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Sparse representation based image restoration techniques have shown to be successful in solving various inverse problems such as denoising, in painting, and super-resolution, etc. on natural images and videos. In this paper, we explore the use of sparse representation based methods specifically to restore the degraded document images. While natural images form a very small subset of all possible images...
A locally adaptive shrinkage Bayesian estimate for medical ultrasonography denoising is proposed by exploiting the correlation among image sparse coding. The Laplacian distribution is used to model the coding coefficients. The paper deduces the MAP estimate formula and adaptive threshold. Simulation experiments are carried out to show the effectiveness of the new method. Results demonstrate that compared...
It is a truth universally acknowledged that "a picture is worth a thousand words". The emerge of digital media has taken this saying to a complete new level. By using steganography, one can hide not only 1000, but thousands of words even in an average sized image. This article presents various types of techniques used by modern digital steganography, as well as the implementation of the...
A novel compressive sampling scheme suitable for highly scalable hardware implementations is presented. The scheme utilizes an identical pseudo-random sequence for every image column, therefore reducing in-pixel hardware complexity and allowing measurement matrix generation in a single clock cycle. As a result, high frame rates and low power consumption are achievable with an acceptable reduction...
This paper presents a novel incremental Σ-Δ ADC using two-step conversion and the fully-floating double-sampling integrator to greatly reduce the converting time. With a special procedure to solve the accuracy loss problem, the resolution of ADC is improved by one bit at the same time. What's more, another comparison is added during the conversion to detect redundant pixels in the image so that data...
This paper presents a comparison of a series of image quality metrics. Nine full-reference metrics of varying complexity are used to sort a number of different sets of corrupted images. Within each set, images are ranked from highest to lowest quality, using each of the nine metrics. The degree of similarity between each of these nine rank-orders is then statistically assessed. Results suggest that...
In this work, we propose a new encryption method of still images based on the affine encryption principle for achieve a transposition and perform some manipulations to reduce the quantity of bits. The application of this method on images, gave a high degree of safety and a minimum processing time proportional to the number of pixels, during the encryption and the decryption. The comparison of this...
Visual quality of color images is an important aspect in various applications of digital image processing and multimedia. A large number of visual quality metrics (indices) has been proposed recently. In order to assess their reliability, several databases of color images with various sets of distortions have been exploited. Here we present a new database called TID2013 that contains a larger number...
Due to the availability of many sophisticated image processing tools, a digital image forgery is nowadays very often used. One of the common forgery method is a copy-move forgery, where part of an image is copied to another location in the same image with the aim of hiding or adding some image content. Numerous algorithms have been proposed for a copy-move forgery detection (CMFD), but there exist...
The increasing attractiveness and trust on digital photography has given rise to new acceptability issues in the field of image forensics. There are many advantages to using digital images. Digital cameras produce immediate images, allowing the photographer to outlook the images and immediately decide whether the photographs are sufficient without the postponement of waiting for the film and prints...
This paper presents a robust denoising model for high-frequency artifacts resulted by compressing images into JPEG. In this model, the authors used only simple evaluation value named Extended Three-valued Increment Sign (ETIS). ETIS represents the relationship of adjacent pixels, which one is brighter or almost the same. The authors expected that ETIS difference between Compressed Image and Noise...
In this paper, we propose block level video steganalysis method. Current steganalysis methods detect steganograms at frame level only. In this paper, we present a new steganalysis method using correlation of pattern noise between consecutive frames as feature. First we extract the pattern noise from each frame and obtain difference between consecutive frames pattern noise. Later we divide the difference...
In this paper, a simple and robust watermarking algorithm using balanced multiwavelet transform is proposed. The latter transform we use achieves simultaneous orthogonality and symmetry without requiring any input prefiltering or border extending. This reduction in computational complexity makes the transform a good candidate for real-time watermarking implementations. Novelty of the system lies in...
Copy-move is a common used forgeries in digital image tampering. In this paper, a non block-matching based fast method to detect image copy-move forgery is proposed exploiting phase correlation. Results of experiments indicate that the proposed method is valid in detecting the image region duplication and quite robust to additive noise and blurring.
Impulsive noise in a compressed measurement signal can be detected by the energy distribution of the reconstructed sparse signal. In this paper, the fast preprocessing for impulsive noise rejection for a compressed measurement image signal is proposed. An image is sparsified by octave-tree wavelet transform with db8 as the mother wavelet. The impulsive noise is detected via the change in the ratio...
Real-time simultaneous high intensity focused ultrasound (HIFU) therapy and imaging allows for tracking tissue movement and monitoring feedback from a treated target. In ultrasound image guided HIFU using an integrated HIFU/imaging transducer, the reflected strong HIFU interference received by the imaging transducer degraded imaging quality. In order to figure out this problem, we have previously...
Using coding artificial point can match the homonymy points during multiple images automatically in the photogrammetry. A method of identifying and locating 8 bits encoded points automatically has been presented in this paper. The experimental results show that the accuracy of center coordinate of encoding point reaches sub-pixel level. And decoding method is simple. The robust of decoding and recognition...
In this paper, we propose an effective image compression noise reduction system based on the total variation (TV) regularization method. Our system allows the removal of MPEG-2 compression noise such as mosquito noise and blocky noise without losing picture sharpness. This method is particularly useful for HDTV terrestrial broadcasting with insufficient transmission bandwidth for noise-free HDTV pictures...
An algorithm of digital watermarking based on hyper chaos sequence and the discrete fractional Fourier transform (DFRFT) is proposed. First, the watermark image is scrambled in the spatial domain. The original image and the watermark image are discrete fractional Fourier transformed respectively with different order. Secondly, the watermark image's real part and imaginary part are encrypted by the...
Digital watermarking is a huge research area which is progressively growing. It covers theoretical studies, novel techniques, attacks and performance analysis. An embedded watermark may unintentionally or inadvertently be impaired by such processing. Other types of processing may be applied with the explicit goal of hindering watermark reception. In watermarking terminology, an “attack” is any processing...
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