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The foreground detection is a key processing in crowd motion analysis containing abnormal behavior detections and crowd density estimations. This paper proposes a new foreground detection approach called optical flow and background model (OFBM) based on Lucas-Kanade optical flow and Gaussian background model methods. This approach overcomes the shortages of optical flow and background subtract. Experimental...
A single-exposure generalized phase-shifting digital holography based on a wave-splitting method. A phase-encoded reference wave is used for phase-shifting. Using the known amplitude and phase distributions of the reference wave, the fully complex amplitude of the object wave is obtained. The proposed method requires not devised optical systems but ordinary imaging devices, such as CCD cameras. A...
In this paper a vision-based system for safe autonomous landing of a helicopter-based Unmanned Aerial Vehicle (UAV) is presented. The remote user selects target areas from high resolution aerial or satellite images. These areas are tracked by a feature-based image matching algorithm that identifies natural landmarks and gives feedbacks for control purposes. The main novelty of the proposed approach...
Diabetic retinopathy (DR) is the damage to the eye's retina that occurs with long-term diabetes, which can eventually lead to blindness. Screening programs for DR are being introduced, however, an important prerequisite for automation is the accurate localization of the main anatomical features in the image, notably the optic disc (OD) and the macula. A series of interesting algorithms have been proposed...
In order to satisfy the real time request of optical Imaging Simulation System for small celestial bodies, this paper proposed a simulation method of the camera based on physical model, which is based on OpenGL pinhole imaging model and simulate optical camera parameters with graphic functions. By combining with rendering to texture and graphics hardware programming technologies, the article got sequence...
In this paper, we investigate the performance of pulse-coupled neural networks (PCNNs) to detect the damage caused by an earthquake. PCNN is an unsupervised model in the sense that it does not need to be trained, which makes it an operational tool during crisis events when it is crucial to produce damage maps as soon as the post-event images are available. The damage map resulting from PCNN was validated...
Satellite observations are currently of major importance in geosciences. Remote sensing is a strong tool to study atmospheric and earth phenomena. In this work, we propose a new motion estimation approach with application to dust storm tracking from remote sensing images. Dynamic natural phenomena in the atmosphere are generally turbulent due to a high Reynolds number. Meteorological images are still...
Specific architectures for different low level vision modalities have been developed and described using reconfigurable hardware. Each of them tries to solve a single low level vision problem: optical flow, disparity, segmentation, tracking, etc. We introduce a novel architecture that includes multiple processing engines in a massively parallel low level vision processing engine of very high complexity...
The image of a beacon on the photosensitive plane of pointing sensor in a receiving terminal is usually considered as the acquisition and tracking target of optical antenna for the Free Space Optical Communications (FSOC). The receiver processes the acquired image to ascertain the position of the transmitting terminal by the relevant algorithm. The tracking veracity of the algorithm to a target position...
An approach to classifying retinal images using a histogram based representation is described. More specifically, a two stage Case Based Reasoning (CBR) approach is proposed, to be applied to histogram represented retina images to identify Age-related Macular Degeneration (AMD). To measure the similarity between histograms, a time series analysis technique, Dynamic Time Warping (DTW), is employed...
Glaucoma is a disease characterized by elevated intraocular pressure (IOP). This increased IOP leads to damage of optic nerve axons at the back of the eye, with eventual deterioration of vision. CDR is a key indicator for the detection of glaucoma. The existing approaches determined the CDR using manual threshold analysis which is fairly time consuming. This paper proposes two methods to extract the...
Artificial olfaction systems have been investigated since more than two decades on alleged property of similarities between the receptive field of natural receptors and artificial sensors. Due to the limited number of sensors embedded in these systems the complexity of electronic noses is generally too low to allow the application of olfaction processing models. Actually the literature there are several...
Depth estimation has long been a fundamental problem both in robotics science and in computer vision. Various methods have been developed and implemented in a large number of applications. Despite the rapid progress in the field the last few years, computation remains a significant issue of the methods employed. In this work, we have implemented two different strategies for inferring depth, both of...
Recently, the studies of human motion analysis have attracted great attention among the researches in the field of biomechanics, medicine and sports by analyzing the joints, postures, and movements of the human. Our research focuses on analyzing the joints movement of a professional golfer. We represent those joint movements with an articulate stick human model. This paper presents a method for tracking...
The design and construction of Non-Imaging Planar Concentrator (NIPC), capable of producing much more uniform spatial irradiance and reasonably high concentration ratio, have been presented in our previous research paper. In this study, we would carry out a comprehensive analysis through the numerical simulation on solar flux distribution at the target by considering all the important criteria to...
Myopia is a growing concern in many societies. In extremely high myopia, pathological myopia, which can cause visual loss, can occur. Pathological myopia is also accompanied by various visually perceivable symptoms on the retina, such as peripapillary atrophy. PAMELA is an automatic system for the detection of pathological myopia through the presence of peripapillary atrophy. In this paper, we describe...
In order to improve the precision, speed, integration and reliability of the linear CCD system, which was used to detect the sub-pixel edge of picture, a new digital system based on auto focusing was designed. The system captures the image of the tested work piece through a CCD, puts the image data into computer, gathers coordinate of tested edge of work by the method of digital image processing and...
A composite method for detecting the centerline of straight light stripe is presented in this paper. In order to locate the image of stripe, a conditional dilation algorithm based on mathematical morphology is proposed to extract the regions of interest (ROI), and a shape factor is applied to eliminate the disturbance regions, so the straight light stripes are determined finally. Barycenter method...
Holographic display system that uses six phase-only spatial light modulators (SLMs) performs holographic reconstructions from the phase-hologram of a point cloud that is extracted from 3D object. The SLMs are tiled as a three by two matrix on a virtual planar surface. The alignment is successful and the display system generates large holographic reconstructions. The proposed system can be used either...
Synthetic and genetically encoded optical switch probes and lock-in detection methods provide a means to modulate and isolate fluorescence signals from the optical switch and protein complexes of interest against un-modulated background sources. In this paper we propose an improved method for optical lock-in detection (OLID) fluorescence microscopy that can significantly enhance image contrast of...
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