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Recursive Non-Local Means Filter For Video Denoising, Redha A. Ali, Russell C. Hardie 2017 University of Dayton

Recursive Non-Local Means Filter For Video Denoising, Redha A. Ali, Russell C. Hardie

Electrical and Computer Engineering Faculty Publications

In this paper, we propose a computationally efficient algorithm for video denoising that exploits temporal and spatial redundancy. The proposed method is based on non-local means (NLM). NLM methods have been applied successfully in various image denoising applications. In the single-frame NLM method, each output pixel is formed as a weighted sum of the center pixels of neighboring patches, within a given search window.

The weights are based on the patch intensity vector distances. The process requires computing vector distances for all of the patches in the search window. Direct extension of this method from 2D to 3D, for video ...


Optimizing An Electron's Path To Ionization Using A Genetic Algorithm, Jason Bennett, Kevin Choice 2017 Ursinus College

Optimizing An Electron's Path To Ionization Using A Genetic Algorithm, Jason Bennett, Kevin Choice

Physics and Astronomy Summer Fellows

A Rydberg atom is an atom with a highly excited and weakly bound valence electron. A widespread method of studying quantum mechanics with Rydberg atoms is to ionize the electron and measure its arrival time. We use a Genetic Algorithm (GA) to control the electron's path to ionization. The Rydberg electron's energy levels are strongly shifted by the presence of an electric field. The energy levels shift and curve, but never cross. At an avoided crossing the electron can jump from one level to the next. By engineering the electric field's time dependence, we thereby control the ...


Growth And Magnetooptical Properties Of Anisotropic Tbf3 Single Crystals, Uygun V. Valiev, Denis N. Karimov, Gary W. Burdick, Rakhim Rakhimov, Vasiliy O. Pelenovich, Dejun Fu 2017 Wuhan University

Growth And Magnetooptical Properties Of Anisotropic Tbf3 Single Crystals, Uygun V. Valiev, Denis N. Karimov, Gary W. Burdick, Rakhim Rakhimov, Vasiliy O. Pelenovich, Dejun Fu

Faculty Publications

The present paper investigates the Faraday effect and absorption and luminescence spectra of single-crystal TbF3 measured at 90 K and 300 K. The optical-quality single-phase TbF3 crystals (structural type β-YF3) were grown by the Bridgman technique. Faraday rotation angles were measured at remagnetization along the [100] crystallographic axis. Low temperature optical measurements were carried out along the [100] axis. “Quasi-doublet” sublevels with energy at 0 cm-1, 65 cm-1 and 190 cm-1, and also a singlet sublevel with energy at 114 cm-1 located in the ground 7F6 multiplet were determined from the low temperature ...


Comparing Multiple Turbulence Restoration Algorithms Performance On Noisy Anisoplanatic Imagery, Michael Armand Rucci, Russell C. Hardie, Alexander J. Dapore 2017 Air Force Research Laboratory

Comparing Multiple Turbulence Restoration Algorithms Performance On Noisy Anisoplanatic Imagery, Michael Armand Rucci, Russell C. Hardie, Alexander J. Dapore

Russell C. Hardie

In this paper, we compare the performance of multiple turbulence mitigation algorithms to restore imagery degraded by atmospheric turbulence and camera noise. In order to quantify and compare algorithm performance, imaging scenes were simulated by applying noise and varying levels of turbulence. For the simulation, a Monte-Carlo wave optics approach is used to simulate the spatially and temporally varying turbulence in an image sequence. A Poisson-Gaussian noise mixture model is then used to add noise to the observed turbulence image set. These degraded image sets are processed with three separate restoration algorithms: Lucky Look imaging, bispectral speckle imaging, and a ...


Recursive Non-Local Means Filter For Video Denoising With Poisson-Gaussian Noise, Redha A. Almahdi, Russell C. Hardie 2017 University of Dayton

Recursive Non-Local Means Filter For Video Denoising With Poisson-Gaussian Noise, Redha A. Almahdi, Russell C. Hardie

Russell C. Hardie

In this paper, we describe a new recursive Non-Local means (RNLM) algorithm for video denoising that has been developed by the current authors. Furthermore, we extend this work by incorporating a Poisson-Gaussian noise model. Our new RNLM method provides a computationally efficient means for video denoising, and yields improved performance compared with the single frame NLM and BM3D benchmarks methods. Non-Local means (NLM) based methods of denoising have been applied successfully in various image and video sequence denoising applications. However, direct extension of this method from 2D to 3D for video processing can be computationally demanding. The RNLM approach takes ...


Analysis Of Various Classification Techniques For Computer Aided Detection System Of Pulmonary Nodules In Ct, Barath Narayanan Narayanan, Russell C. Hardie, Temesguen Messay 2017 University of Dayton

Analysis Of Various Classification Techniques For Computer Aided Detection System Of Pulmonary Nodules In Ct, Barath Narayanan Narayanan, Russell C. Hardie, Temesguen Messay

Russell C. Hardie

Lung cancer is the leading cause of cancer death in the United States. It usually exhibits its presence with the formation of pulmonary nodules. Nodules are round or oval-shaped growth present in the lung. Computed Tomography (CT) scans are used by radiologists to detect such nodules. Computer Aided Detection (CAD) of such nodules would aid in providing a second opinion to the radiologists and would be of valuable help in lung cancer screening. In this research, we study various feature selection methods for the CAD system framework proposed in FlyerScan. Algorithmic steps of FlyerScan include (i) local contrast enhancement (ii ...


On The Simulation And Mitigation Of Anisoplanatic Optical Turbulence For Long Range Imaging, Russell C. Hardie, Daniel A. LeMaster 2017 University of Dayton

On The Simulation And Mitigation Of Anisoplanatic Optical Turbulence For Long Range Imaging, Russell C. Hardie, Daniel A. Lemaster

Russell C. Hardie

We describe a numerical wave propagation method for simulating long range imaging of an extended scene under anisoplanatic conditions. Our approach computes an array of point spread functions (PSFs) for a 2D grid on the object plane. The PSFs are then used in a spatially varying weighted sum operation, with an ideal image, to produce a simulated image with realistic optical turbulence degradation. To validate the simulation we compare simulated outputs with the theoretical anisoplanatic tilt correlation and differential tilt variance. This is in addition to comparing the long- and short-exposure PSFs, and isoplanatic angle. Our validation analysis shows an ...


Recursive Non-Local Means Filter For Video Denoising, Redha A. Ali, Russell C. Hardie 2017 University of Dayton

Recursive Non-Local Means Filter For Video Denoising, Redha A. Ali, Russell C. Hardie

Russell C. Hardie

In this paper, we propose a computationally efficient algorithm for video denoising that exploits temporal and spatial redundancy. The proposed method is based on non-local means (NLM). NLM methods have been applied successfully in various image denoising applications. In the single-frame NLM method, each output pixel is formed as a weighted sum of the center pixels of neighboring patches, within a given search window. The weights are based on the patch intensity vector distances. The process requires computing vector distances for all of the patches in the search window. Direct extension of this method from 2D to 3D, for video ...


Simulation Of Anisoplanatic Imaging Through Optical Turbulence Using Numerical Wave Propagation With New Validation Analysis, Russell C. Hardie, Jonathan D. Power, Daniel A. LeMaster, Douglas R. Droege, Szymon Gladysz, Santasri Bose-Pillai 2017 University of Dayton

Simulation Of Anisoplanatic Imaging Through Optical Turbulence Using Numerical Wave Propagation With New Validation Analysis, Russell C. Hardie, Jonathan D. Power, Daniel A. Lemaster, Douglas R. Droege, Szymon Gladysz, Santasri Bose-Pillai

Russell C. Hardie

We present a numerical wave propagation method for simulating imaging of an extended scene under anisoplanatic conditions. While isoplanatic simulation is relatively common, few tools are specifically designed for simulating the imaging of extended scenes under anisoplanatic conditions. We provide a complete description of the proposed simulation tool, including the wave propagation method used. Our approach computes an array of point spread functions (PSFs) for a two-dimensional grid on the object plane. The PSFs are then used in a spatially varying weighted sum operation, with an ideal image, to produce a simulated image with realistic optical turbulence degradation. The degradation ...


Block Matching And Wiener Filtering Approach To Optical Turbulence Mitigation And Its Application To Simulated And Real Imagery With Quantitative Error Analysis, Russell C. Hardie, Michael Armand Rucci, Barry K. Karch, Alexander J. Dapore 2017 University of Dayton

Block Matching And Wiener Filtering Approach To Optical Turbulence Mitigation And Its Application To Simulated And Real Imagery With Quantitative Error Analysis, Russell C. Hardie, Michael Armand Rucci, Barry K. Karch, Alexander J. Dapore

Russell C. Hardie

We present a block-matching and Wiener filtering approach to atmospheric turbulence mitigation for long-range imaging of extended scenes. We evaluate the proposed method, along with some benchmark methods, using simulated and real-image sequences. The simulated data are generated with a simulation tool developed by one of the authors. These data provide objective truth and allow for quantitative error analysis. The proposed turbulence mitigation method takes a sequence of short-exposure frames of a static scene and outputs a single restored image. A block-matching registration algorithm is used to provide geometric correction for each of the individual input frames. The registered frames ...


Design And Implementation Of A Microscope Based On Magneto-Optic Effects, Yuxuan Liu 2017 Rose-Hulman Institute of Technology

Design And Implementation Of A Microscope Based On Magneto-Optic Effects, Yuxuan Liu

Graduate Theses - Physics and Optical Engineering

When light passes through a medium that is subjected to a strong magnetic field, its polarization state may change due to magneto-optic effects such as Faraday rotation. An imaging system based on this polarization change is designed and constructed. The imaging system is built around a magnetic pulse field generator and able to detect polarization change of the incident light due to magneto-optic effects. An automated scheme is implemented using LabView. The program is developed to integrate all hardware and conduct multiple measurements automatically to enhance sensitivity. Basic testing measurements are conducted to evaluate the performance of the system. A ...


Wave Propagation Inside Random Media, Xiaojun Cheng 2017 The Graduate Center, City University of New York

Wave Propagation Inside Random Media, Xiaojun Cheng

All Graduate Works by Year: Dissertations, Theses, and Capstone Projects

This thesis presents results of studies of wave scattering within and transmission through random and periodic systems. The main focus is on energy profiles inside quasi-1D and 1D random media.

The connection between transport and the states of the medium is manifested in the equivalence of the dimensionless conductance, g, and the Thouless number which is the ratio of the average linewidth and spacing of energy levels. This equivalence and theories regarding the energy profiles inside random media are based on the assumption that LDOS is uniform throughout the samples. We have conducted microwave measurements of the longitudinal energy profiles ...


Quantum Optical Interferometry And Quantum State Engineering, Richard J. Birrittella Jr 2017 The Graduate Center, City University of New York

Quantum Optical Interferometry And Quantum State Engineering, Richard J. Birrittella Jr

All Graduate Works by Year: Dissertations, Theses, and Capstone Projects

We highlight some of our research done in the fields of quantum optical interferometry and quantum state engineering. We discuss the body of work for which our research is predicated, as well as discuss some of the fundamental tenants of the theory of phase estimation. We do this in the context of quantum optical interferometry where our primary interest lies in the calculation of the quantum Fisher information as it has been shown that the minimum phase uncertainty obtained, the quantum Cramer-Rao bound, is saturated by parity-based detection methods. We go on to show that the phase uncertainty one obtains ...


Basic Vision Research With Clinical Applications And Science Education Assessments, Andrew Wilson 2017 The University of Maine

Basic Vision Research With Clinical Applications And Science Education Assessments, Andrew Wilson

Electronic Theses and Dissertations

Visual Acuity (VA) examinations are one of the most commonly conducted medical assessment throughout the world. Recent advances in computer technology allows for new forms of visual assessment to be conducted. In Part I of this thesis I demonstrate the capability of an automated computer program named VISION to assess human visual acuities. Different color combinations of an object against a background emitted from a computer screen are used to examine a variety of human color vision acuities. Results indicated a large difference in acuity scores between human subjects tested with these different color combinations. A single human subject exhibits ...


Optical Physics Of Rifle Scopes, Ryan Perry 2017 California Polytechnic State University, San Luis Obispo

Optical Physics Of Rifle Scopes, Ryan Perry

Physics

Optical systems are typically consist of multiple lenses and mirrors and are used in a wide variety of fields. While there exist a variety of setups, there are a few key concepts that are at the core of all of them. These could be used from the most advanced scientific research to a simple magnifying glass. They are also used in industry and consumer products such as glasses and cameras. We are going to go over these key concepts and show how they apply to telescopes, or more specifically rifle scopes. First, we will go over Snell's Law of ...


Multispectral Identification Array, Zachary D. Eagan 2017 California Polytechnic State University, San Luis Obispo

Multispectral Identification Array, Zachary D. Eagan

Computer Engineering

The Multispectral Identification Array is a device for taking full image spectroscopy data via the illumination of a subject with sixty-four unique spectra. The array combines images under the illumination spectra to produce an approximate reflectance graph for every pixel in a scene. Acquisition of an entire spectrum allows the array to differentiate objects based on surface material. Spectral graphs produced are highly approximate and should not be used to determine material properties, however the output is sufficiently consistent to allow differentiation and identification of previously sampled subjects. While not sufficiently advanced for use as a replacement to spectroscopy the ...


Time-Resolved Thz Conductivity Of An Intermediate Band Semiconductor, Elliot Weiss 2017 Macalester College

Time-Resolved Thz Conductivity Of An Intermediate Band Semiconductor, Elliot Weiss

Macalester Journal of Physics and Astronomy

Intermediate band materials have promising applications as affordable, highly efficient solar materials. However, intermediate band solar cells exhibit low efficiency to date. Carrier recombination is a critical process that limits efficiency. If electrons relax to the valence band before they can be collected, their energy is lost. To help understand the recombination dynamics and physical properties of intermediate band semiconductors, we obtain time-resolved THz conductivity measurements of the intermediate band semiconductor, GaPAsN, at various temperatures. From our results, we build a model that provides insight to the recombination dynamics of GaPAsN.


Conductivity Measurements Of A Thermoelectric Nanomaterial Through Thz Spectroscopy, Michaela S. Koller, James Heyman, Gunnar Footh 2017 Macalester College

Conductivity Measurements Of A Thermoelectric Nanomaterial Through Thz Spectroscopy, Michaela S. Koller, James Heyman, Gunnar Footh

Macalester Journal of Physics and Astronomy

In today’s society there is a great demand on energy output—in the United States alone we rely heavily on non-renewable energy sources. Thermoelectric materials may be able to be used to create more efficient energy systems or recover wasted heat from inefficient technologies. This paper focuses on the conductivity of a new thermoelectric material that incorporates copper into a tellurium nanowire PEDOT:PSS material. The addition of copper seems to increase the conductivity of the material, although the exact relationship between the percentage of copper to tellurium and its affect on the conductivity is uncertain from the results.


Studies In Mesoscopics And Quantum Microscopies, Zhenghao Ding, Gabriel C. Spalding 2017 Illinois Wesleyan University

Studies In Mesoscopics And Quantum Microscopies, Zhenghao Ding, Gabriel C. Spalding

Honors Projects

This thesis begins with a foundational section on quantum optics. The single-photon detectors used in the first chapter were obtained through the Advanced Laboratory Physics Association (ALPhA), which brokered reduced cost for educational use, and the aim of the single-photon work presented in Chapter 1 is to develop modules for use in Illinois Wesleyan's instructional labs beyond the first year of university. Along with the American Association of Physics Teachers, ALPhA encourages capstone-level work, such as Chapter 1 of this honors thesis, which is explicitly designed to play the role of passing on, to a next generation of physics ...


Comparing Multiple Turbulence Restoration Algorithms Performance On Noisy Anisoplanatic Imagery, Michael Armand Rucci, Russell C. Hardie, Alexander J. Dapore 2017 Air Force Research Laboratory

Comparing Multiple Turbulence Restoration Algorithms Performance On Noisy Anisoplanatic Imagery, Michael Armand Rucci, Russell C. Hardie, Alexander J. Dapore

Electrical and Computer Engineering Faculty Publications

In this paper, we compare the performance of multiple turbulence mitigation algorithms to restore imagery degraded by atmospheric turbulence and camera noise. In order to quantify and compare algorithm performance, imaging scenes were simulated by applying noise and varying levels of turbulence. For the simulation, a Monte-Carlo wave optics approach is used to simulate the spatially and temporally varying turbulence in an image sequence. A Poisson-Gaussian noise mixture model is then used to add noise to the observed turbulence image set. These degraded image sets are processed with three separate restoration algorithms: Lucky Look imaging, bispectral speckle imaging, and a ...


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