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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Audio segmentation, classification and visualization

Zhang, Xin January 2009 (has links)
This thesis presents a new approach to the visualization of audio files that simultaneously illustrates general audio properties and the component sounds that comprise a given input file. New audio segmentation and classification methods are reported that outperform existing methods. In order to visualize audio files, the audio is segmented (separated into component sounds) and then classified in order to select matching archetypal images or video that represent each audio segment and are used as templates for the visualization. Each segment's template image or video is then subjected to image processing filters that are driven by audio features. One visualization method reported represents heterogeneous audio files as a seamless image mosaic along a time axis where each component image in the mosaic maps directly to a discovered component sound. The second visualization method, video texture mosaics, builds on the ideas developed in time mosaics. A novel adaptive video texture generation method was created by using acoustic similarity detection to produce a resultant video texture that more accurately represents an audio file. Compared with existing visualization methods such as oscilloscopes and spectrograms, both approaches yield more accessible illustrations of audio files and are more suitable for casual and non expert users.
42

Particle Systems : A Comparison Between Octree-based and Screen Space Particle Collision

Kåvemark, Nils, Miloradovic, Stevan January 2018 (has links)
Background. Real-time applications like video games use particle systems for special effects to add visual aesthetics and realism. However, when complex behaviour that requires interaction between particles and geometry is desired, problems arise. The developer has to choose between having consistent and precise collisions or higher performance. This thesis goes over two particle collision implementations that try to solve these problems. Objectives. The objective of this thesis is to create an application that has support for two collision methods and compare them on performance and accuracy to decide which one is more suitable for real-time applications. Methods. To answer the research questions proposed the implementation methodology was used, as a result of that, a 3D-application was created using the graphics API OpenGL to render. Two simple GPGPU implementations were made for each method, to have a more fair comparison. To be able to measure performance the application logs frame-time every frame. A fixed time-step was added in the main loop to allow the users to stop the application at a certain time to be able to capture images of the scene that will then be used for pixel comparison to measure accuracy. Results. Screen space particle collision is almost three times faster than the octree-based method. Both methods had different behavior in both the real-time simulation and at specific time-steps resulting in loss of accuracy from the screen space particle collision. Conclusions. The tests allowed the authors to show that the screen space particle collision is faster and scales better than the octree-based method. However, it did lack precision as shown by the comparison by the images taken from the test. For particle simulations that require consistent and accurate collision checks the octree-based method is better due to the fact that screen space particle collision can result in false collisions checks and has problems with hidden geometry.
43

Week 08, Video 07: Creating Textures in Photopea

Marlow, Gregory 01 January 2020 (has links)
https://dc.etsu.edu/digital-animation-videos-oer/1060/thumbnail.jpg
44

A Dental Microwear Texture Analysis of the Early Pliocene African Ursid Agriotherium africanum (Mammalia, Carnivora, Ursidae)

Stynder, Deano D., DeSantis, Larisa R.G., Donohue, Shelly L., Schubert, Blaine W., Ungar, Peter S. 01 December 2019 (has links)
The craniodental morphology of the early Pliocene ursid Agriotherium africanum has been studied extensively to reveal aspects of its dietary ecology. Results suggest that this large-bodied, long-legged, short-faced African native primarily consumed vertebrate matter. While many carnivoran families exhibit a clear functional relationship between craniodental form and performance on the one hand, and dietary behavior on the other, this is not always the case with Ursidae. Because of uncertainties regarding the appropriateness of using craniodental form to investigate ursid diets, questions still linger about the dietary ecology of Ag. africanum. Here, we report on a dental microwear texture analysis of six Ag. africanum lower second molars from the South African fossil site of Langebaanweg. Results support morphological evidence that suggests a diet focused on vertebrate soft tissue and bone. Unfortunately, results cannot clarify questions about mode of acquisition.
45

Procedural Textures in CET : Investigating the feasibility of implementing procedural textures in CET / Procedurell texturgenerering i CET

Oscar, Sandell, Adam, Schuber January 2023 (has links)
Applications with 3D graphics often utilize high-resolution image textures to enhance re-alism. Image textures are stored as large files, which can result in significant storage spaceallocation for the application. Furthermore, image textures are also disadvantaged becausethey are static and lack flexibility. These issues could be addressed through the use of pro-cedurally generated textures, referred to as procedural textures. The thesis explored andinvestigated the feasibility of implementing procedural textures in Configura’s 3D interiordesign software CET. A procedural texture was implemented that showcased many posi-tive attributes of procedural textures, including: reduced storage space requirements, un-limited resolution, and versatile customization. To accomplish this, an iterative approachwas used as the methodology, where the procedural texture was gradually incorporatedinto CET. The procedural texture later underwent a performance evaluation. The resultsshowed that traditional textures allocate an order of magnitude more storage space thanthe procedural approach. Despite this, renderings times in CET remained similar. In tworendering tests, the procedural texture was measured to be 9% faster in the first test, and 3.4% slower in the second test. In conclusion, procedural texture have many benefits thatcompanies such as Configura could take advantage of.
46

Sedimentation and Diagenesis in Sandstones of the Mannville Group (Lower Cretaceous), Southeastern Alberta

Kavanagh, Paul 05 1900 (has links)
<p> Lower Cretaceous Mannville Group sandstones of Alberta were deposited in non-marine and marginal environments. A shallow sea transgressed several times over the study area and left evidence of tidal action. The proportion of rock fragments increases from Lower Mannville to Upper Mannville sandstones due to the uplifting of strata to the west. </p> <p> Observed petrographic and SEM textures indicate that authigenic pyrite, quartz and calcite cements were precipitated in that order followed by the dissolution of carbonate material and feldspar grains with the simultaneous precipitation of kaolinite and quartz. The secondary (or dissolution) porosity is the result of an influx of acidic pore waters. This secondary porosity is best developed in the Ellerslie Sandstone because its remnant intergranular porosity and permeability are superior to the porosity and permeability in the overlying sandstones. The present degree of diagenesis in the sandstones is largely controlled by the permeability of the rock. </p> / Thesis / Bachelor of Science (BSc)
47

Coronite Amphibolites from the Whitestone Area, Parry Sound, Ontario

Mummery, Robert 12 1900 (has links)
<p> Coronite amphibolites located near the western contact of the. Whitestone Lake Anorthosite were studied in the field and laboratory in order to determine their origin. The corona textures consisted of garnet cores surrounded by complete rims of plagioclase, which in turn were occasionally surrounded by partial or complete rims of garnet or pyroxene. The development of coronas is also accompanied by an increase in pyroxene in the rock, and the development of cryptic zoning in both garnets and plagioclases. Whole rock X-Ray Fluorescence and mineral electron-probe analyses were determined for suites of samples collected. The analyses suggest that corona development occurred isochemically as the result of a contact metamorphism induced by anorthosite emplacement and mineral reactions have been proposed. Microprobe analyses of the garnets led to the establishment of models for the production of garnets in mafic assemblages and models for the observed cryptic zoning in the garnets~ It was concluded that the coronites represent the transition from almandine amphibolite facies to clinopyroxene subfacies of granulite metamorphism of garnetiferous amphibolites. This transition results from the thermal metamorphism induced by the emplacement of the Whitestone lake anorthosite. </p> / Thesis / Doctor of Philosophy (PhD)
48

ADVANCED NEURAL NETWORK CLUSTERING TECHNIQUES FOR LIQUID CRYSTAL TEXTURE CLASSIFICATION

Karaszi, Zoltan 29 July 2013 (has links)
No description available.
49

Depth texture synthesis for high resolution seamless reconstruction of large scenes

Labrie-Larrivée, Félix 09 July 2018 (has links)
La numérisation 3D de scène à grande échelle est un problème complexe sans solution à la fois précise, rapide et abordable. Les scènes à grande échelle comme les façades d'édices comportent cependant des éléments répétitifs (fenêtres, briques, panneaux de bois) qui peuvent être utilisés pour améliorer le processus de numérisation. Notre approche, Depth Texture Synthesis, utilise un scan haute résolution d'un de ces éléments, effectué avec un scanneur RGBD, et transmet cette résolution élevée aux endroits où l'élément est répété ailleurs dans la scène. Cette transmission s'effectue suivant l'information fournie par une reconstruction SfM. Pour effectuer une procédure de Depth Texture Synthesis, la façade de l'édice est simplifiée en une géométrie planaire qui nous sert de canevas. Sur ce canevas nous projetons l'information RGB ainsi que l'information de profondeur du modèle échantillon haute résolution et du modèle SfM basse résolution. Ensuite, un algorithme puissant de synthèse de texture 2D est employé pour transmettre l'information de profondeur haute résolution suivant les patrons de profondeur basse résolution et d'information RGB. La nouvelle carte de profondeur haute résolution peut alors être reconvertie en modèle 3D pour un résultat beaucoup plus réaliste et visuellement détaillé que la reconstruction SfM. Il est aussi intéressant de noter que notre approche est beaucoup moins fastidieuse qu'un scan complet de la scène utilisant des scanneurs RGBD. Les outils utilisés (Kinect v2 et appareil photo) sont aussi très abordables en comparaison avec le Lidar. / Large scenes such as building facades are challenging environments for 3D reconstruction. These scenes often include repeating elements (windows, bricks, wood paneling) that can be exploited for the task of 3D reconstruction. Our approach, Depth Texture Synthesis, is based on that idea and aims to improve the quality of 3D model representation of large scenes. By scanning a sample of a repeating structure using a RGBD sensor, Depth Texture Synthesis can propagate the high resolution of that sample to similar parts of the scene. It does so following RGB and low resolution depth information of a SfM reconstruction. To handle this information the building facade is simplified into a planar primitive and serves as our canvas. The high resolution depth of the Kinect sample and low resolution depth of the SfM model as well as the RGB information are projected onto the canvas. Then, powerful image based texture synthesis algorithms are used to propagate the high resolution depth following cues in RGB and low resolution depth. The resulting synthesized high resolution depth is converted back into a 3D model that greatly improves on the SfM model with more detailed, more realistic looking geometry. Our approach is also much less labor intensive than RGBD sensors in large scenes and it is much more affordable than Lidar.
50

Outils et méthodes d'analyse d'images 3D texturées : application à la segmentation des images échographiques

Paulhac, Ludovic 24 November 2009 (has links) (PDF)
Le travail présenté dans cette thèse s'inscrit dans le domaine de l'analyse d'images texturées et plus particulièrement d'images 3D (ensembles de voxels). Pour ces dernières, les difficultés d'analyse sont principalement dues à la très grande quantité d'informations à prendre en compte et à traiter, ce qui rend inefficaces les méthodes dédiées aux images 2D. De plus, outre le faible nombre de travaux proposant des méthodes réellement 3D, la majeure partie des méthodes d'analyse de textures existantes n'ont pas une applicabilité très étendue et sont incapables d'identifier certaines classes de textures. En comparaison, le système visuel humain s'adapte à tous types de textures, même en présence d'un contexte défavorable. Les textures sont donc facilement discernées par l'humain, mais très difficiles à définir sous forme d'un modèle mathématique unique offrant une description purement quantitative. Partant de l'hypothèse qu'il est plus pertinent de décrire une texture avec des adjectifs qualificatifs (description qualitative) plutôt qu'avec un modèle mathématique unique, nous avons choisi dans un premier temps de définir un nouvel ensemble de descripteurs de textures permettant une caractérisation qualitative des textures contenues dans les images 3D. Il est difficile de produire une définition consensuelle du terme "texture". Néanmoins, la première contribution de cette thèse est la proposition d'un nouvel ensemble de caractéristiques de textures solides construit à partir de propriétés de textures facilement appréhendable par l'utilisateur humain. Ces nouveaux descripteurs permettent entre autres de décrire des propriétés texturales telles que la directionnalité, la rugosité et le contraste. La deuxième contribution de cette thèse correspond aux techniques multi-résolutions que nous proposons d'exploiter pour extraire ces caractéristiques des images 3D, techniques basées sur une décomposition en ondelette couplée à une analyse des composantes géométriques contenues dans les représentations obtenues. Enfin, le système de segmentation interactif d'images échographiques 3D de la peau, intégrant nos descripteurs de textures solides, couplé à un mécanisme de clustering et à une interface homme-machine adaptée constitue, selon nous, une troisième contribution. Ce système nous a permis de valider expérimentalement la robustesse et la généricité de nos propositions, et intéresse aujourd'hui de nombreux acteurs du monde de la santé (médecins, dermatologues, industriels, ...).

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