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We propose a framework to extend corner feature detection in standard rectangular images with less distortion to distorted circular images captured with fisheye lenses. To solve two problems of nonuniformity of spatial resolution and spherical polar coordinates singularity, our approach makes use of a modification in the Yin-Yang grid, which is an overset grid consisting of two latitude/longitude...
This paper deals with an unsupervised approach for land change detection and extraction using bitemporal and multispectral remotely sensed images. It is a statistical approach based on multivariate alteration detection (MAD) transformation combined with a new ChiMerge thresholding method. As opposed to most other multivariate change detection schemes the MAD technique is invariant to affine transformations...
Terahertz technology is one of emerging technologies that has a potential to change our life. There is considerable interest in using electromagnetic terahertz pulses for imaging purposes. In this paper we presented initial results for improving the resolution of terahertz pulsed imaging system utilizing methodology of super-resolution reconstruction. We attempt to reconstruct an super-resolution(SR)...
In this work, we consider the problem of detecting target objects in remote sensing imagery; such as detecting rooftops, trees, or cars in color/hyperspectral imagery. Many detection algorithms for this problem work by assigning a decision statistic (or “confidence”) to all, or a subset, of spatial locations in the data. A threshold is then applied to the statistics to identify detections. The detection...
Sparse Representation and Compressive Sensing (CS) theory has gained an increasing interest during the last years in many application fields, including SAR tomography. The latter offers the possibility to perform a focusing, beyond the classical 2D (azimuth-range) domain, along other dimensions: f.i., elevation and velocity. The literature, however, lacks of an assessment of the improvement of CS...
Spatially entangled photon states are used in experiments addressing fundamental properties of quantum mechanics as well as practical applications [1]. Thereby, the use of these states demands for time-saving detection mechanisms, capable of measuring coincidences between spatially separated photons with high spatial and temporal resolution. In this work, we demonstrate coincidence detection of spatially...
Exploitation of the statistical properties of classical or non-classical light sources is the cause of fascinating new applications. For the two last decades, ghost imaging has emerged as a way to form images of an object with a Single Point Detector (SPD) that does not have spatial resolution [1-5]. By taking into account space-time duality in optics, the extension of the results of spatial ghost...
Autoradiography is a method that allows to take ex-vivo images of thin sections of tissue labelled with a radioactive tracer. In the present work, we aim to study the feasibility of autoradiography with CMOS (Complementary Metal Oxide Semiconductor) Mimosa-28 by using 2-Deoxy-2-18F-fluoro-D-glucose (18F-FDG). Autoradiography allows a functional imaging pixelated with a resolution equivalent to optical...
In this paper, an effective edge-directed low-complex interpolation based method is proposed for 1080i Full HD to Progressive 8K Ultra HD video post-processing. The proposed spatial-domain post-processing technology is composed of two processing stages, where the first stage is the three-scan lines based de-interlacing process for 1080i Full HD to 1080p Full HD conversion, and the second stage is...
We have defined a hyperspectral imager based on micro-mirror MEMS array, that features easily adaptable spectral resolution, adjustable acquisition time, and high spatial resolution independent of spectral resolution. We present the development of an integrated research prototype of the imager, that allows the control of both the micro-mirrors array and CMOS data reading from the same FPGA board,...
The structural analysis of nerve fibers of the human brain is an important topic in current neuroscience. To obtain information about neural connections with micrometer resolution, polarized light imaging (3D PLI) of histological brain sections is well suited. In our application, both high-resolution (HR, 64µm in-plane pixel size) and ultra-high resolution (ultra-HR, 1.3µm) 3D PLI data of human brain...
Object detection in high resolution remote sensing images is a crucial yet challenging problem for many applications. With the development of satellite and sensor technologies, remote sensing images attain very high spatial resolution, giving rise to the employment of many computer vision algorithms. Therefore, the object detection is usually formalized as a supervised classification task. In this...
Traditional Hyperspectral Imaging (HSI) architectures face a fundamental trade-off between spatial, spectral and temporal resolution, requiring repetitive scanning of the scene. A new generation of Snapshot Spectral Imagers exploit Spectrally Resolvable Detector Arrays to sample the entire hyperspectral cube from a single frame. However these systems are also limited since only a single band is captured...
In PET systems with a geometry different from a closed ring, the Time of Flight (TOF) of the annihilation photons appears to be relevant. Such a system capability helps to compensate the missing angular information that generates artifacts on the reconstructed images. In this work, two ASIC designs are evaluated for their use in PET systems having accurate coincidence resolving times (CRT) while preserving...
In this work we report on GATE simulation studies of DC-SPECT, a body contouring system designed for cardiac imaging applications. The design concept of the DC-SPECT is based on multiple simultaneous view of the heart enabled by the use of laser processed CsI:Tl detector modules with high intrinsic detector resolution. Our theoretical and GATE simulation results show that we can obtain ∼0.081% system...
We previously built a high-resolution PET scanner (PawPET) using 8 mm thick Lutetium Oxyorthosilicate (LSO) detectors, but it suffers from poor sensitivity. From our prior work we know that unpolished 0.5 mm pitch arrays with Toray reflector are challenging to decode at depths greater than 8 mm. We hypothesize that decoding will improve by polishing the crystal surfaces. We also know that polished...
PET is the most sensitive imaging technique in the field of nuclear medicine. However, the single count rate is typically 10 times higher than the coincidence count rate. This means that there are a lot of pairs of undetected annihilation photons. For single gamma imaging, Compton imaging is known as the only method to obtain directional information of an incoming gamma ray without using collimators...
Using pulsed neutron imaging, the distributions of absolute values of nuclide densities and temperatures of the sample can be estimated. However, the images obtained by the pulsed neutron imaging have a low spatial resolution because of the performance limitations of the detector. On the other hand, X-ray radiograms have higher spatial resolution compared with the neutron images. To obtain higher-resolution...
Spatial resolution is one of the most important performance in PET system. Higher spatial resolution can give more information about the region of interest in animal PET imaging. In this work, we implement a high resolution (approximate 0.7 mm) all digital animal PET system using improved Trans-PET detectors. The improved detector module uses 24×24 crystal array for higher intrinsic spatial resolution...
Several groups are actively investigating the performance of thick continuous crystals to determine the potential of this detector design. One method to alter the behavior of this detector is to etch laser induced optical barriers (LIOBs) into the crystal. This work explores the performance of thick continuous detectors etched partly into the crystal in a grid pattern. As a motivation for this study,...
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