Mostra el registre d'ítem simple
Towards precise outdoor localisation based on image recognition
dc.contributor | Marqués Acosta, Fernando |
dc.contributor | Adamek, Tomasz |
dc.contributor.author | Trzcinski, Tomasz Piotr |
dc.contributor.other | Universitat Politècnica de Catalunya. Departament de Teoria del Senyal i Comunicacions |
dc.date.accessioned | 2016-05-09T06:38:02Z |
dc.date.available | 2016-05-09T06:38:02Z |
dc.date.issued | 2010-07-10 |
dc.identifier.uri | http://hdl.handle.net/2117/86739 |
dc.description.abstract | In recent years significant progress has been made in the field of visual search, mostly due to the introduction of powerful local image features. At the same time, a rapid development of mobile platforms enabled deployment of image retrieval systems on mobile devices. Various mobile applications of the visual search have been proposed, one of the most interesting being geo-localization service based on image recognition and other positioning information. This thesis attempts to advance the existing visual search system developed at Telefonica I+D Barcelona so it could be used for high precision geo-localization. In order to do so, this dissertation tackles two significant challenges of image retrieval: improvement in robustness of the detection of similarities between images and increase of discriminatory power. The work advances the state-of-the-art with three main contributions. The first contribution consists of the development of an evaluation framework for visual search engine. Since the assessment of any complex system is crucial for its development and analysis, an exhaustive set of evaluation measures is selected from the relevant literature and implemented. Furthermore, several datasets along with the corresponding information about correct correspondences between the images have been gathered and unified. The second contribution considers the representation of image features describing salient regions and attempts to alleviate the quantization effects introduced during its creation. A mechanism that in the literature is commonly referred to as soft assignment is adapted to a visual search engine of Telefonica I+D with several extensions. The third and final contribution consists of a post-processing stage that increases discriminative power by verification of local correspondences' spatial layout. The performance and generality of the proposed solutions has been analyzed based on extensive evaluation using the framework proposed in this work. |
dc.language.iso | eng |
dc.publisher | Universitat Politècnica de Catalunya |
dc.rights | Attribution-NonCommercial-NoDerivs 3.0 Spain |
dc.rights.uri | http://creativecommons.org/licenses/by-nc-nd/3.0/es/ |
dc.subject | Àrees temàtiques de la UPC::Enginyeria de la telecomunicació::Processament del senyal::Reconeixement de formes |
dc.subject.lcsh | Location-based services |
dc.subject.lcsh | Pattern recognition systems |
dc.title | Towards precise outdoor localisation based on image recognition |
dc.type | Master thesis (pre-Bologna period) |
dc.subject.lemac | Geolocalització, Serveis de |
dc.subject.lemac | Reconeixement de formes (Informàtica) |
dc.rights.access | Open Access |
dc.audience.educationlevel | Estudis de primer/segon cicle |
dc.audience.mediator | Escola Tècnica Superior d'Enginyeria de Telecomunicació de Barcelona |
dc.audience.degree | ENGINYERIA DE TELECOMUNICACIÓ (Pla 1992) |