Search results for "Image processing"
showing 10 items of 3285 documents
A hardware skin-segmentation IP for vision based smart ADAS through an FPGA prototyping
2017
International audience; In this paper we presents a platform based design approach for fast HW/SW embedded smart Advanced Driver Assistant System (ADAS) design and prototyping. Then, we share our experience in designing and prototyping a HW/SW vision based smart embedded system as an ADAS that helps to increase the safety of car's drivers. We present a physical prototype of the vision ADAS based on a Zynq FPGA. The system detects the fatigue state of the driver by monitoring the eyes closure and generates a real-time alert. A new HW/SW codesign skin segmentation step to locate the eyes/face is proposed. Our presented new approach migrates the skin segmentation step from processing system (S…
Measurement of three-dimensional mirror parameters by polarization imaging applied to catadioptric camera calibration
2008
International audience; We present a new efficient method for calibration of cata- dioptric sensors. The method is based on an accurate measurement of the three-dimensional parameters of the mirror through polariza- tion imaging. While inserting a rotating polarizer between the cam- era and the mirror, the system is automatically calibrated without any calibration patterns. Moreover, this method permits most of the constraints related to the calibration of catadioptric systems to be relaxed. We show that, contrary to our system, the traditional meth- ods of calibration are very sensitive to misalignment of the camera axis and the symmetry axis of the mirror. From the measurement of three-di…
Structure and Chemical Bonds in Black Ti(C, N, O) Thin Films
2010
Design of a customized pattern for improving color constancy across camera and illumination changes
2010
International audience; This paper adresses the problem of color constancy on a large image database acquired with varying digital cameras and lighting conditions. Automatic white balance control proposed by an available commercial camera is not sufficient to provide reproducible color classification. A device-independent color representation may be obtained by applying a chromatic adaptation transform, from a calibrated color checker pattern included in the field of view. Instead of using the standard Macbeth color checker, we suggest to select judicious colors to design a customized pattern from contextual information. A comparative study demonstrates that this approach insures a stronger…
Identification des espèces d'arbres à partir de données T-LiDAR Tree species identification using T-LiDAR data
2013
National audience; En raison de l'utilisation croissante des scanners LiDAR terrestre (T-LiDAR) dans le domaine forestier, le développement d'outils logiciels pour la mesure automatique d'attributs d'inventaire forestier est devenu un domaine de recherche important. De nombreux travaux portant sur la localisation des arbres dans un nuage de points, la mesure du diamètre à hauteur de poitrine (DHP) ou la mesure de la hauteur des arbres ont été décrits dans la littérature. Cependant, le problème de l'identification des espèces d'arbres à partir de données T-LiDAR a été peu abordé. La plupart des travaux utilisent des données LiDAR aéroportées et les espèces des arbres sont déterminées à l'éch…
A gearbox model for processing large volumes of data by using pipeline systems encapsulated into virtual containers
2020
Software pipelines enable organizations to chain applications for adding value to contents (e.g., confidentially, reliability, and integrity) before either sharing them with partners or sending them to the cloud. However, the pipeline components add overhead when processing large volumes of data, which can become critical in real-world scenarios. This paper presents a gearbox model for processing large volumes of data by using pipeline systems encapsulated into virtual containers. In this model, the gears represent applications, whereas gearboxes represent software pipelines. This model was implemented as a collaborative system that automatically performs Gear up (by using parallel patterns…
Shift-Invariant Canonical Polyadic Decomposition of Complex-Valued Multi-Subject fMRI Data with a Phase Sparsity Constraint
2020
Canonical polyadic decomposition (CPD) of multi-subject complex-valued fMRI data can be used to provide spatially and temporally shared components among groups with both magnitude and phase information. However, the CPD model is not well formulated due to the large subject variability in the spatial and temporal modalities, as well as the high noise level in complex-valued fMRI data. Considering that the shift-invariant CPD can model temporal variability across subjects, we propose to further impose a phase sparsity constraint on the shared spatial maps to denoise the complex-valued components and to model the inter-subject spatial variability as well. More precisely, subject-specific time …
Evaluation of the primary stability in dental implants placed in low density bone with a new drilling technique, osseodensification: an in vitro study
2020
Background Primary stability is an important key determinant of implant osseointegration. We investigated approaches to improve primary implant stability using a new drilling technique termed osseodensification (OD), which was compared with the conventional under-drilling (UD) method utilized for low-density bones. Material and Methods We placed 55 conical internal connection implants in each group, in 30 low-density sections of pig tibia. The implants were placed using twist drill bits in both groups; groups Under Drilling (UD) and Osseodensification (OD) included bone sections subjected to conventional UD and OD drilling, respectively. Before placing the implants, we randomized the bone s…
Spatialization of the Semantic Web
2012
syntax for Horn-like rules. The SWRL as the form, antecedentconsequent, where both antecedent and consequent are conjunctions of atoms written a1^ ... ^ an. Atoms in rules can be of the form C(x), P(x,y), Q(x,z), sameAs(x,y), differentFrom(x,y), or builtIn(pred, z1, ..., zn), where C is an OWL description, P is an OWL individual-valued property, Q is an OWL data-valued property, pred is a datatype predicate URIref, x and y are either individual-valued variables or OWL individuals, and z, z1, ... zn are either data-valued variables or OWL data literals. An OWL data literal is either a typed literal or a plain literal. Variables are indicated by using the standard convention of prefixing the…
Cyberbullying in schools : mobile phone and internet effect in adolescents
2017
El objetivo del estudio está enfocado a conocer la prevalencia de las formas de cyberbullying (teléfono móvil e internet) y cómo estas se ven influenciadas por las variables personales y escolares. La muestra final estuvo formada por un total de 749 alumnos de Educación Secundaria Obligatoria, con edades comprendidas entre los 12 y los 15 años (M = 13.77 años; DT = 1.12). Para la recogida de información se utiliza un cuestionario “ad hoc” (datos socioescolares) y la escala de Victimización entre Adolescentes a través del Teléfono Móvil y de Internet (CYBVIC) (Buelga, Cava & Musitu, 2012). De un primer análisis descriptivo, se obtienen porcentajes similares pero con ligera prevalencia en…