Search results for " Vision"

showing 10 items of 2709 documents

Conceptual spaces for computer vision representations

2001

A framework for high-level representations in computer vision architectures is described. The framework is based on the notion of conceptual space. This approach allows us to define a conceptual semantics for the symbolic representations of the vision system. In this way, the semantics of the symbols can be grounded to the data coming from the sensors. In addition, the proposed approach generalizes the most popular frameworks adopted in computer vision.

Conceptual spaceSettore ING-INF/05 - Sistemi Di Elaborazione Delle InformazioniLinguistics and LanguageHigh level computer visionArtificial IntelligenceComputer vision representationLanguage and Linguistic
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Automated detection of patient movement during a CBCT scan based on the projection data.

2015

Objectives To develop an automated procedure to detect patient motion on the projection images acquired during a cone beam computed tomography (CBCT) scan and to evaluate the method's feasibility on small real-world CBCT images in relation to visual assessment. Methods Based on optical flow theory, software was developed using the sequence of the projection images of a CBCT machine for automated detection of patient motion. Averaged acceleration vectors were used as measurement data and compared with visual assessment of the projection images displayed as video. Seventy-nine CBCT data sets (small field-of-view: 40 mm) from our patient database were selected in a sequential fashion and evalu…

Cone beam computed tomographyComputer scienceMovementOptical flowVideo RecordingSensitivity and SpecificityPathology and Forensic MedicineAccelerationSoftwareImaging Three-DimensionalHumansRadiology Nuclear Medicine and imagingDentistry (miscellaneous)Computer visionSensitivity (control systems)Projection (set theory)Pixelbusiness.industryPhantoms ImagingFrame (networking)Cone-Beam Computed TomographyFeasibility StudiesRadiographic Image Interpretation Computer-AssistedSurgeryArtificial intelligenceOral SurgerybusinessArtifactsAlgorithmsSoftwareOral surgery, oral medicine, oral pathology and oral radiology
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Metal artifact reduction in x-ray computed tomography: Inpainting versus missing value

2011

A comparison of algorithms for reduction of metal artifacts in x-ray cone beam computed tomography (CBCT) is presented. In the context of algebraic reconstruction techniques (ART) several inpainting algorithms in the image domain are evaluated against missing data strategies. A GPU-based iterative framework is employed for a meaningful comparison of both. Simulation results from an extended Shepp-Logan phantom and real world dental data are given.

Cone beam computed tomographyComputer sciencebusiness.industryComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISIONInpaintingContext (language use)Iterative reconstructionMissing dataMetal ArtifactComputer visionTomographyArtificial intelligencebusinessImage restorationComputingMethodologies_COMPUTERGRAPHICS2011 IEEE Nuclear Science Symposium Conference Record
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Alignment of cone beam computed tomography data using intra-oral fiducial markers.

2009

This article illustrates a new method to align and merge two partially overlapping volumes each of them generated by cone beam computed tomography (CBCT). The aggregate volume covers a larger area of investigation and is determined by localizing one fixed LEGO brick in both of the primal volumes. Based on the LEGO brick an approximate registration of the volumes is determined. Afterwards we improve the transformation by minimizing the difference in overlapping space. In this paper we present a method which automates these two steps and provides an aligned volume.

Cone beam computed tomographyMouthRadiological and Ultrasound Technologybusiness.industryComputer sciencePhantoms ImagingHealth InformaticsRadiography Dental DigitalCone-Beam Computed TomographyComputer Graphics and Computer-Aided DesignComputer Science::Computers and SocietyOpticsJawIntra oralHumansRadiology Nuclear Medicine and imagingComputer visionComputer Vision and Pattern RecognitionArtificial intelligencebusinessFiducial markerMerge (version control)Computerized medical imaging and graphics : the official journal of the Computerized Medical Imaging Society
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Motion Artifact Detection in Confocal Laser Endomicroscopy Images

2018

Confocal Laser Endomicroscopy (CLE), an optical imaging technique allowing non-invasive examination of the mucosa on a (sub)- cellular level, has proven to be a valuable diagnostic tool in gastroenterology and shows promising results in various anatomical regions including the oral cavity. Recently, the feasibility of automatic carcinoma detection for CLE images of sufficient quality was shown. However, in real world data sets a high amount of CLE images is corrupted by artifacts. Amongst the most prevalent artifact types are motion-induced image deteriorations. In the scope of this work, algorithmic approaches for the automatic detection of motion artifact-tainted image regions were develo…

Confocal laser endomicroscopyArtifact (error)Computer sciencebusiness.industryDeep learningCellular levelOral cavity01 natural sciencesMotion (physics)010309 optics03 medical and health sciences0302 clinical medicineOptical imaging030220 oncology & carcinogenesis0103 physical sciencesComputer visionArtificial intelligencebusinessReal world data
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Sa1611 Computer-Assisted Diagnosis of Confocal Laser Endomicroscopy (CLE) by a Novel Image Analysis and Semantic Annotation Method

2012

Confocal laser endomicroscopyPathologymedicine.medical_specialtySemantic annotationbusiness.industryGastroenterologymedicineRadiology Nuclear Medicine and imagingComputer visionArtificial intelligencebusinessGastrointestinal Endoscopy
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Wavelet analysis of human photoreceptoral response

2010

Feature detection of biomedical signals is crucial for deepening our knowledge of the physiological phenomena giving rise to them. To achieve this aim, even if many analytic approaches have been suggested only few are able to deal with signals whose features are time dependent, and to provide useful clinical information. In this work we use the wavelet analysis to extract peculiarities of the early response of the photoreceptoral human system, known as a-wave ERG-component. The analysis of the a-wave features is important since this component reflects the functional integrity of the two populations of photoreceptors, rods and cones whose activation dynamics are not well known. Moreover, in …

Congenital stationary night blindnessAchromatopsiagenetic structuresmedicine.diagnostic_testbusiness.industryWavelet analysis photoreceptoral response Achromatopsia Congenital Stationary Night Blindness.Wavelet transformFeature detection (nervous system)BiologyNeurophysiologymedicine.diseaseSettore FIS/07 - Fisica Applicata(Beni Culturali Ambientali Biol.e Medicin)Time–frequency analysisWaveletmedicineComputer visionsense organsArtificial intelligencebusinessNeuroscienceElectroretinography2010 3rd International Symposium on Applied Sciences in Biomedical and Communication Technologies (ISABEL 2010)
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On utilizing dependence-based information to enhance micro-aggregation for secure statistical databases

2011

Published version of an article in the journal: Pattern Analysis and Applications. Also available from the publisher at: http://dx.doi.org/10.1007/s10044-011-0199-9 We consider the micro-aggregation problem which involves partitioning a set of individual records in a micro-data file into a number of mutually exclusive and exhaustive groups. This problem, which seeks for the best partition of the micro-data file, is known to be NP-hard, and has been tackled using many heuristic solutions. In this paper, we would like to demonstrate that in the process of developing micro-aggregation techniques (MATs), it is expedient to incorporate information about the dependence between the random variable…

ConjectureTheoretical computer scienceVariablesComputer scienceCovariance matrixmedia_common.quotation_subjectmicro-aggregation techniqueVDP::Technology: 500::Information and communication technology: 550Mutually exclusive eventscomputer.software_genrePartition (database)CorrelationVDP::Mathematics and natural science: 400::Information and communication science: 420::Knowledge based systems: 425Artificial IntelligenceJoint probability distributionprojected variablesComputer Vision and Pattern RecognitionData miningmaximun spanning treeRandom variablecomputermedia_common
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A PARALLEL ALGORITHM FOR ANALYZING CONNECTED COMPONENTS IN BINARY IMAGES

1992

In this paper, a parallel algorithm for analyzing connected components in binary images is described. It is based on the extension of the Cylindrical Algebraic Decomposition (CAD) to a two-dimensional (2D) discrete space. This extension allows us to find the number of connected components, to determine their connectivity degree, and to solve the visibility problem. The parallel implementation of the algorithm is outlined and its time/space complexity is given.

Connected componentDegree (graph theory)Artificial IntelligenceDiscrete spaceBinary imageVisibility (geometry)Parallel algorithmComputer Vision and Pattern RecognitionTime complexityAlgorithmSoftwareMathematicsCylindrical algebraic decompositionInternational Journal of Pattern Recognition and Artificial Intelligence
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Detection and classification of microcalcifications clusters in digitized mammograms

2005

In the present paper we discuss a new approach for the detection of microcalcification clusters, based on neural networks and developed as part of the MAGIC-5 project, an INFN-funded program which aims at the development and implementation of CAD algorithms in a GRID-based distributed environment. The proposed approach has as its roots the desire to maximize the rejection of background during the analytical pre-processing stage, in order to train and test the neural network with as clean as possible a sample and therefore maximize its performance. The algorithm is composed of three modules: the image pre-processing, the feature extraction component and the Backpropagation Neural Network mod…

Connected componentNEURAL-NETWORKArtificial neural networkbusiness.industryComputer scienceFeature extractionCADGridGrayscaleBackpropagationMedical ImagingTransformation (function)Computer aided diagnosiDigital imagingComputer visionImage analysiArtificial intelligencebusinessMammography
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