Fluoroscopy devices provide real-time, radiographic movies of patient and it is widely utilized as support for surgery and in diagnostic. Low X-ray dose results in intense quantum noise, which is modeled as Poisson-di...
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ISBN:
(纸本)9781479923724
Fluoroscopy devices provide real-time, radiographic movies of patient and it is widely utilized as support for surgery and in diagnostic. Low X-ray dose results in intense quantum noise, which is modeled as Poisson-distributed stochastic signal. Recently, a specific filter technique was introduced to suppress quantum noise in fluoroscopy. Filter operation relies on the estimation of the relationship between noise variance and mean pixel intensity relative to the fluoroscopy device setup. By holding this information, noise suppression can be exclusively performed by averaging the only adjacent data in space and time that have high probability to belong to the noise statistics. The performances of this filter were compared to those of another filter based on the maximum a posteriori probability criterion designed for Poisson's noise suppression. The performances of the two filters, in terms of SNR and PSNR, resulted very similar, but they are a bit lower than more sophisticated filters such as BM3Dc. Nevertheless, they offer a simplicity of the algorithms that allows their realization in real-time to support interventional fluoroscopy application.
An airborne EO/IR (electro-optical/infrared) camera system comprises of a suite of sensors, such as a narrow and wide field of view (FOV) EO and mid-wave IR sensors. EO/IR camera systems are regularly employed on mili...
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ISBN:
(纸本)9781628415902
An airborne EO/IR (electro-optical/infrared) camera system comprises of a suite of sensors, such as a narrow and wide field of view (FOV) EO and mid-wave IR sensors. EO/IR camera systems are regularly employed on military and search and rescue aircrafts. The EO/IR system can be used to detect and identify objects rapidly in daylight and at night, often with superior performance in challenging conditions such as fog. There exist several algorithms for detecting potential targets in the bearing elevation grid. The nonlinear filtering problem is one of estimation of the kinematic parameters from bearing and elevation measurements from a moving platform. In this paper, we developed a complete model for the state of a target as detected by an airborne EO/IR system and simulated a typical scenario with single target with 1 or 2 airborne sensors. We have demonstrated the ability to track the target with 'high precision' and noted the improvement from using two sensors on a single platform or on separate platforms. The performance of the Extended Kalman filter (EKF) is investigated on simulated data. image/video data collected from an IR sensor on an airborne platform are processed using an image tracking by detection algorithm
Information of lens aberration of lithographic tools is important as it directly affects the intensity distribution in the image plane. Zernike polynomials are commonly used for a mathematical description of lens aber...
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ISBN:
(数字)9781510617520
ISBN:
(纸本)9781510617520;9781510617513
Information of lens aberration of lithographic tools is important as it directly affects the intensity distribution in the image plane. Zernike polynomials are commonly used for a mathematical description of lens aberrations. Due to the advantage of lower cost and easier implementation of tools, image based measurement techniques have been widely used. Lithographic tools are typically partially coherent systems that can be described by a bilinear model, which entails time-consuming calculations and does not lend a simple and intuitive relationship between lens aberrations and the resulted images. Previous methods for retrieving lens aberrations in such partially coherent systems involve through-focus image measurements and time-consuming iterative algorithms. In this work, we propose a method for aberration measurement in lithographic tools, which only requires measuring two images of intensity distribution. Two linear formulations are derived in matrix forms that directly relate the measured images to the unknown Zernike coefficients. Consequently, an efficient non-iterative solution is obtained.
A fuzzy bit allocation method, applicable to many rate control algorithms targeted for variable rate video applications, is proposed in this paper. In low-delay video communication applications, a constant short-term ...
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In this research, data acquired by Unmanned Aerial Vehicles (UAVs) are primarily used to detect and track moving objects which pose a major security threat along the United States southern border. Factors such as came...
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In this research, data acquired by Unmanned Aerial Vehicles (UAVs) are primarily used to detect and track moving objects which pose a major security threat along the United States southern border. Factors such as camera motion, poor illumination and noise make the detection and tracking of moving objects in surveillance videos a formidable task. The main objective of this research is to provide a less ambiguous image data for object detection and tracking by means of noise reduction, image enhancement, video stabilization, and illumination restoration. The improved data is later utilized to detect and track moving objects in surveillance videos. An optimization based image enhancement scheme was successfully implemented to increase edge information to facilitate object detection. Noise present in the raw video captured by the UAV was efficiently removed using search and match methodology. Undesired motion induced in the video frames was eliminated using block matching technique. Moving objects were detected and tracked by using contour information resulting from the implementation of adaptive background subtraction based detection process. Our simulation results shows the efficiency of these algorithms in processing noisy, un-stabilized raw video sequences which were utilized to detect and track moving objects in the video sequences. (C) 2014 Published by Elsevier B.V.
Present article deals with a noble approach for designing the photonic crystal devices by using information about diffraction patterns at different frequencies;it is useful for optimizing an element designed to operat...
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A generically valid proof of uniqueness for the surface solution to shape from shading is presented. Local surface solutions around a singular point have at most a fourfold ambiguity. These results apply to a reflecta...
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ISBN:
(纸本)0818620625
A generically valid proof of uniqueness for the surface solution to shape from shading is presented. Local surface solutions around a singular point have at most a fourfold ambiguity. These results apply to a reflectance function corresponding to illumination symmetric around the viewer direction of a uniform-albedo Lambertian object. Generic surfaces are studied, and their properties are established. It is noted that the proof may lead to new, faster algorithms for shape recovery. Questions of existence are also discussed. It is argued that most images are impossible in the sense that they cannot be a depiction of any physical object. The proof is based on ideas of dynamical systems theory and global analysis.
The three step search (TSS) has been used for real time video processing and low bit-rate video communications because of reduced computations, simplicity, and reasonable performance in the motion estimation. Other mo...
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The three step search (TSS) has been used for real time video processing and low bit-rate video communications because of reduced computations, simplicity, and reasonable performance in the motion estimation. Other modified algorithms of TSS have been studied for speed of computation and the performance of motion vector estimation. This paper proposes a new algorithm (Fast Three Step Search) for more efficient reduction of computational complexity. It is shown that the proposed algorithm (FTSS) is very efficient in computation while keeping the reasonable performance.
The traditional method of raising your hand in a classroom to say "present ma’am" or "yes ma’am" or whatever other things you would say is kind of fading away, imageprocessing is becoming increa...
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In this paper, we present how 3D split and merge segmentation using topological and geometrical structuring with an Oriented Boundary Graph may be optimized by parallel algorithms. This structuring allows to implement...
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ISBN:
(纸本)9788086943169
In this paper, we present how 3D split and merge segmentation using topological and geometrical structuring with an Oriented Boundary Graph may be optimized by parallel algorithms. This structuring allows to implement efficiently split and merge operations, but since these treatments have often to be applied with large images, we have studied how to improve performances by parallelizing this process. After a short description of the structuring 0 model and its construction, we describe algorithms for parallelizing the construction of the structuring and describe how this model can be maintained while using parallel processes. We explain the way of partitioning data for use with multiprocessor systems, and extension for use with NUMA architectures and graphics processing units (GPU) is described. Exemples on two medical images of different sizes is presented and execution time will be given.
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