Дисертації з теми "Évaluation de la qualité d'image"
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Souidène, Wided. "Exploitation de la diversité informationnelle en restauration autodidacte et évaluation de qualité." Paris 13, 2007. http://www.theses.fr/2007PA132015.
Повний текст джерелаMambo, Shadrack. "Optimisation et évaluation des performance en traitement d'image." Thesis, Paris Est, 2018. http://www.theses.fr/2018PESC1125/document.
Повний текст джерелаD’Tech Thesis SummaryThe importance of medical imaging as a core component of several medical application and healthcare diagnosis cannot be over emphasised. Integration of useful data acquired from different images is vital for proper analysis of information contained in the images under observation. For the integration process to be successful, a procedure referred to as image registration is necessary.The purpose of image registration is to align two images in order to find a geometric transformation that brings one image into the best possible spatial correspondence with another image by optimising a registration criterion. The two images are known as the target image and the source image. Image registration methods consist of having the two images referenced with control points. This is followed by a registration transformation that relates the two images and a similarity metric function that aims to measure the qualitative value of closeness or degree of fitness between the target image and the source image. Finally, an optimiser which seeks an optimal transformation inside the defined solution search space is performed.This research presents an automated image registration algorithm for solving multimodal image registration on lung Computer Tomography (CT) scan pairs, where a comparison between regular step gradient descent optimisation technique and evolutionary optimisation was investigated. The aim of this research is to carry out optimisation and performance evaluation of image registration techniques in order to provide medical specialists with estimation on how accurate and robust the registration process is. Lung CT scan pairs are registered using mutual information as a similarity measure, affine transformation and linear interpolation. In order to minimise the cost function, an optimiser, which seeks the optimal transformation inside the defined search space is applied.Determination of a transformation model that depends on transformation parameters and identification of similarity metric based on voxel intensity were carried out. By fitting transformation to control points, three transformation models were compared. Affine transformation produced the best recovered image when compared to non-reflective similarity and projective transformations. The results of this research compares well with documented results from EMPIRE 10 Challenge research and conforms to both theoretical principles as well as practical applications.The contribution of this research is its potential to increase the scientific understanding of image registration of anatomical body organs. It lays a basis for further research in performance evaluation of registration techniques and validation of procedures to other types of algorithms and image registration application areas, such as remote sensing, satellite communication, biomedical engineering, robotics, geographical information systems and mapping, among others
Yang, Yanqin. "Contribution à l'évaluation objective de la qualité d'images couleur estimées par dématriçage." Thesis, Lille 1, 2009. http://www.theses.fr/2009LIL10089/document.
Повний текст джерелаOur work deals with the quality of colour images provided by a mono-CCD colour camera, which acquires only one colour component at each pixel by means of the CFA (Colour Filter Array) which covers the CCD sensor. A procedure - called demosaicing - is necessary to estimate the other two missing colour components at each pixel, so as to obtain a colour image in this kind of cameras. We aim to determine which method of demosaicing provides the results that are best adapted to colour image analyses for the reconstruction of scene. First, we present the principles on how the mono-CCD cameras acquire digital colour images, as well as the different arrangements of CFA used in such cameras. Once the influence of the CFA arrangement on the performance of demosaicing has been presented, we focus our studies on the demosaicing methods based on the Bayer CFA. A mathematical formalization for demosaicing is proposed before we present the numerous demosaicing methods in the literature, as well as the post-processing algorithms to correct the demosaiced images. We then investigate the evaluation criteria for the quality of the colour images estimated by demosaicing. First are described the different possible artefacts generated by demosaicing and the reasons for their generation, which allow us to point out the limits of the classical measures used to evaluate the estimated images. We then propose two original measures to quantify the presence of the two main artefacts, namely false colour and zipper effect. At last, we present new criteria based on the analysis of features extracted from colour images, by measuring the quality of edge detection in the estimated images
Cherifi, Daikha. "Amélioration et évaluation de la qualité des images." Thesis, Paris 13, 2014. http://www.theses.fr/2014PA132053.
Повний текст джерелаThe aim of this thesis is to propose new methods for image enhancement based on oriented and multi-scale transforms using some perceptual criteria. The first part of the thesis is devoted to the development of a simple and efficient contrast enhancement method inspired from the human visual system. This method is evaluated on a set of natural color and monochrome images. The obtained results are evaluated subjectively and by using objective measures based on energy spectrum analysis and perceptual criteria. The enhancement technique is also extended to some medical images, such as mammography and endoscopy images. A special contrast enhancement method adapted to mammography is then proposed. It is based on a segmentation process using a priori information on the mammography images. The last part of the thesis is devoted to image enhancement evaluation. A critical literature survey of image enhancement evaluation methods is provided. The evaluation method proposed in this thesis is based on the radial and angular analysis of the Fourier powerspectrum. Another perceptual approach is proposed to evaluate the output. This method is based on the analysis of the visibility map computed by using a pyramidal contrast. The evaluation is performed on some samples taken from two databases. Both subjective and objective evaluations demonstrate the efficiency of the proposed image enhancement methods
Hachicha, Walid. "Traitement, codage et évaluation de la qualité d’images stéréoscopiques." Thesis, Paris 13, 2014. http://www.theses.fr/2014PA132037.
Повний текст джерелаRecent developments in 3D stereoscopic technology have opened new horizons in many application fields such as 3DTV, 3D cinema, video games and videoconferencing and at the same time raised a number of challenges related to the processing and coding of 3D data. Today, stereoscopic imaging technology is becoming widely used in many fields. There are still some problems related to the physical limitations of image acquisition systems, e.g. transmission and storage requirements. The objective of this thesis is the development of methods for improving the main steps of stereoscopic imaging pipeline such as enhancement, coding and quality assessment. The first part of this work addresses quality issues including contrast enhancement and quality assessment of stereoscopic images. Three algorithms have been proposed. The first algorithm deals with the contrast enhancement aiming at promoting the local contrast guided by calculated/estimated object importance map in the visual scene. The second and the third algorithms aim at predicting the distortion severity of stereo images. In the second one, we have proposed a fullreference metric that requires the reference image and is based on some 2D and 3D findings such as amplitude non-linearity, contrast sensitivity, frequency and directional selectivity, and binocular just noticeable difference model. While in the third algorithm, we have proposed a no-reference metric which needs only the stereo pair to predict its quality. The latter is based on Natural Scene statistics to identify the distortion affecting the stereo image. The statistic 3D features consist in combining features extracted from the natural stereo pair and those from the estimate disparity map. To this end, a joint wavelet transform, inspired from the vector lifting concept is first employed. Then, the features are extracted from the obtained subbands. The second part of this dissertation addresses stereoscopic image compression issues. We started by investigating a one-dimensional directional discrete cosine transform to encode the disparity compensated residual image. Afterwards, and based on the wavelet transform, we investigated two techniques for optimizing the computation of the residual image. Finally, we present efficient bit allocation methods for stereo image coding purpose. Generally, the bit allocation problem is solved in an empirical manner by looking for the optimal rates leading to the minimum distortion value. Thanks to recently published work on approximations of the entropy and distortion functions, we proposed accurate and fast bit allocation schemes appropriate for the open-loop and closed-loop based stereo coding structures
Beretta, Patricia. "Compression d'images appliquée aux angiographies cardiaques : aspects algorithmiques, évaluation de la qualité diagnostique." Lyon, INSA, 1997. http://theses.insa-lyon.fr/publication/1997ISAL0107/these.pdf.
Повний текст джерелаQuintard, Ludovic. "Evaluation de la qualité des dispositifs d'affichage couleur : des évaluations subjectives à la mesure objective." Poitiers, 2008. http://theses.edel.univ-poitiers.fr/theses/2008/Quintard-Ludovic/2008-Quintard-Ludovic-These.pdf.
Повний текст джерелаThis thesis was conducted in cooperation with the Laboratoire National de Métrologie et d’Essais (LNE) within the framework of a CIFRE convention. This work consisted in realising an objective metric dedicated to the assessment of image retrieval devices (screens). To address the underlying issues, we developed an algorithm for estimating quality using the monitor features and those of the Human Visual System. The developed algorithm is made up of three blocks. The first block takes into account the technical features of the monitor (transfer function, gamut, etc. ) to turn a digital image (sent to the monitor using a digital device) into a physical image (displayed by the monitor). The second block of the algorithm models the transformation of the physical image into a perceptual image. This modelling involves familiarity with human visual system operational principles, particularly the encoding of colour information, as well as the perceptual attributes involved in judging a colour digital image quality. The required knowledge is described in chapter 4 of the present thesis. The third and last block was developed to rate the quality of this perceptual image. A subjective study of the quality of 5 different LCD screens involving thirty participants and based on six analysis criteria was performed. It successfully showed that colour, saturation and contrast are major factors on which the screen quality is assessed. The metric developed was based on these findings and shows good correlation with subjective evaluation data, thus showing similarity with human judgement. The metric was also tested in the field of JPEG and JPEG2000 compression with similar efficiency
Zhang-Ge, Lu. "Modèles numériques pour l'évaluation objective de la qualité d'images médicales." Angers, 2012. http://tel.archives-ouvertes.fr/tel-00995416.
Повний текст джерелаMedical image quality assessment is critical for comparing and optimizing medical imaging system. In the frame of task-based approach, numerical observers proposed for the objective medical image quality assessment have several limitations: e. G. For the multi-signal localization, most need a priori knowledge of signal parameters; multi-slice MOs narrow the task down to the detection of one symmetrical signal at the image centre. In this thesis, we propose novel numerical observers: the CJO for the detection of one parametric signal with random amplitude, orientation and size on single-slice; the PCJO and the msPCJO for the detection-localization of multiple parametric signals with random amplitude, orientation, size and location on single-slice and multi-slice, respectively. Two observer studies were designed and implemented for their validation on MR images with MS lesions, and the JAFROC FOM results indicate that they are promising for predicting radiologists' task performance, ultimately for evaluating medical imaging systems
Khan, Muhammad Murtaza. "Fusion d'images multispectrale, hyperspectrale et panchromatique de résolutions spatiales différentes et évaluation de la qualité en télédétection satellitaire." Grenoble INPG, 2009. http://www.theses.fr/2009INPG0090.
Повний текст джерелаFusion or Pansharpening improves the spatial quality of Multispectral satellite images by making use of details present in a high resolution Panchromatic image. The different nature of Panchromatic and Multispectral sensors requires that the details are added using a detail injection model. Most of the available detail injection model parameters are estimated at degraded resolution and then interpolated for use at the higher resolution. In this work we have presented a detail injection model which estimates the detail injection parameters directly at the desired higher resolution. The model optimizes the ”Quality Not Requiring a Reference index”. The proposed method is then extended for pansharpening of Hyperspectral images. Finally, a quality assessment index, not requiring a high resolution reference, is proposed for determining the quality of pansharpened images at full resolution. The novelty of the method lies in the use of sensors ”Modulation Transfer Function” filters for separating the low and high frequency information for determining the spectral and spatial distortions, respectively
Zhang, Lu. "Modèles Numériques pour l'Évaluation Objective de la Qualité d'Images Médicales." Phd thesis, Université d'Angers, 2012. http://tel.archives-ouvertes.fr/tel-00782522.
Повний текст джерелаZhangh-Ge, Lu. "Modèles Numériques pour l'Évaluation Objective de la Qualité d'Images Médicales." Phd thesis, Université d'Angers, 2012. http://tel.archives-ouvertes.fr/tel-00995416.
Повний текст джерелаSendjasni, Abderrezzaq. "Objective and subjective quality assessment of 360-degree images." Electronic Thesis or Diss., Poitiers, 2023. http://www.theses.fr/2023POIT2251.
Повний текст джерела360-degree images, a.k.a. omnidirectional images, are in the center of immersive media. With the increase in demands of the latter, mainly thanks to the offered interactive and immersive experience, it is paramount to provide good quality of experience (QoE). This QoE is significantly impacted by the quality of the content. Like any type of visual signal, 360-degree images go through a sequence of processes including encoding, transmission, decoding, and rendering. Each of these processes has the potential to introduce distortions to the content. To improve the QoE, image quality assessment (IQA) is one of the strategies to be followed. This thesis addresses the quality evaluation of 360-degree images from the objective and subjective perspectives. By focusing on the influence of Head Mounted Displays (HMDs) on the perceived quality of 360-degree images, a psycho-visual study is designed and carried out using four different devices. For this purpose, a 360-degree image datasets is created and a panel of observers is involved. The impact of HMDs on the quality ratings is identified and highlighted as an important factor to consider when con- ducting subjective experiments for 360-degree images. From the objective perspective, we first comprehensively benchmarked several convolutional neural network (CNN) models under various configurations. Then, the processing chain of CNN-based 360-IQA is improved at different scales, from input sampling and representation to aggregating quality scores. Based on the observations of the above studies as well as the benchmark, two 360-IQA models based on CNNs are proposed to accurately predict the quality of 360-degree images. The obtained observations and conclusions from the various contributions shall bring insights for assessing the quality of 360-degree images
360-graders bilder, også kjent som rundstrålende bilder, er i sentrum av oppslukende medier. Med økningen i forventninger til sistnevnte, hovedsakelig takket være den aktiverte interaktive og oppslukende opplevelse, er det avgjørende å gi god kvaliteten på opplevelsen (QoE).Denne QoE er betydelig påvirket av kvaliteten på innholdet. Som alle typer visuelle signaler går 360-graders bilder gjennom en sekvens av prosesser, inkludert koding, overføring, dekoding og gjengivelse. Hver av disse prosessene har potensial til å introdusere forvrengninger til innholdet.For å forbedre QoE er vurdering av bildekvalitet (IQA) en av strategiene å følge. Denne oppgaven tar for seg kvalitetsevaluering av 360-graders bilder fra objektive og subjektive perspektiver. Ved å fokusere på påvirkningen av Head Mounted Displays (HMD-er) på den oppfattede kvaliteten til 360-graders bilder, er en psyko-visuell studie designet og utført ved hjelp av fire forskjellige enheter. For dette formålet opprettes et 360-graders bildedatasett og et panel av observatører er involvert. Virkningen av HMD-er på valitetsvurderingene identifiseres og fremheves som en viktig faktor når du utfører subjektive eksperimenter for 360-graders bilder.Fra det objektive perspektivet benchmarket vi først flere konvolusjonelle nevrale nettverk (CNN) under forskjellige konfigurasjoner. Deretter forbedres prosesseringskjeden til CNN-baserte 360-IQA i forskjellige skalaer, fra input-sampling og representasjon til aggregering av kvalitetspoeng. Basert på observasjonene av de ovenfornevnte studiene så vel som benchmark, foreslås to 360-IQA-modeller basert på CNN-er for å nøyaktig forutsi kvaliteten på 360-graders bilder.De innhentede observasjonene og konklusjonene fra de ulike bidragene skal gi innsikt for å vurdere kvaliteten på 360-graders bilder
Ouni, Sonia. "Evaluation de la qualité des images couleur. Application à la recherche & à l'amélioration des images." Thesis, Reims, 2012. http://www.theses.fr/2012REIMS034.
Повний текст джерелаThe research area in the objective quality assessment of the color images has been a renewed interest in recent years. The work is primarily driven by the advent of digital pictures and additional needs in image coding (compression, transmission, recovery, indexing,...). So far the best evaluation is visual (hence subjective) or by psychophysical techniques or by expert evaluation. Therefore, it is useful, even necessary, to establish criteria and objectives that automatically measures quality scores closest possible quality scores given by the subjective evaluation. We propose, firstly, a new full reference metric to assess the quality of color images, called overall Delta E, based on color appearance and incorporates the features of the human visual system (HVS). Performance was measured in two areas of application compression and restoration. The experiments carried out show a significant correlation between the results and subjective assessment.Then, we propose a new no reference quality assessmenent color images approach based on neural networks: given the multidimensional nature of image quality, a quantification of quality has been proposed, based on a set of attributes forming the descriptor UN (Utility, Naturalness). Accuracy reflects the sharpness and clarity. As for naturality, it reflects the brightness and color. To model the criterion of color, three no reference metrics were defined to detect the dominant color in the image, the proportion of that color and its spatial dispersion. This approach is based on neural networks to mimic the HVS perception. Two variants of this approach have been tried (direct and progressive). The results showed the performance of the progressive variant compared to the direct variant. The application of the proposed approach in two areas: in the context of restoration, this approach has served as a stopping criterion for automatic restoration algorithms. In addition, we have used in a system for estimating the quality of images to automatically detect the type of content in an image degradation. In the context of indexing and image retrieval, the proposed approach was used to introduce the quality of images in the database as an index. The experimental results showed the improvement of system performance image search by content by using the index or by making a quality refinement results with the quality criterion
Randrianasoa, Tianatahina Jimmy Francky. "Représentation d'images hiérarchique multi-critère." Thesis, Reims, 2017. http://www.theses.fr/2017REIMS040/document.
Повний текст джерелаSegmentation is a crucial task in image analysis. Novel acquisition devices bring new images with higher resolutions, containing more heterogeneous objects. It becomes also easier to get many images of an area from different sources. This phenomenon is encountered in many domains (e.g. remote sensing, medical imaging) making difficult the use of classical image segmentation methods. Hierarchical segmentation approaches provide solutions to such issues. Particularly, the Binary Partition Tree (BPT) is a hierarchical data-structure modeling an image content at different scales. It is built in a mono-feature way (i.e. one image, one metric) by merging progressively similar connected regions. However, the metric has to be carefully thought by the user and the handling of several images is generally dealt with by gathering multiple information provided by various spectral bands into a single metric. Our first contribution is a generalized framework for the BPT construction in a multi-feature way. It relies on a strategy setting up a consensus between many metrics, allowing us to obtain a unified hierarchical segmentation space. Surprisingly, few works were devoted to the evaluation of hierarchical structures. Our second contribution is a framework for evaluating the quality of BPTs relying both on intrinsic and extrinsic quality analysis based on ground-truth examples. We also discuss about the use of this evaluation framework both for evaluating the quality of a given BPT and for determining which BPT should be built for a given application. Experiments using satellite images emphasize the relevance of the proposed frameworks in the context of image segmentation
Liu, Xinwei. "Multi-modality quality assessment for unconstrained biometric samples." Thesis, Normandie, 2018. http://www.theses.fr/2018NORMC284/document.
Повний текст джерелаThe aim of this research is to investigate multi-modality biometric image qualityassessment methods for unconstrained samples. Studies of biometrics noted thesignificance of sample quality for a recognition system or a comparison algorithmbecause the performance of the biometric system depends mainly on the qualityof the sample images. The need to assess the quality of multi-modality biometricsamples is increased with the requirement of a high accuracy multi-modalitybiometric systems.Following an introduction and background in biometrics and biometric samplequality, we introduce the concept of biometric sample quality assessment for multiplemodalities. Recently established ISO/IEC quality standards for fingerprint,iris, and face are presented. In addition, sample quality assessment approacheswhich are designed specific for contact-based and contactless fingerprint, nearinfrared-based iris and visible wavelength iris, as well as face are surveyed. Followingthe survey, approaches for the performance evaluation of biometric samplequality assessment methods are also investigated.Based on the knowledge gathered from the biometric sample quality assessmentchallenges, we propose a common framework for the assessment of multi-modalitybiometric image quality. We review the previous classification of image-basedquality attributes for a single biometric modality and investigate what are the commonimage-based attributes for multi-modality. Then we select and re-define themost important image-based quality attributes for the common framework. In order to link these quality attributes to the real biometric samples, we develop anew multi-modality biometric image quality database which has both high qualitysample images and degraded images for contactless fingerprint, visible wavelengthiris, and face modalities. The degradation types are based on the selected commonimage-based quality attributes. Another important aspect in the proposed commonframework is the image quality metrics and their applications in biometrics. Wefirst introduce and classify the existing image quality metrics and then conducteda brief survey of no-reference image quality metrics, which can be applied to biometricsample quality assessment. Plus, we investigate how no-reference imagequality metrics have been used for the quality assessment for fingerprint, iris, andface biometric modalities.The experiments for the performance evaluation of no-reference image qualitymetrics for visible wavelength face and iris modalities are conducted. The experimentalresults indicate that there are several no-reference image quality metricsthat can assess the quality of both iris and face biometric samples. Lastly, we optimizethe best metric by re-training it. The re-trained image quality metric canprovide better recognition performance than the original. Through the work carriedout in this thesis we have shown the applicability of no-reference image qualitymetrics for the assessment of unconstrained multi-modality biometric samples
Rousselot, Maxime. "Image quality assessment of High Dynamic Range and Wide Color Gamut images." Thesis, Rennes 1, 2019. http://www.theses.fr/2019REN1S034/document.
Повний текст джерелаTo improve their ability to display astonishing images, screen technologies have been greatly evolving. For example, the contrast of high dynamic range rendering systems far exceed the capacity of a conventional display. Moreover, a Wide Color gamut display can cover a bigger color space than ever. Assessing the quality of these new content has become an active field of research as classical SDR quality metrics are not adapted. However, state-of-the-art studies often neglect one important image characteristics: chrominances. Indeed, previous databases contain HDR images with a standard gamut thus neglecting the increase of color space due to WCG. Due to their gamut, these databases are less prone to contain chromatic artifacts than WCG content. Moreover, most existing HDR objective quality metrics only consider luminance and are not considering chromatic artifacts. To overcome this problematic, in this thesis, we have created two HDR / WCG databases with annotated subjective scores. We focus on the creation of a realistic chromatic artifacts that can arise during compression. In addition, using these databases, we explore three solutions to create HDR / WCG metrics. First, we propose a method to adapt SDR metrics to HDR / WCG content. Then, we proposed an extension of a well-known HDR metric called HDR-VDP-2. Finally, we create a new metric based on the merger of various quality metric and color features. This last metric presents very good performance to predict quality while being sensitive to chromatic distortion
Thomas, Claire. "Fusion d'images de résolutions spatiales différentes." Phd thesis, École Nationale Supérieure des Mines de Paris, 2006. http://pastel.archives-ouvertes.fr/pastel-00002097.
Повний текст джерелаKang, Chen. "Image Aesthetic Quality Assessment Based on Deep Neural Networks." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASG004.
Повний текст джерелаWith the development of capture devices and the Internet, people access to an increasing amount of images. Assessing visual aesthetics has important applications in several domains, from image retrieval and recommendation to enhancement. Image aesthetic quality assessment aims at determining how beautiful an image looks to human observers. Many problems in this field are not studied well, including the subjectivity of aesthetic quality assessment, explanation of aesthetics and the human-annotated data collection. Conventional image aesthetic quality prediction aims at predicting the average score or aesthetic class of a picture. However, the aesthetic prediction is intrinsically subjective, and images with similar mean aesthetic scores/class might display very different levels of consensus by human raters. Recent work has dealt with aesthetic subjectivity by predicting the distribution of human scores, but predicting the distribution is not directly interpretable in terms of subjectivity, and might be sub-optimal compared to directly estimating subjectivity descriptors computed from ground-truth scores. Furthermore, labels in existing datasets are often noisy, incomplete or they do not allow more sophisticated tasks such as understanding why an image looks beautiful or not to a human observer. In this thesis, we first propose several measures of subjectivity, ranging from simple statistical measures such as the standard deviation of the scores, to newly proposed descriptors inspired by information theory. We evaluate the prediction performance of these measures when they are computed from predicted score distributions and when they are directly learned from ground-truth data. We find that the latter strategy provides in general better results. We also use the subjectivity to improve predicting aesthetic scores, showing that information theory inspired subjectivity measures perform better than statistical measures. Then, we propose an Explainable Visual Aesthetics (EVA) dataset, which contains 4070 images with at least 30 votes per image. EVA has been crowd-sourced using a more disciplined approach inspired by quality assessment best practices. It also offers additional features, such as the degree of difficulty in assessing the aesthetic score, rating for 4 complementary aesthetic attributes, as well as the relative importance of each attribute to form aesthetic opinions. The publicly available dataset is expected to contribute to future research on understanding and predicting visual quality aesthetics. Additionally, we studied the explainability of image aesthetic quality assessment. A statistical analysis on EVA demonstrates that the collected attributes and relative importance can be linearly combined to explain effectively the overall aesthetic mean opinion scores. We found subjectivity has a limited correlation to average personal difficulty in aesthetic assessment, and the subject's region, photographic level and age affect the user's aesthetic assessment significantly
Fan, Yu. "Quality assessment of stereoscopic 3D content based on binocular perception." Thesis, Poitiers, 2019. http://www.theses.fr/2019POIT2266.
Повний текст джерелаThe great advance of stereoscopic/3D technologies leads to a remarkable growth of 3D content in various applications thanks to a realistic and immersive experience. However, these technologies also brought some technical challenges and issues, regarding quality assessment and compression due to the complex processes of the binocular vision. Aiming to evaluate and optimize the performance of 3D imaging systems with respect to their storage capacity and quality of experience (QoE), this thesis focuses on two main parts: 1- spatial visibility thresholds of the human visual system (HVS) and 2- stereoscopic image quality assessment (SIQA). It is well-known that the HVS cannot detect the changes in a compressed image if these changes are lower than the just noticeable different (JND) threshold. Therefore, an extensive study based on objective and subjective analysis has been conducted on existing 3D-JND models. In addition, a new 3D-JND model has been proposed based on psychophysical experiments aiming to measure the effect of binocular disparity and spatial masking on the visual thresholds. In the second part, we explored new approaches for SIQA from two different perspectives. First, we developed a reference-based model accounting for both monocular and cyclopean quality. Then, we proposed a new blind quality metric relying on local contrast statistics combination of the stereopair. Both models considered the binocular fusion and binocular rivalry behaviors of the HVS in order to accurately simulate the human judgment of 3D quality
Dragović-Drouet, Mila. "Évaluation de la qualité des traductions éditoriales." Paris 3, 2003. http://www.theses.fr/2003PA030049.
Повний текст джерелаThe present thesis aims to define quality assessment criteria for professionally translated published works, based on the interpretive theory of translation (Paris school). The theoretical assumption is that the translation process and the assessment of its results must be viewed holistically as part of a single communicative act encompassing the roles, competences and objectives of all those involved. The revising and the reviewing of published translated works are observed in the light of the fact that published translations stand alongside "native language" works and must therefore be able to stand alone as texts in their own right, the reference to the original being inevitable only in fine. A corpus of translated works is assessed and used to demonstrate that the effective quality assessment of published translations requires at least some knowledge of the translation process and of the translator's specific skills
Chetouani, Aladine. "Vers un système d'évaluation de la qualité d'image multi-critères." Phd thesis, Université Paris-Nord - Paris XIII, 2010. http://tel.archives-ouvertes.fr/tel-00560808.
Повний текст джерелаLe, Quyet Tien. "Vers une analyse et une compréhension de la qualité d'image." Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALT060.
Повний текст джерелаIn this thesis, the main contributions are to study 2 main aspects of image quality including image aesthetic, image naturalness and the relations between the 2 concepts. More specifically, image aesthetic is the measure of how aesthetically a photo fulfills the observer’s expectation while the image naturalness definition is both related to artifacts induced by some image processing algorithms and to the individual feeling about how a picture matches with image memory. On the side of image aesthetic, the thesis deals with the problem of evaluating the roles of pre-processing operations in image aesthetic assessment. Image aesthetic assessment models based on prior image segmentation (region of interest extraction) and prior image classification (large field / close-up image classification) have been developed and compared with image aesthetic assessment models without pre-processing stages. At the same time different models base either on handcrafted features or learned features have been studied for the purpose of image aesthetic estimation. Based on the obtained results, an image aesthetic assessment model based on image classification and region segmentation has been introduced and evaluated. On the side of image naturalness, image naturalness of standard dynamic range images, especially tone-mapped images have been studied with both subjective and objective methodologies. A subjective experiment has been organized to collect human evaluations about image naturalness first. Then, various objective algorithms have been validated on the collected subjective data for the image naturalness assessment task. This work focuses on the problem of developing a model firstly to estimate if an image looks natural or not to humans and the second purpose is to try to understand how the unnaturalness feeling is induced by a photo: "Are there specific unnaturalness clues or is unnaturalness a general feeling when looking at a photo?". Finally, the relations between the 2 aspects: image aesthetic and image naturalness have been evaluated and discussed
Hassani, El Arbi. "Qualité en recherche : proposition pour une évolution conjointe des processus qualité et recherche." Paris, ENSAM, 2007. http://www.theses.fr/2007ENAM0016.
Повний текст джерелаThe development of a quality management approach has undergone a revolution so much on the normative level as on the level of implementation of elaborated standards these last ten years. This revolution was marked by the fast increase in the number of enterprises' certification as well as testing and calibration laboratories. The Quality management approach has contributed to the improvement of this type of so-called repetitive or routine processes. Research processes have been little involved by this quality management approach. Given the evolution of international relations, new stakes of scientific, economic, societal and environmental nature have appeared. The inventory of fixtures of the works and reflections concerning quality in research show that the researcher's culture does not permit to apply quality management in the same way as for routine industrial and service activities. To set up of quality management approach in research, we have defined five general principles which enable us to elaborate a guide for its deployment adapted to the activities of research
Rabeux, Vincent. "Évaluation de la qualité des documents anciens numérisés." Phd thesis, Université Sciences et Technologies - Bordeaux I, 2013. http://tel.archives-ouvertes.fr/tel-00858290.
Повний текст джерелаBondiau, Pierre-Yves. "Mise en œuvre et évaluation d'outils de fusion d'image en radiothérapie." Phd thesis, Université de Nice Sophia-Antipolis, 2004. http://tel.archives-ouvertes.fr/tel-00327972.
Повний текст джерелаNous effectuerons une mise au point sur le recalage d'images, les différentes techniques sont passées en revue dans le but d'être didactique vis-à-vis de la communauté médicale. Les résultats du recalage sont présentés dans le cadre de la planification de la radiothérapie cérébrale et prostatique afin de préciser les types de recalage applicables en oncologie et plus particulièrement à la radiothérapie.
Ensuite, nous présentons les perspectives de ce type d'application selon différentes régions anatomiques. Les applications de la segmentation automatiques et l'évaluation des résultats dans le cadre des tumeur de l'encéphale sont décrits après avoir passé en revue les différentes méthodes de segmentation utilisables selon les localisations anatomiques.
Nous verrons une application originale : la simulation numérique de la croissance tumorale virtuelle et la comparaison avec la croissance réelle d'une tumeur cérébrale présentée par un patient.
Enfin, nous exposerons les futurs développements possibles des outils de traitement de l'image en radiothérapie ainsi que les pistes des recherche à explorer en oncologie.
Bondiau, Pierre-Yves. "Mise en oeuvre et évaluation d'outils de fusion d'image en radiothérapie." Nice, 2004. http://www.theses.fr/2004NICE4114.
Повний текст джерелаCancer is a major problem of public health. Treatment can be done in a general or loco-regional way, in which case medical images are important as they specify the localization of the tumour. The objective of the radiotherapy is to deliver a curative dose of radiation in the target volume while sparing the organs at risks (OAR). The determination of the accurate localization of the targets volume as well as OAF makes it possible to define the ballistics of irradiation beams. After the description of the principles of radiotherapy and cancers treatment, we specify the clinical stakes of ocular, cerebral and prostatic tumours. We review the state of the art image matching algorithms, with a didactic purpose for the medical community. The results of image matching techniques are presented in the framework of cerebral and prostatic radiotherapy planning in order to determine the types of applicable method in oncology. Then, we present the prospects for these methods with respect to the anatomical localization and automatic segmentation. Applications of automatic segmentation and the evaluation of the results in the framework of brain tumour are described after a review of the various segmentation methods according to anatomical localizations. An original application is the digital simulation of the virtual tumoral growth and the comparison with the real growth of a cerebral tumour presented by a patient. We conclude with the future developments possible of the tools for image processing in radiotherapy as well as the tracks of research to be explored in oncology
Manita, Riadh. "Comité d'audit et qualité de l'audit externe : vers le développement d'un outil d'évaluation de la qualité du processus d'audit." Besançon, 2005. http://www.theses.fr/2005BESAA011.
Повний текст джерелаThe recent financial scandals that shaked the financial and audit markets led to debates in the professional world and academic world about the concept and the evaluation of the quality of audit. As the traditional approach of evaluation was not efficient enough in the past, news economic regulations (law Sarbanes Oxley Act) adopted new ways of measurement supporting the evaluation of the quality of auditing processes. The new role of quality evaluation performed from the committee of audit constitutes one of the most important measures substantiate this orientation. The academicians also plead for strengthening of this role of the committee of audit, considering the important place th committee of audit, considering the important place the committee takes in the controlling process. The objective of this research activity is to develop a tool for evaluating the quality of the audit process, enabling the committee to strongly establish the important role given to them with benefits for this committee. The conceptional design and the validation of this tool are carried out within the framework of an experimental protocol, taking procedures of Churchill from other similar disciplines, and adapting them to the context of our research. Integrating qualitative phases (47 discussions with auditors and administrators) and quantitative (142 questionnaires collected from administrators), this step is targeted towards the evaluation of the quality of the process of audit (49 indicators of quality, distributed on six stages of the process), and other elements considering the relation between administrator and auditor, with methods of evaluation of the mission of audit including types of progress reports to be communicated to the auditing committees
Vinsonneau, Emile. "La qualité d'image dans le contexte de la numérisation de livres anciens." Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0057/document.
Повний текст джерелаThe goal of this thesis is to add some tools in order to upgrade image quality when scanning with book digitization.First Chapter talks about image scanner whitout lighting control. This problem focuses to document camera. The goal is to correct lighting. We will see some corrections and we will suggest our method. For this part, we detect pixel's background document and we will rebuild the background of the image by them. With this information, we can correct lighting.Second chapter presents some way to do quality control after digitization, specially out of focus problem. We will enumerate different point of view to analyse and to estimate this information. To validate descriptors, we suggest to blur any picture and to compute blur estimation in order to evaluate precision. After that, we propose to combinate descriptors by machine learning.Third chapter mentions color management problem. Every image devices need to be calibrated. This chapter will expose how to calibrate scanner and explain it. We will see that L*a*b* color space is the connection profil space. To calibrate color, we must transform scanner color space to L*a*b*. We will see, in order to convert information, solution depends color chart used but we show a link between the function and thenumber of patch
Abassi, Hamouda. "Évaluation de la qualité de vie en cardiologie congénitale." Thesis, Aix-Marseille, 2019. http://www.theses.fr/2019AIXM0654.
Повний текст джерелаSurgical and medical advances in the treatment of congenital heart disease (CC) have improved mortality and morbidity. Currently, pediatric cardiologists are focusing on health-related quality of life (QoL) in children and adults with CHD, both in clinical research and in current practice. In the continuation of our research program on QoL in pediatric and congenital cardiology started 10 years ago, this thesis included three QoL studies in patients with CHD: first, a cross-sectional study evaluating QoL in 124 children with CHD aged 5 to 7 years compared to 125 control children of the same age and showing that the QoL of this patient population was similar to that of the general population; then, a comparative cross-sectional study in 555 children with CHD and 279 control children, assessing their respiratory function and correlating QoL scores to ventilatory parameters. In greater detail we found that forced vital capacity (FVC) in CHD children was moderately but significantly impaired compared to healthy children with a restrictive pattern for 20% of them; and finally, a prospective study correlating QoL with time in therapeutic range (TTR) in 121 children under anticoagulants included in a self-monitoring educational program. The results of this study found that the QoL of those children was correlated with the balance of anticoagulant therapy as measured by the TTR.Those QoL studies provided answers to questions from patients, families, patient associations, and caregivers in the field of pediatric and congenital cardiology
Limare, Nicolas. "Recherche reproductible, qualité logicielle, publication et interfaces en ligne pour le traitement d'image." Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2012. http://tel.archives-ouvertes.fr/tel-00783299.
Повний текст джерелаOrtiz, Cayón Rodrigo. "Amélioration de la vitesse et de la qualité d'image du rendu basé image." Thesis, Université Côte d'Azur (ComUE), 2017. http://www.theses.fr/2017AZUR4004/document.
Повний текст джерелаTraditional photo-realistic rendering requires intensive manual and computational effort to create scenes and render realistic images. Thus, creation of content for high quality digital imagery has been limited to experts and highly realistic rendering still requires significant computational time. Image-Based Rendering (IBR) is an alternative which has the potential of making high-quality content creation and rendering applications accessible to casual users, since they can generate high quality photo-realistic imagery without the limitations mentioned above. We identified three important shortcomings of current IBR methods: First, each algorithm has different strengths and weaknesses, depending on 3D reconstruction quality and scene content and often no single algorithm offers the best image quality everywhere in the image. Second, such algorithms present strong artifacts when rendering partially reconstructed objects or missing objects. Third, most methods still result in significant visual artifacts in image regions where reconstruction is poor. Overall, this thesis addresses significant shortcomings of IBR for both speed and image quality, offering novel and effective solutions based on selective rendering, learning-based model substitution and depth error prediction and correction
Mouhoub, Mohamed. "Filtres d'ordre, filtre médian récursif : analyse et évaluation des performances en traitement d'image". Lyon, INSA, 1989. http://www.theses.fr/1989ISAL0017.
Повний текст джерелаGuéguin, Marie. "Évaluation objective de la qualité vocale en contexte de conversation." Rennes 1, 2006. https://tel.archives-ouvertes.fr/tel-00132550.
Повний текст джерелаPénochet, Jean-Claude. "Vers une démarche qualité en psychiatrie." Montpellier 1, 1994. http://www.theses.fr/1994MON1T037.
Повний текст джерелаUrrutiaguer, Daniel. "Médiations et conventions dans l'évaluation de la qualité théâtrale." Paris 10, 2001. http://www.theses.fr/2001PA100084.
Повний текст джерелаWith an essentialist modelling of quality, which supposes that its perception is objective as in the models of product differenciation, the role of mediators is reduced to giving the true information on the artistic characteristics. On the other hand a pragmatic conception, for which quality emerges from listening to the performance and is subjectively perceived depending on the past experiences, justifies that the groups of mediators influence the anticipation of quality when audiences trust their appraisal. In the same way, the assesments of the experts of public authorities, the drama critics and the theatre programmers stratify the world of theatrical art. A frame of common references is necessary to recognize the artistic forms, interpret symbols and steady one's tastes. It supposes that attendues and producers share some conventions. A set of detailed data on theatrical institutions in 1995 and 1996 was used to model the explanatory variables of their demand. They support an hypothesis on the opposition of attendees' adherence to the scales of judgement of drama critics and theatre programmers. This fact could be interpreted as the coexistence of two orders of quality which are connected to the same convention of reticular and inspired quality but are differenciated between a media and an institutional orders. The study of market profiles from a version of white's model shows that the producers' stratégies are diverse for a same order of quality. It is a tool suited to classify failure and succes in the short-tern adaptation of the programmation to the evolution of attendance
Robelet, Magali. "Les figures de la qualité des soins : rationalisations et normalisation dans une économie de la qualité." Aix-Marseille 2, 2002. http://www.theses.fr/2002AIX24009.
Повний текст джерелаLassalle, Julie. "Etude de l'influence de la qualité audiovisuelle sur la qualité d'expérience du spectateur : combinaison d'indicateurs subjectifs, physiologiques et oculaires." Télécom Bretagne, 2013. http://www.telecom-bretagne.eu/publications/publication.php?idpublication=14159.
Повний текст джерелаIn a strongly competitive context, one of the main stakes for the actors of the audiovisual services offer is to guarantee to the spectator an optimal Quality of Experience (QoE). Nowadays, QoE is often limited to the perception of the audiovisual quality (AVQ) received by the system. It is mainly measured through the collection of rates given by testers onto quality scales, after visualization and listening of the AV sequences treated by one or several technologies to be evaluated. These subjective tests are following procedures recommended by the International Telecommunication Union. However, the restored quality can affect some factors of QoE (fatigue, effort, etc. ) which are not reflected by the quality scores. A method considering the evaluation either of the AV quality only received but of the quality of experience, widely considered, could allow to report better the influence of the sound and image quality on the spectator. The present work is centered on the research of an alternative method to current methods of quality assessment for multimedia applications in a context of viewing/listening of 2D or 3D AV contents. The proposed approach addresses the QoE in terms of analysis of subjective indicators and tonic physiological (electrodermal activity, heart rate, peripheral cutaneous temperature, blood volume pulse) and oculars indicators (PERCLOS, duration and frequency of the blinking of the eye, number of saccadic movements, pupillary diameter). Physiological and ocular measures have for advantage not to be subjected to the biases of the subjective measures (representativeness, scales, etc. ) and to reflect phenomena such as fatigue or mental effort, potentially induced by the presence of audio and/or video degradations, which may be critical in terms of QoE. Two protocols were tested to study the relevance of this approach. The results showed that QAV modulates the subjective measures and have putted forward the insufficiency of quality rates to reflect faithfully this effect. The impact of the quality on the physiological and ocular measures is less obvious. A set of factors in particular connected to certain attributes of the test contents, as the dynamics or the luminosity, would have been able to mask or decrease the quality effects observation on gathered measures. However, two of the physiological indicators reacted to the presence of audio and/or video degradations when these were accumulated to the detrimental effect of other factors (3D video or test period effect).
Reine, Gilles. "Qualité de la vie et schizophrénie." Aix-Marseille 2, 2005. http://www.theses.fr/2005AIX20671.
Повний текст джерелаWe developed a self-rated instrument for evaluating subjective quality of life in patients suffering from schizophrenia : the S-QoL. The S-QoL includes 41 questions and 8 dimensions (psychological well-being, self esteem, physical well-being, relations with family, relations with frieds, sentimental life, autonomy, resilience), with a global index. We present the results of validation studies showing that the S-QoL is valid, reliable and has good responsiveness. The S-QoL has been compared with two standard instruments : the QoLI and the SF-36. In regression analysis studies, explanatory factors of the S-QoL are : paranoid symptoms, hostility, depression, age, previous comorbidity with alcohol abuse and depression, daily activities, and the number of weekly contacts with family and friends. Preliminary results show that self-evaluation with the S-QoL is not influenced by memory and executive function deficits but has statistical relationships with insight. The interest of self-rating has been verified by comparing evaluations of patients and referent health professionals. A preliminary study describes quality of life from the caregiver's point of view
Raymond, Gérard. ""Le concept de qualité : une évaluation empirique des éléments d'information de la qualité d'un produit agro-alimentaire"." Grenoble 2, 1987. http://www.theses.fr/1987GRE21016.
Повний текст джерелаThis research answers a main question : determine which attribute has more value than an other and for which quality aspect. An analysis framework is developped to interpret the concept multidimentionality. Three research axes are developped : 1- which are the product quality attributes used by the consumer. 2- which is their relative importance. 3- which is personnal factors influence on product quality attributes. A qualitative (interviews and prompt protocols) and quantitative methods (conjoint measurement, cluster and discriminant analysis, log-linear and peterson & mahajan partial square omega) are used to test the hypotheses. Two principal theorical consequences can be drawn from this research. The olson hypothesis cannot been generalized and no personnal factors allow to differentiate a group of consumers from another
Bosc, Emilie. "Compression des données Multi-View-plus-Depth (MVD) : De l'analyse de la qualité perçue à l'élaboration d'outils pour le codage des données MVD." Phd thesis, INSA de Rennes, 2012. http://tel.archives-ouvertes.fr/tel-00777710.
Повний текст джерелаCluzel-Métayer, Lucie. "Le service public et l'exigence de qualité." Paris 2, 2004. https://buadistant.univ-angers.fr/login?url=https://bibliotheque.lefebvre-dalloz.fr/secure/isbn/9782247099269.
Повний текст джерелаThe demand for quality has become inevitable for public utility, as an expression of the will of public action to satisfy users' needs. At first introduced in the form of participative approaches, quality is currently at the center of quality assurance and responsabilisation approaches. This managerial precept has adjusted itself and reflects the emergence of a distinctive notion of quality, specific to public utilities. Therefore, it has had unexpected legal repercussions. Moreover, administrative quality's components, such as transparence, simplicity, receptivity or promptness are requirements widely included in the field of Law. The demand for quality is thus seized by Law and everything leads to believing that it has become a principle of public utility regulations, completing the original triptyque
Vian, Marie. "Qualité de l'évaluation ergonomique à distance et asynchrone." Paris 8, 2012. http://www.theses.fr/2012PA083970.
Повний текст джерелаWith the contribution of information and communication technologies, the practice of the researcher and the ergonomist has been modified. The ergonomist has traditionally been close to the user, being physically present, and now can operate remotely and / or be absent. Extending the previous works of Brunswik (1947), Leplat (1978, 1997), Loiselet, Hoc and Denecker (1999, 2000) and Hoc (2008), this thesis focuses on data collected with these technologies during user tests, by first defining the purpose of their collection, internal validity and external validity. This theoretical work has allowed us to develop AVIVE [Adéquation Validité Interne Validité Externe], a method to estimate the reliability of data quality. AVIVE method was used in three experiments to assess the dimensions of quality on the remote testing situations. The first experiment compares the use of the devices, paper or computer, to a post-test questionnaire. The third experiment, which is exploratory, is focused on the use of Bulletin Board and its adaptation to the ergonomic assessment. The discussion focuses on 1) te interest of the AVIVE method, 2) the improvements to be made, 3) on systematic use to new observation mechanisms in order to assess the degree of data quality and 4) on the systematic use of results to choose the method and test situation that best fit with the quality dimensions
Alemu, Tigist. "Évaluation des Performances des Mécanismes de Qualité de Service dans l'Internet." Phd thesis, Université Montpellier II - Sciences et Techniques du Languedoc, 2004. http://tel.archives-ouvertes.fr/tel-00011157.
Повний текст джерелаCantin, François. "Évaluation de la qualité lumineuse d'un environnement de travail éclairé naturellement." Thesis, Université Laval, 2008. http://www.theses.ulaval.ca/2008/25625/25625.pdf.
Повний текст джерелаThis research aims to develop a methodology for the assessment of daylight quality in individual office spaces. The proposed methodology is based on performance indicators related to illuminance, distribution (variability) , glare and directivity. The calculations are performed with the Radiance Lighting Simulation System for a South-West and a North-West oriented office located on the fifth floor of the Caisse de dépôt et placement (CDP) in Montreal. The daylight conditions of these offices are studied under a series of clear skies and an overcast sky. The selected indicators for the assessment of daylight quality are the vector/scalar illuminance ratio, the altitude of illuminance vector, the luminance difference index (LD index), the useful daylight illuminance (UDI) and the size of sunlight patches. The literature encourages the researcher to use advanced indicators like these in order to go beyond a simple study of horizontal illuminance and to deepen the analysis of luminous environment. The results allow a detailed performance assessment for each office. Furthermore, the analysis of the results underline the complementarity of the indicators, i.e., the necessity to compare them to adequately assess daylight quality. Finally, polar diagrams are used to synthesize the results. This graphical approach introduces a useful method to represent luminous ambiances.
Jung, Mathieu. "Évaluation univariante de la qualité des images par une approche neuronale." Toulouse, ENSAE, 2000. http://www.theses.fr/2000ESAE0012.
Повний текст джерелаNouri, Anass. "Cartes de saillances et évaluation de la qualité des maillages 3D." Caen, 2016. https://hal.archives-ouvertes.fr/tel-01418334.
Повний текст джерелаThe glance of each human being is attracted by specific areas into 3D objects (that can be represented by meshes). This attraction depends on the degree of saliency exposed by these areas. The first goal of this thesis is to propose an approach for detecting visual salient areas on 3D non-colored meshes. We consider that a vertex as salient if it strongly stands out from its local neighborhood and if its geometric configuration is different from its adjacent vertices. For this, we characterize the surface of the 3D mesh by the use of a local vertex de-scriptor in the form of an adaptive patch. This descriptor is used as a basis for similarity computation and integrated into a weighted multi-scale saliency computation. We propose also an extension of our visual saliency model to 3D colored meshes. Four saliency-based applications were developed after the validation of the saliency detection results with a pseudo ground truth. The first and the second one concern respectively the optimal viewpoint selection and the adaptive compression of 3D non colored meshes. The third one sharpens the details of a 3D colored mesh, and the fourth smooths adaptively its colors. The second aim is to propose a novel perceptual full reference metric for the quality assessment of 3D meshes. Given a 3D reference mesh (reputed devoid from any distorsions) and a 3D distorted mesh as inputs of this metric, the goal is to assess the perceived quality of the distorted mesh by providing a fidelity score which must be as close as possible to the humans scores. As visual saliency is a perti-nent information for our visual system, its use in the pipeline of the quality metric is natural. We use two properties of 3D meshes for evaluating their perceived quality : the visual saliency and the roughness. The multi-scale saliency map is used for the extraction of the structural informations of the 3D mesh and the roughness map for the account of the visual masking effect. We introduce 4 comparison functions between 2 corresponding local neighborhoods in order to estimate the structural differences between them. We combine these functions with a weighted Minkowski sum so as to obtain a final quality score. The third objectif of this thesis is to provide an approach for the difficult problem of the no reference quality assessment of 3D meshes. On the contrary to full reference metrics, this category is considered as the thorniest since the reference version of the 3D mesh is not used. Similarly to the full reference metric, we suppose that the visual quality of a 3D mesh is more affected when the salient areas of the mesh are affected and vice versa. We begin by segmenting the mesh into a number of Superfacets which represent the local patches in this context. Then we affect to each vertex of a Superfacet its respective values of saliency and roughness. Afterward, we extract four local characteristics of each Superfacet (mean saliency, standard-deviation saliency, covariance saliency and mean roughness). Variations of these 4 characteristics quantify effectively the distorsions that a mesh may undergo. Finally, we perform a learning step based on SVMs (Support Vectors Machines) using the constructed feature vector , To move from a vectorial representation to a final quality score, we use a regression SVM scheme
Goudet-Guitton, Ghylène. "Ovocytes équins : optimisation de la production et évaluation de la qualité." Tours, 1998. http://www.theses.fr/1998TOUR4002.
Повний текст джерелаVilain, Loïc. "Conception et évaluation d'un système de surveillance : application au serrage hydraulique." Lille 1, 1998. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/1998/50376-1998-161.pdf.
Повний текст джерелаHattab, Insaf. "Qualité et perception de la qualité d'audit : le cas des auditeurs et audités en Tunisie." Thesis, Bordeaux, 2014. http://www.theses.fr/2014BORD0324.
Повний текст джерелаThis research questions the measure of audit quality by taking a perceptual concept. Mobilizing tworesearch approaches: A functional approach that puts into evidence the criteria that promote atrade. This is reached through its “ideal type”, and the néo-wébérien approach that outlines theideology from which a trade is defined to prove its legitimacy. The interaction between these twoapproaches allows a global vision of the phenomenon of the audit quality. This concept will beaddressed through the perception that the auditors and the audited get in the measure that onlysubjectivities can be used to get closer of a normalized level.. The phenomenon of the expectation gapemerges from this problematic through the shift of the perceptions. A psychological socialframework is also mobilized to understand the nature of the social link between these two actors.To apprehend these perceptions 150 answers of auditors and 88 audited are examined in a Tunisiancontext. These perceptions are then confronted. The analysis of the results reveals perceptions thatare guided by personal values of the individuals which don’t systematically influence the trustestablished between the two parties. The perceptions of the two actors are nonetheless globallydivergent; the expectation gap is hence truly present in Tunisia. The auditor is aware that hisperceptions are different from his client’s demands
Poirier, Pascal, and Pascal Poirier. "Outils automatiques d'évaluation de la qualité des données : suivi en temps réel de la qualité de l'eau d'un ruisseau urbain." Master's thesis, Université Laval, 2015. http://hdl.handle.net/20.500.11794/25816.
Повний текст джерелаLors d’un suivi en temps réel de la qualité de l’eau d’une rivière, une quantité innombrable de données peut être récoltée permettant ainsi une bonne description des dynamiques changeant rapidement. Cependant, des questions s’imposent. Quelle est la qualité des données mesurées en temps réel? Quels sont les effets de données de mauvaise qualité sur les objectifs associés à leur utilisation? Ce mémoire tente de résoudre cette problématique en présentant des outils automatiques d’évaluation de la qualité des données. Ces outils sont généraux et simples, en ce sens qu’ils s’appliquent à différents emplacements (rivière, STEP, égout, etc.) et qu’ils sont basés sur des méthodes univariées faciles à implanter. Suite à l’application de ces outils, la qualité des données est connue et accrue favorisant ainsi l’atteinte des objectifs reliés à un suivi en temps réel. Leur application est démontrée sur des données mesurées lors d’un suivi en temps réel de la qualité de l’eau d’un ruisseau urbain effectué à l’aide de la station monEAU.
During real-time water quality monitoring in river systems, a huge amount of data is produced which allows a better description of the rapidly changing dynamics compared to spot sampling methods. However, what is the quality of the measured data and what are the impacts of poor data quality on the objectives pursued during real-time water quality monitoring? Therefore, this master thesis proposes automatic data quality assessment tools to tackle this issue. These tools are general and simple, which means that they can be applied to any type of water and that they are based on easy-to-implement univariate methods. Following the application of these tools, data quality will be improved and known as such and will allow to better achieve the objectives of a real-time water quality monitoring project. The application of these tools is demonstrated on data collected during real-time water quality monitoring of an urban river performed using a monEAU station.
During real-time water quality monitoring in river systems, a huge amount of data is produced which allows a better description of the rapidly changing dynamics compared to spot sampling methods. However, what is the quality of the measured data and what are the impacts of poor data quality on the objectives pursued during real-time water quality monitoring? Therefore, this master thesis proposes automatic data quality assessment tools to tackle this issue. These tools are general and simple, which means that they can be applied to any type of water and that they are based on easy-to-implement univariate methods. Following the application of these tools, data quality will be improved and known as such and will allow to better achieve the objectives of a real-time water quality monitoring project. The application of these tools is demonstrated on data collected during real-time water quality monitoring of an urban river performed using a monEAU station.