students. Researchers and professors in the departments of electrical/electronics/communication engineering, computer science, and relating departments will find this book useful.
With the increasing use of 3D geometry in industry, algorithms processing geometric signals become more and more important. Despite the promising recent progress of digital geometry processing, it still lacks a unified solution to address all issues of geometry like digital image processing. With solid theoretic foundation, the framework for digital signal processing over arbitrary meshes presented in this paper meets this requirement. The main idea of the framework is to construct global spherical (or planar) parameterizations for meshes, transform all attributes of meshes into spherical (or planar) signals and use spherical (or planar) orthonormal analysis tool to process these signals. With the framework, all image processing techniques can be extended to 3D meshes. This paper also describes how to perform signal filtering, multi-resolution editing and geometry compression and gives some experimental results.
There are very few examples of true vector filters known for
colour images. The authors introduce a new class of filter based on
convolution with hypercomplex masks, and present three colour edge
detecting filters inspired by the Prewitt, Sobel and Kirsch filters.
These filters, when applied to a colour image, produce an almost
greyscale image with colour edges where the original image had a sharp
change of colour. They rely on a three-space rotation about the grey
line of RGB space, implemented with the rotation operator R[]R<sup>-1
</sup> where R is a quaternion and R-1 is its inverse. Pixels
of similar colour corresponding to opposing positions in the filter
masks cancel to give a grey or monochromatic result, while pixels of
different colour are differenced in a vector sense to give coloured edge
pixels. The linearity of the new filters is discussed and the paper
concludes with a discussion of the impulse response of a hypercomplex
filter
It is difficult to precisely detect all impulsive noise in color images due to the nonstationarity caused by edges and fine details. For many pixels, we can not absolutely classify them as noisy or noise-free, but can only describe them using the likelihood that they are corrupted by impulsive noise. Based on this consideration, we present a new filtering solution to removing impulsive noise from color images. The proposed method first utilizes the unit transforms of quaternions to represent the chromaticity difference of two color pixels, and then divides the image into noise-free and possible noisy pixels. Finally it performs adaptive weighted vector median filtering operations on only the possible noisy pixels to suppress noise. The new weighting mechanism is based on a joint spatial/quaternion-chromaticity criterion, which ensures that pixels with different contamination likelihoods have different contributions to the filter's output. The extensive simulation results indicate that the proposed method significantly outperforms some other well-known multichannel filtering techniques.
We present a new impulsive noise removal method, which combines a switching mechanism and adaptive weighted median filtering techniques. By utilizing four Laplacian operators and median-based comparison techniques to classify the image pixels into thin-line pixels, noise-free pixels, and noisy ones, the developed solution applies adaptive weighted median filtering operations only in the detected noisy locations to suppress impulsive noise, and keeps the other pixels unchanged. The simulation results exhibit the excellent performance gains of the proposed solution in suppressing impulsive noise with different contamination ratios over other prior-art methods in terms of both objective measurements and visual image quality.
In this paper, an integrated fuzzy controller is proposed to achieve a synchronous positioning objective for a dual-cylinder electro-hydraulic lifting system with unbalanced loadings, system uncertainties, and disturbances. The control system consists of one-fuzzy coordination controller for both cylinders and an individual cylinder controller, comprised of a feedforward controller, and a fuzzy tracking controller, for each of the hydraulic cylinders. In the integrated fuzzy controller design, the fuzzy coordination controller is responsible for dispatching motion synchronization commands to the individual cylinder controllers. Each cylinder controller then adaptively enforces the position tracking to its controlled actuator. The experimental results show that the proposed integrated fuzzy controller design can effectively achieve the objective of position synchronization in the dual-cylinder electro-hydraulic system, with maximum synchronization error within ±4mm.
This book presents the latest research in the area of multimedia data hiding paradigms. The book is divided into four parts and an appendix. The first part introduces multimedia signal processing and information hiding techniques. It includes multimedia representation, need for multimedia, digital watermarking fundamentals and requirements of watermarking. The second part describes the recent advances in multimedia signal processing. The third part presents information hiding techniques including steganography, secret sharing and watermarking. The final part of this book includes practical applications of intelligent multimedia signal processing and data hiding systems. Appendix includes source codes and/or executables related to the topics in some chapters. Interested readers are invited to use these programs.
A physiologically plausible model of colour vision, based on the CIE 1931 standard colorimetric observer, is shown to provide a colour order system giving reasonably good predictions of the unique-hue loci, of constant-hue loci, and of constant-saturation loci, as judged by comparison with the Munsell and NCS systems, for daylight illumination. When combined with a chromatic-adaptation transform of the von Kries type, the model is also shown to give quite good predictions for real surface colours seen in tungstenlight (SA) illumination.
Median filters are widely used in color image processing. In this paper a new fuzzy median filter is introduced, suitable
for the removal of impulse noise in color images. In order to apply a median operator, some kind of ordering of vectors is
required. Thus, a vector ordering scheme in the HSV color space using fuzzy if-then rules is described and then the median
value operator is defined. The weighted fuzzy median is also studied. This filter performs significantly better in impulse
noise removal, compared to other reported median filters. Experimental and comparative results of the application of the proposed
filter and other similar reported filters, exhibit the superiority of the proposed method when applied to degraded color images.
This paper deals with an experimental optimization problem of the controller gains for an electro-hydraulic position control system through evolution strategies (ESs)-based method. The optimal controller gains for the control system are obtained by maximizing fitness function designed specially to evaluate the system performance. In this paper, for an electro-hydraulic position control system which would represent a hydraulic mill stand for the roll-gap control in plate hot-rollings, the time delay controller (TDC) is designed, and three control parameters of this controller are directly optimized through a series of experiments using this method. It is shown that the near-optimal value of the controller gains is obtained in about 5th generation, which corresponds to approximately 150 experiments. The optimal controller gains are experimentally confirmed by inspecting the fitness function topologies that represent system performance in the gain spaces. It is found that there are some local optimums on a fitness function topology so that the optimization of the three control parameters of a TDC by manual tuning could be a task of great difficulty. The optimized results via the ES coincide with the maximum peak point in topologies. It is also shown that the proposed method is an efficient scheme giving economy of time and labor in optimizing the controller gains of fluid power systems experimentally.
A new adaptive vector median filtering scheme taking the advantage of the optimal filtering situation and the robust order-statistic theory, is provided. An adaptive control is based on the set of vector-valued order-statistics with the smallest distances to other samples in the input set.
In this paper, a self-tuning procedure for the automatic adaptation of the parameters for the PI controller of a construction unit testing apparatus is proposed. The automatic adaptation is documented on the test bed of a construction unit testing apparatus. The self-tuning procedure is used for the commencement of operations of the process with the PI controller, and for the adaptation of the parameters to changes to the working point, as part of the self-tuning procedure of the closed loop.
Tansmission mechanisms usually play an important role in mechanical systems. This type of device is responsible for transferring energy to a remote site, and may change the type of motion, as needed. However, the inherent friction will handicap the overall system performance. This nonlinear property brings about severe stability problems, including the limit cycle, which strongly constrains the accuracy and bandwidth of any mechanical system. This paper presents a tuning strategy for PID controllers to avoid the phenomenon of stick slip caused by friction in transmission systems. In addition, to achieve sufficiently smooth motion, a cycloidal trajectory profile adopted from cam theory is also applied. Precise positioning can therefore be accomplished by employing the cycloidal profile, together with appropriate controller parameters. Encouraging control performance is demonstrated experimentally. Comparisons between the proposed approach and an adaptive control method are also shown.
This paper presents a novel approach for 3D surface filtering over two-manifold meshes. A robust spherical parameterization algorithm is proposed to transform the input surface into a spherical vector function/signal. This signal is then decomposed into frequency domain using spherical harmonic transforms. Finally, traditional filtering techniques are generalized to process such spherical signals in either the frequency or spatial domain. Our major contribution is the two-phase spherical parameterization algorithm, which can handle meshes with complex shapes by incorporating local parameterization into the progressive mesh. A number of experimental examples demonstrate the potential of our algorithm.
The article asserts that information and knowledge play a decisive, if not paramount, role in business performance. The right information and content at the right time are keys to success and therefore have tremendous value for individuals, businesses, even the entire society. Protecting information and content is of the utmost importance for content providers as well as end users of the related information. Contrary to popular belief, law enforcement authorities do not prevent crimes in our society, they investigate crimes after the criminal act takes place and gather evidence toward the eventual indictment and conviction of criminals. Although copyright protection is the original motivation for developing digital watermarks, the technology has found a multitude of potential applications not anticipated by pioneers in the field. When a watermark holds executable content, the marked document can perform actions and operations and interact with the application environment. To make watermarks work, application protocols have to solve real-world piracy problems.
Digital watermarking has been proposed as a solution to the problem of copyright protection of multimedia data in a networked environment. It makes possible to tightly associate to a digital document a code allowing the identification of the data creator, owner, authorized consumer, and so on. In this paper a new watermarking algorithm for digital images is presented: the method, which operates in the frequency domain, embeds a pseudo-random sequence of real numbers in a selected set of DCT coefficients. After embedding, the watermark is adapted to the image by exploiting the masking characteristics of the human visual system, thus ensuring the watermark invisibility. By exploiting the statistical properties of the embedded sequence, the mark can be reliably extracted without resorting to the original uncorrupted image. Experimental results demonstrate that the watermark is robust to several signal processing techniques, including JPEG compression, low pass and median filtering, histogram equalization and stretching, dithering, addition of Gaussian noise, resizing, and multiple watermarking.
Human color vision is based on three light-sensitive pigments. The isolation and sequencing of genomic and complementary DNA
clones that encode the apoproteins of these three pigments are described. The deduced amino acid sequences show 41 +/- 1 percent
identity with rhodopsin. The red and green pigments show 96 percent mutual identity but only 43 percent identity with the
blue pigment. Green pigment genes vary in number among color-normal individuals and, together with a single red pigment gene,
are proposed to reside in a head-to-tail tandem array within the X chromosome.
This paper presents a secure (tamper-resistant) algorithm for watermarking images, and a methodology for digital watermarking that may be generalized to audio, video, and multimedia data. We advocate that a watermark should be constructed as an independent and identically distributed (i.i.d.) Gaussian random vector that is imperceptibly inserted in a spread-spectrum-like fashion into the perceptually most significant spectral components of the data. We argue that insertion of a watermark under this regime makes the watermark robust to signal processing operations (such as lossy compression, filtering, digital-analog and analog-digital conversion, requantization, etc.), and common geometric transformations (such as cropping, scaling, translation, and rotation) provided that the original image is available and that it can be successfully registered against the transformed watermarked image. In these cases, the watermark detector unambiguously identifies the owner. Further, the use of Gaussian noise, ensures strong resilience to multiple-document, or collusional, attacks. Experimental results are provided to support these claims, along with an exposition of pending open problems.
With the development of DLP projection technology, DLP is gradually occupying LCD projector market. To the limitations and faults of mechanical color wheel in conventional DLP projection system, we study illumination structure based on high-power LED system. An innovative method is proposed. Through establishing test platforms, parameters of illumination system and constant current modules for high-power LED are obtained. The results indicate that this method simplifies the structure of digital constant current source, reduces costs of system and improves accuracy. In the application of DLP stereo prototype projector, the proposed method meets the demands of high efficiency, rich color, long lifetime etc. Thus, more colorful and vivid image is showed, three-dimensional video performed by our innovative projector will become more fluent in the near future.
Digital Light ProcessingTM (DLPTM)
projection technology, based on the Digital Micromirror Device<sup>TM
</sup> light modulator is currently used in a wide variety of display
applications to create high quality imagery. In this paper we present an
overview of the electronics architecture of a DLPTM
technology based projector. Descriptions of the DMDTM
modulator drive methods and data formatting electronics are presented,
as well as a brief summary of the video and graphics processing
architectures
A new type of edge-detecting filter is presented, based on a new
type of image convolution in which colour images are convolved with a
pair of quaternion-valued (hypercomplex) masks. When applied to a colour
image, the new filter converts areas of smoothly-varying colour to
shades of grey, and generates colours in regions where colour (but not
intensity) edges occur in the image. The result may be easily
thresholded for chromaticity to produce an edge image exhibiting colour
only where the original image exhibited a sharp change of colour
By analyzing quaternion rotation theory, the color difference between two color pixels can be represented in quaternion form. Based on this representation of color difference, an efficient color-impulse detector for switching vector median filters is presented. Extensive simulations indicate that the proposed algorithm provides a significant improvement over many of the existing vector filtering techniques in suppressing impulses with different noise ratios. In particular, the proposed approach effectively preserves the fine thin lines and other detail features. The low computational complexity is also one of its advantages
An adaptive nearest neighbor multichannel filter
- K N Plataniotis
- D Androutsos
- Ann Venetsanopoulos
- KN Plataniotis