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Recently, compressive sensing (CS) has been successfully used in inverse synthetic aperture radar (ISAR) imaging. Since the exact sparse reconstruction, i.e., -norm constraint, is NP hard, -norm relaxation is widely used at the cost of performance degradation in the sparseness of the solution. The performance of existing CS-based ISAR imaging algorithms is sensitive to the regularized...
In this paper we present a case-study about recent breakthroughs of three-dimensional (3D) super-resolution live-cell imaging through thick specimens (50 - 150um). This technology is enabling the deep understanding of cellular mechanism by obtaining very detailed 3D descriptions of cells. In particular, we discuss the image analysis problems related to the accurate localization of single molecules...
In the paper we present a method for segmentation of insects from the Insect Soup images. The method enables reliable segmentation of insects of variable size, shape and color. After segmentation, a set of properties are assigned to each segmented insect which enables classification into different categories. The approach was successfully applied on two different types of real life images: images...
This note extends the superset method for sparse signal recovery from bandlimited measurements to the two-dimensional case. The algorithm leverages translation-invariance of the Fourier basis functions by constructing a Hankel tensor, and identifying the signal subspace from its range space. In the noisy case, this method determines a superset which then needs to undergo pruning. The method displays...
In this paper, we present a technique to remove the noise of a depth map while fill the missing regions of the depth map. Generally, the depth map is degraded during the sensing process, thermal noise, the condition of the atmosphere, and the occlusion by the objects. Different to the previous works which only adopt the joint image filters directly, we propose an automatic multi-resolution approach...
The goal of the work was to understand the impact on clinical measures of timing resolution for time-of-flight (TOF) fully-3D iterative reconstruction. We compared TOF impact to that from use of a PET detector response model. Sixteen FDG-avid features in 13 whole-body FDG studies acquired on a TOF-capable PET/CT system were used. A NEMA image quality phantom was also studied for comparison and reconstruction...
The Logan plot is a graphical method for reversible tracer bindings. The bias and uncertainties of this method have previously been analyzed with respect to noise, but little is known about the direct effects from varying the time sampling scheme. This study aims to investigate the effect of time sampling on the binding potential from the reference Logan plot.
We present a simulations study of the collimator sensitivity/resolution compromise as it affects the image quality of hot lesions in SPECT iterative reconstruction. We investigate three parallel-beam hexagonal-hole collimators with resolution in the center of the field of view equal to 11 mm, 15 mm, and 19 mm. We scan the Esser hot-rod phantom with 60 views and we reconstruct the images using MLEM...
Electronic portal mega-electronvolt (MV) monitoring for radiation therapy is very important for tumor localization. Furthermore, in the latest systems, before the radiation treatment, the patient is also positioned on the treatment bed with a flat-panel detector (FPD) based kilo-electronvolt (kV) CT scan for better soft tissue visibility. In the article we prove by measurement and imaging that a regular...
To have a unique solution of an ill-posed inverse problem, the usual way is to embed prior information in terms of regularizer or smoothness criterion. In this work, both the inverse mechanism (the relationship of blur and sharp patches) and the smoothness prior are learned simultaneously from the image itself, in multiple scales. We have shown experimentally that the proposed method outperform the...
This paper describes a novel method for single-image super-resolution (SR) based on a neighbor embedding technique which uses coupled feature spaces under surveillance scenarios. For surveillance face images, traditional neighbor embedding SR approaches could not offer counterintuitive results because consistency between high resolution images and low resolution images is destroyed by serious noise...
Single-image superresolution has become a widely-studied subject in image processing in recent years. Although considerable effort has been devoted in this context to contour enhancement, much less has been done to improve the textures of a degraded image. In this study, we present a novel algorithm which utilizes the power-law spectra of approximated 1/f processes, fitting a model of degraded natural...
We present in this paper a fast single image defogging method that uses a novel approach to refining the estimate of amount of fog in an image with the Locally Adaptive Wiener Filter. We provide a solution for estimating noise parameters for the filter when the observation and noise are correlated by decorrelating with a naively estimated defogged image. We demonstrate our method is 50 to 100 times...
The super-resolution approach has attracted substantial attention in the field of image processing in view of its capability of providing higher resolution from low resolution image sequences. Interesting techniques have been developed and practical results have been obtained. However, in several theoretical investigations, good results are often corroborated by simulations, which limits the use of...
The swallowing process affects several aspects of one's welfare, as nutrition, hydration, respiration and hearing. Magnetic resonance imaging (MRI) has been a valuable tool to study swallowing, since it is a non-invasive procedure that can dynamically capture the shapes of the tongue and other elements involved in the process. The resolution enhancement of the MRI frames support directly diseases...
Localization of a single fluorescent particle with sub-diffraction limit accuracy is a key merit in fluorescence microscopy. Implementation of nonlinear filtering algorithms prior the localization process can improve the localization accuracy of standard existing methods and also enable the localization of overlapping particles, allowing the use of increased fluorophore activation density, and thereby...
An optimized occlusion detection method for true orthophoto make is proposed in this paper, aimed at solving the occlusion and shadow problems caused by rectification using digital surface model (DSM). This method draws lessons from sweep way of angle-based detection method and idea of radial tracing detection method. It adds three judge rules to the occlusion detection process to increase its executing...
To enhance high frequency details of image super-resolution restoration, an algorithm based on improved MAP estimation is proposed. In this paper, POCS and MAP are combined in a special way. POCS is used in the MAP estimation so that advantages of the both algorithms can be taken. Experiment shows it is effective by comparing with the results of typical MAP method.
This paper addresses important computer vision problem of defining a measure for the strength (intensity) of edges in an image. The importance of the problem arises from the fact that images are typically represented in the multi - colour RGB format, hence each pixel requires more than one parameter to be defined. The α image is created using local colour statistics based on the size of the neighbourhood,...
The contribution of computer graphics in geophysics mainly embodies on the application of scientific computing visualization. In order to obtain the structural features and spatial distribution of various types of stratigraphic structure surface, it is necessary to carry out visual analysis on gigantic seismic data. However, the process of signal-noise separation requires enormous operations before...
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