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We present a PDE-based method for increasing the S/N ratio in noisy fluorescence image sequences where particle motion has to be measured quantitatively. The method is based on a novel accurate discretization of 3-D non linear anisotropic diffusion filtering, where the third dimension is the time t in the image sequence, using well adapted diffusivities. We have applied this approach to fluorescence...
In this paper, we propose a new switching median filter with signal dependent thresholds designed by a genetic algorithm (GA). The switching median filter detects noise-corrupted pixels based on a threshold. Then it restores only the detected pixels. The present switching median filter deals with the random-valued impulse noises, whose distribution is ideally assumed as a uniform distribution. In...
This paper proposes an additive watermarking on sparse or compressible coefficients of the host image in presence of blurring and additive noise degradation. The sparse coefficients are obtained through basis pursuit (BP). Watermark recovery is done through deblurring and performance is studied here for Wiener and fast total variation deconvolution (FTVD) techniques; the first one needs the actual...
Inverse halftoning techniques are known to introduce visible distortions (typically, blurring or noise) into the reconstructed image. To reduce the severity of these distortions, we propose a novel training approach for inverse halftoning algorithms. The proposed technique uses a coupled dictionary (CD) to match distorted and original images via a sparse representation. This technique enforces similarities...
The article is devoted to the instrumental means of the design of video data link, which are mounted on board the aircraft. The information concerning the possibilities of the program model use for the choice of the basic hosts and image translation options via physical "channel with gaps" is given in the article.
Ultrasound (US) imaging is widely used in clinical diagnostics as it is an economical, portable, painless, comparatively safe, and non-invasive real-time tool. However, the image quality of US imaging is severely affected by the presence of speckle noise during the acquisition process. It is essential to achieve speckle-free high resolution US imaging for better clinical diagnosis. In this paper,...
Total generalized variation (TGV) is a generalization of total variation (TV). This method has gained more and more attention in image processing due to its capability of reducing staircase effects. As the existence of high order regularity, TGV tends to blur edges, especially when noise is excessive. In this paper, we propose an iterative weighted total generalized variation (WTGV) model to reconstruct...
In general, an image degraded by blurring or defocusing is restored by deconvolution using a substantially constant PSF. However, in the case of a confocal laser microscope, there is a problem that the PSF varies according to the depth of focus. In order to overcome this problem, we adopt the iterative approach to estimate the PSF by a blind deconvolution. In order to confirm the effectiveness of...
Stochastic Resonance(SR) enhances the weak signal by using noise, providing a new way to process the weak signal in the strong noise background. This paper tries to give out a new way of image processing based on bistable Stochastic Resonance and Weiner Filtering. The image is firstly processed by bistable Stochastic Resonance. Then the output image is optimized by Weiner Filtering. The results are...
Subspace methods are a powerful tool to recover unknown filters by looking at the second order statistics of various signals originating from the same source (also called a SIMO problem). An extension to the multiple source case is also possible and has been investigated in the literature. In this paper we show how the blind superresolution problem can be solved by this tool. We first present the...
A procedure to determine the point spread function (PSF) of a two-dimensional SEM imaging system based on experimental data is presented. The specimen required for capture by the imaging system is simple to manufacture, and only requires a sharp edge to be of use. An overview is given of caveats that exist at each stage of the process, in addition to a breakdown of the process itself. Results based...
Two methods of the orthogonal spectra extrapolation problem are considered in this paper. Both solutions are based on the application of multi-valued neural element as a filter and as an extrapolator. The first method consist of approximation of the spectra in the higher frequency part using an iterative approximation and multi-valued non-linear filtering. The second method is reduced to the prediction...
The desire to view smaller and smaller attributes within biological specimens means that confocal microscopes are often used at the limit of their resolution. For quantitative analysis of smaller sized attributes, and as a necessary preprocessing stage for automatic recognition and classification of objects it is essential that confocal images are restored. A fast new hybrid statistical restoration...
In this paper, a Markov Random Field (MRF)-based method is presented. MRF methods are based on a probabilistic representation of a image processing problem; the problem is represented as the maximization of a probability measure computed starting from input data for all possible solutions. The optimization process is often computationally expensive. The coupled problem of restoring and extracting...
This work addresses the problem of generalized multisensor Hidden Markov Chain estimation with application to unsupervised restoration. A Hidden Markov Chain is said to be "generalized" when the exact nature of the noise components is not known; we assume however, that each of them belongs to a finite known set of families of distributions. The observed process is a mixture of distributions...
Images and videos are often captured in poor light conditions, resulting in low-contrast images that are corrupted by acquisition noise. To recreate a high-quality image for visual observation, the captured image must be denoised and contrastenhanced. Conventional methods perform these two tasks in two separate stages: an image is first denoised, followed by an enhancement procedure. In this paper,...
In this work, we present a technique designed for improving the subjective quality of still and video images presenting lack of sharpness. The technique employs a wavelet image representation based on edges extracted at different resolution levels by smoothed differential operators [1], and makes use of non-linear processing in the multiresolution edge domain. In this contribution, after a concise...
This paper deals with denoising of color video sequences using improved median-based filters appropriate for realtime implementations. In the paper, it is proven that application of prediction error processing results in improved efficiency of video restoration. The basic idea is to predict a pixel value by using a nonlinear filter, and then to calculate the prediction error by a comparison with the...
Filtering and restoration aim to improve the quality of an image to facilitate its interpretation. Most of these algorithms require a priori information about the degradation affecting the image. In the context of blind image processing, when no a priori information is available, the nature of the degradation has to be identified from the observed image. This operation is essential to select the algorithm...
A novel median-based filter having the effectiveness in the removal of impulse noise with high probability is proposed in this paper. The proposed filter is a kind of switching scheme-based median filters, and consists of two main parts: one detects impulse noise (impulse detecotor), another removes impulse noise (noise removal filter). First, we propose a novel impulse detector based on the directional...
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