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Sparkle and graininess are textural effects that appear as intrinsic spatial features of coatings containing goniochromatic pigments, whereas others such as mottling are undesired outcomes. In this study, we present new methods for the evaluation of sparkle, graininess and mottling of automotive coatings through images acquired with a novel gonio-hyperspectral imaging system based on light-emitting diodes with extended spectral sensitivity beyond the visible range (368&ndash, 1309 nm). A novel analysis of sparkle that considered the amount of sparkling spots was used. Graininess was quantified through a novel statistical descriptor based on the energy descriptor computed from the histogram. A new index was proposed for an enhanced detection of mottling based on the analysis of striping, which was better observed and quantified in the infrared range. Spectral assessments showed a strong relationship with color and spectral reflectance for graininess and mottling. In conclusion, the results showed that these new spatial and spectral methods are a suitable, alternative and potential approach for the assessment of these textural features.

In 2018, a series of experiments were made on the nuclear fusion reactor Weldenstein 7-X. Throughout these experiments, a huge amount of information was generated and gathered. The aim of this work is use image processing knowledge and techniques in order to detect and track some specifics anomalies that can occur inside the reactor. To achieve this goal, the information produced by the infrared cameras will be utilized. En 2018, se realizaron una serie de experimentos en el reactor de fusión nuclear Weldenstein 7-X. A lo largo de estos experimentos, se generó y recopiló una gran cantidad de información. El objetivo de este trabajo es utilizar el conocimiento y las técnicas de procesamiento de imágenes para detectar y rastrear algunas anomalías específicas que pueden ocurrir dentro del reactor. Para lograr este objetivo, será utilizada la información generada por las cámaras infrarrojas. En 2018, es van fer una sèrie d’experiments al reactor de fusió nuclear Weldenstein 7-X . Al llarg d’aquests experiments, es va generar i catalogar una gran quantitat d’informació. L’objectiu d’aquest treball és utilitzar coneixements i tècniques de processament d’imatge per detectar i fer un seguiment d’algunes anomalies específiques que es poden produir dins del reactor. Per aconseguir aquest objectiu, s’utilitzarà la informació generada de les càmeres d’infrarojos.

With the goal of diagnosing skin cancer in an early and noninvasive way, an extended near infrared multispectral imaging system based on an InGaAs sensor with sensitivity from 995 nm to 1613 nm was built to evaluate deeper skin layers thanks to the higher penetration of photons at these wavelengths. The outcomes of this device were combined with those of a previously developed multispectral system that works in the visible and near infrared range (414 nm–995 nm). Both provide spectral and spatial information from skin lesions. A classification method to discriminate between melanomas and nevi was developed based on the analysis of first-order statistics descriptors, principal component analysis, and support vector machine tools. The system provided a sensitivity of 78.6% and a specificity of 84.6%, the latter one being improved with respect to that offered by silicon sensors. This research was supported by the Spanish Ministry of Economy and Competitiveness under the grant DPI2014-56850-R, DPI2017-89414-R, and by the European Union through the project DIAGNOPTICS ‘diagnosis of skin cancer using optics’ (ICT PSP seventh call for proposals 2013).

The aim of this master thesis is to survey the capability of a refractive design to accommodate the requirements of the OUFTI-NEXT payload. The optical design for thermal infrared camera is challenging:• the lack of glass materials in the infrared wavelength limits the optimization• achromatization and athermalization of the lens assembly requires a careful engineeringOn the other hand, a refractive lens system offers a wider field of view with a better compactness than a reflective system. Optical performance such as imaging spatial resolution will be constrained with

Jet fires, often originated by the ignition of hydrocarbon sonic jets, are characterized by a high momentum jet flame lifted from the outlet orifice. The high thermal flux released, especially if there is flames impingement on a given equipment, can lead to a domino effect. Therefore, predicting its size and shape is quite interesting in order to foresee the possibility of this effect on a given equipment. Several mathematical models have been proposed to predict jet fires main features, some of them based on experimental data. However, the analysis of jet flames can be sometimes difficult. In this communication, an inhouse infrared imaging software for jet fire analysis is presented, which allows the calculation of different flamegeometry descriptors. A set of capabilities are included in a graphical user-friendly interface that can help users to easily obtain fire metrics. The tool also provides options to export the results for a post-processing analysis useful for risk prevention, such as preventive design and calculation, and emergency protocols design.

The process of separating small vertebrate fossils from sediment is a monotonous exercise, usually carried out manually and mainly based on morphological features. The large amount of time and personnel required results in the high economic costs associated with this antiquated technique. In this study we test the potential of colour and multispectral imaging for the detection of small vertebrate fossils to facilitate their separation from sediment. This technique is based on the analysis of the spectral and fluorescence characteristics of fossils. Specifically, a multispectral system with a charge-coupled device (CCD) camera attached to a liquid crystal tunable filter and a digital colour camera was used in combination with daylight and ultraviolet light sources. The results show that the reflectance of bones, teeth and sediment are usually different at longer wavelengths, and that fluorescence rates also differ in the bluegreen region. Unfortunately, samples from different paleontological sites present different patterns, hindering the standardization of a method that discriminates microfossils from sediments. However, the combination of colour and multispectral imaging systems with recent advances in laser-stimulated fluorescence in fossils could constitute an optimal solution for an efficient sorting process of small vertebrate remains within geological samples.

In this work, we use a novel multifactor encryption-authentication technique that reinforces optical security by allowing the simultaneous AND-verification of more than one primary image. This optical technique is attractive for high-security purposes that require multifactor reliable authentication. In the example analysed in this work, four reference primary images are scrambled together in the encrypted multifactor distribution. The encrypted multifactor function is distributed in an identification (ID) tag to allow remote readout of the ciphered information. A distortion-invariant ID tag is used so that the verification system is able to detect and identify the information included in the tag even when it is captured rotated or at a varying distance. To make the security system even more reliable, we combine data from visible and near infrared (NIR) specfral bands, without increasing unnecessarily the system complexity. The diversification of sources from which data are gathered adds difficulties to potential attackers. Authentication results are provided to show that the proposed verification system can be an attractive tool for demanding security systems This work has been funded by the Spanish Ministerio de Educacion y Ciencia and FEDER (project DPI2006-05479).

El present treball analitza l'aplicabilitat de diferents tècniques, originalment ideades per al tractament de xàfecs que fan ús d'imatges IR de satèl·lit per estimar la precipitació amb una finalitat climatològica en la nostra regió.S'han estudiat les tècniques d'Arkin, NAW i "Autoestimator" al llarg del període entre juliol de 1994 i juny de 1995, amb una temporalització mensual, estacional i anyal. L'àmbit geogràfic ha estat l'estat espanyol exceptuant les illes Canàries i s'ha treballat com un conjunt o dividit en tres zones, nord i nord-oest, litoral mediterrani i centre i sud de la península. En cada cas s'han aplicat les tècniques originals a les imatges METEOSAT corresponents (24 o 48 diàries, depenent de la tècnica), i s'han estudiat i aplicat aquelles modificacions que proporcionaven millors resultats en la regió analitzada.Les principals conclusions a que s'ha arribat són les següents:· La utilització de tècniques de determinació de precipitació a partir d'imatges IR de satèl·lit presenta avantatges (extensió territorial i temporal) front tècniques basades en observacions en terra. El fet que la determinació de la precipitació en una imatge IR es faci de manera indirecta, obliga a calibrar aquestes tècniques per a cada zona geogràfica.Tècnica d'Arkin:· De les tècniques analitzades la d'Arkin és la més simple i ràpida d'aplicar. Els valors originals de temperatura llindar i intensitat de precipitació no s'adapten a la nostra zona geogràfica. Una temperatura llindar més elevada (255 o 260 K) amb una intensitat de precipitació menor ( 0.5 o 0.4 mm/h) s'adequa més.· En general la tècnica proporciona pobres correlacions per als mesos d'hivern, sent més altes en els mesos de tardor i estiu.Tècnica NAW:· La tècnica NAW original millora lleugerament la correlació respecte la tècnica d'Arkin, però sobreestima fortament la precipitació. Assignacions de precipitació menors que les originals són necessàries per eliminar les sobreestimacions del mètode.· L'aplicació de discriminants per increment de temperatura no millora les correlacions excepte en el litoral mediterrani.· Els mesos de tardor i estiu presenten les millors correlacions, i els d'hivern les pitjors.Tècnica "Autoestimator":· La tècnica "Autoestimator" no millora, en general els resultats de les tècniques d'Arkin i NAW. L'equació original sobreestima la precipitació en gairebé tots els mesos. Les modificacions introduïdes en l'equació original milloren les correlacions disminuint les sobreestimacions del mètode. Cal una calibració de la tècnica per a cada zona concreta i per a cada estació particular si es vol que la tècnica presenti estimacions fiables de la precipitació.Comparació de les tres tècniques:· Les tres tècniques tenen moltes dificultats en separar els núvols que aporten precipitació d'aquells que no en porten. Aquest fet pot explicar les baixes correlacions en mesos amb poca precipitació però en què les imatges mostren la presència abundant de núvols.· En el conjunt de l'any la tècnica NAW té la correlació més alta seguida de molt a prop per la d'Arkin. NAW és la que sobreestima més i Arkin la que menys. Per mesos Arkin sembla seguir millor les variacions, estimant correctament la precipitació en els mesos de tardor. La tècnica "Autoestimator" sembla reflectir millor la precipitació per episodis concrets.· Les estimacions de totes les tècniques millorarien si es tingués en compte la quantitat de vapor d'aigua present en l'atmosfera., The aim of this work is to analyse the ability of different techniques, based on infrared satellite images and used in the study of heavy rainfall, to estimate the rainfall in our area for climatic purposes. The Arkin, NAW and Autoestimator techniques are applied during the period July 1994-June 1995, using different temporal steps (month, seasonal and annual). The studies have been applied to Spain, excluding Canary Islands. This area was divided in three sub-areas: north and north-west, Mediterranean coast, and centre and south of the peninsula. The three areas were processed together or individually. The original techniques were applied to the METEOSAT images (24 or 48 per day). We studied different improvements of the techniques and applied systematically the best for our climatic area. The main conclusions achieved are:· The use of techniques to determine the rainfall using IR satellite images is the more suitable than techniques based on land observations. These methods must be calibrated for every geographic area because the rainfall determination using the IR images is an indirect method.Arkin technique:· The Arkin the simplest and easiest technique to be applied. The original values of threshold temperature and rainrate are not suitable to the geographic area studied. A higher threshold temperature (255 o 260 K) joined to a smaller rainrate (0.5-0.4 mm/h) fit better results.· Generally, the technique gives poor correlation for the winter months, and higher correlation for the autumn and summer months.NAW technique:· The original NAW technique gives a little better correlation than the Arkin technique, but NAW shows some important rainfall overestimates. To remove the overestimates of the method lower rainrates than the original ones must be set.· Empirical discriminations based on temperature difference into a cloud don't improve the correlation except for the Mediterranean area.· Autumn and summer months show the best correlations, and the winter ones the worst.Autoestimator technique:· In general, the Autoestimator technique doesn't improve the Arkin and NAW results. The original equation overestimates almost months. The modifications included give better correlations, decreasing the overestimates of the method.· For every single area and station the techniques must be calibrated if reliable rainfall estimates are desirable.Comparison of the techniques:· All techniques used have a lot of difficulties to discriminate the clouds that give or don't give rainfall. This could be the reason for the low correlations for months with low rainfall but IR images that shows a lot of clouds.· For the whole year NAW technique has the best correlation, similar to Arkin method. NAW gives the most overestimates and Arkin shows the lowest overestimates. Arkin defines better the variations by months, fitting the rainfall properly for the autumn months. The Autoestimator technique shows better results for particular episode. · The estimates for all methods will improve if the water vapour present in the atmosphere is taken into account.

With the goal of diagnosing skin cancer in an early and noninvasive way, an extended near infrared multispectral imaging system based on an InGaAs sensor with sensitivity from 995 nm to 1613 nm was built to evaluate deeper skin layers thanks to the higher penetration of photons at these wavelengths. The outcomes of this device were combined with those of a previously developed multispectral system that works in the visible and near infrared range (414 nm–995 nm). Both provide spectral and spatial information from skin lesions. A classification method to discriminate between melanomas and nevi was developed based on the analysis of first-order statistics descriptors, principal component analysis, and support vector machine tools. The system provided a sensitivity of 78.6% and a specificity of 84.6%, the latter one being improved with respect to that offered by silicon sensors.