Guillaume Touya

Guillaume Touya
Institut national de l’information géographique et forestière | IGN · LASTIG

PhD

About

125
Publications
33,785
Reads
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1,726
Citations
Introduction
Guillaume Touya is a senior researcher at the LASTIG, a joint lab of IGN France, the French national mapping agency, and Univ. Gustave Eiffel. He is the Principal Investigator of the ERC Consolidator Grant LostInZoom. Guillaume does research in Cartography, Artificial Intelligence, and Geoinformatics (GIS).
Additional affiliations
August 2017 - August 2017
Institut national de l’information géographique et forestière
Position
  • Head of Department
September 2004 - present

Publications

Publications (125)
Article
Full-text available
Tactile cartography has always been a niche topic, but even among tactile cartographers, little attention has been paid to thematic tactile maps. Thematic maps are used in education and the lack of such materials makes it difficult to fulfill particular subjects’ curriculums. In this research, we propose a methodology for automatic compilation of l...
Article
Full-text available
Accessibility to tactile maps is limited due to their expensive and time-consuming development. Acceleration of their production requires standardized design guidelines that consider symbol design and production methods. In this paper, based on a review of research and best practice, we summarize knowledge on how to design tactile maps properly and...
Article
Full-text available
The adoption of technology in urban participatory planning with tools such as Virtual Geographic Environments (VGE) promises a broader engagement of urban dwellers, which should ultimately lead to the creation of better cities. However, the authorities and urban experts show hesitancy in endorsing these tools in their practices. Indeed, several par...
Article
Full-text available
Recently, many researchers tried to generate (generalised) maps using deep learning, and most of the proposed methods deal with deep neural network architecture choices. Deep learning learns to reproduce examples, so we think that improving the training examples, and especially the representation of the initial geographic information, is the key is...
Article
Full-text available
Crossing an intersection is a challenge for visually impaired people. While tactile maps can be a medium for appropriating this complex space, they benefit from being complemented by audio information. In this paper we propose a data model to describe an intersection, the paths that allow to cross it, and their accessibility attributes. We also pre...
Article
Full-text available
Deep learning techniques have recently been experimented for map generalization. Although promising, these experiments raise new problems regarding the evaluation of the output images. Traditional map generalization evaluation cannot directly be applied to the results in a raster format. Additionally, the internal evaluation used by deep learning m...
Poster
Full-text available
Explorer la théorie des ancres et les espaces cognitifs dans la cartographie multi-échelle. Maïeul GRUGET & Guillaume TOUYA LASTIG, Univ Gustave Eiffel, ENSG, IGN Votre carte mentale pourrait modifier la manière dont vous percevez une cartographie multi-échelle. Vers un zoom cognititif ancré ?
Article
Full-text available
The spread of COVID-19 has motivated a wide interest in visualization tools to represent the pandemic’s spatio-temporal evolution. This tools usually rely on dashboard environments which depict COVID-19 data as temporal series related to different indicators (number of cases, deaths) calculated for several spatial entities at different scales (coun...
Article
Full-text available
For the past twenty years, the adoption of Virtual Geographic Environments is thriving. This democratization is due to numerous new opportunities offered by this medium. However, in participatory urban planning these interactive 3D geovisualizations are still labeled as very advanced means, and are only scarcely used. The involvement of citizens in...
Article
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LostInZoom is a new research project that will seek to design novel ways of zooming into multi-scale maps, to overcome the desert fog effect that occurs with current multi-scale cartography techniques. The desert fog effect makes you feel lost for a few seconds after a zoom in or out, because the map has changed. The idea developed in this project...
Article
While the recent progress on automated generalisation helped National Mapping Agencies to derive topographic maps more and more quickly, there are still practical cartographic issues that require attention. For instance, embankments are represented with line symbols showing the slope of the embankment. This paper proposes an automated algorithm cal...
Article
The spatial analysis of health data usually raises geoprivacy issues. Due to the virulence of COVID-19, scientists and crisis managers do need to analyze the distribution and spread of the disease with spatially precise data. In particular, it is useful to locate each case on a map to identify clusters of cases. To allow such analyses without breac...
Article
Cartographic generalization is a process similar to text summarization that transforms a map when scale is reduced. Cartographic generalization simplifies the map content while preserving as much as possible the initial characteristics and spatial relations of the map. The automation of this process requires a deep understanding of the context of e...
Article
Full-text available
This article presents how a generative adversarial network (GAN) can be employed to produce a generalised map that combines several cartographic themes in the dense context of urban areas. We use as input detailed buildings, roads, and rivers from topographic datasets produced by the French national mapping agency (IGN), and we expect as output of...
Conference Paper
Full-text available
The use of deep learning techniques for map generalisation raises new problems regarding the evaluation of the results: (1) images are used as input/output instead of vector data; (2) the deep learning processes do not guarantee results that follow cartographic principles; (3) the deep learning models are black boxes that hide the causal mechanisms...
Article
Full-text available
Les courbes de niveau sont l'un des éléments clés des cartes topographiques, car elles facilitent la compréhension du terrain. Mais elles ne sont plus dessinées par des cartographes, elles sont la plupart du temps automatiquement dérivées de modèles numériques de terrain (MNT). Malgré de réels progrès dans cette dérivation automatisée, certains pay...
Preprint
Full-text available
Background: The spatio-temporal analysis of cases is a good way an epidemic, and the recent COVID-19 pandemic unfortunately generated a huge amount of data. But analysing this raw data, with for instance the address of the people who contracted COVID-19, raises some privacy issues, and geomasking is necessary to preserve both people privacy and the...
Preprint
Full-text available
The spatial analysis of health data usually raises geoprivacy issues. But with the virulence of COVID-19, scientists and crisis managers do need to analyse the spatio-temporal distribution and spreading of the disease with spatially precise data. In particular, it is useful to locate each case on a map to identify clusters of cases in space and tim...
Article
Full-text available
Visually impaired people cannot use classical maps but can learn to use tactile relief maps. These tactile maps are crucial at school to learn geography and history as well as the other students. They are produced manually by professional transcriptors in a very long and costly process. A platform able to generate tactile maps from maps scanned fro...
Article
Full-text available
Though Volunteered Geographic Information (VGI) has the advantage of providing free open spatial data, it is prone to vandalism, which may heavily decrease the quality of these data. Therefore, detecting vandalism in VGI may constitute a first way of assessing the data in order to improve their quality. This article explores the ability of supervis...
Article
Full-text available
Cartographic generalization research has focused almost exclusively in recent years on topographic mapping, and has thereby gained an incorrect reputation for having to do only with reference or positional data. The generalization research community needs to broaden its scope to include thematic cartography and geovisualization. Generalization is n...
Article
Full-text available
Among cartographic generalisation problems, the generalisation of sinuous bends in mountain roads has always been a popular one due to its difficulty. Recent research showed the potential of deep learning techniques to overcome some remaining research problems regarding the automation of cartographic generalisation. This paper explores this potenti...
Article
Full-text available
Spatial analysis and pattern recognition with vector spatial data is particularly useful to enrich raw data. In road networks, for instance, there are many patterns and structures that are implicit with only road line features, among which highway interchange appeared very complex to recognize with vector-based techniques. The goal is to find the r...
Article
Mapping applications display multi-scale maps where zooming in and out triggers the display of different maps at different scales. Multi-scale maps strongly augmented the potential uses of maps, compared to the traditional single-scaled paper maps. But the exploration of the multi-scale maps can be cognitively difficult for users because the conten...
Article
Full-text available
Les cartes tactiles photoréalistes sont un des outils mobilisés par les personnes en situation de déficience visuelle pour appréhender leur environnement urbain proche, notamment dans le cadre de la mobilité, pour la traversée de carrefours par exemple. Ces cartes sont aujourd’hui principalement fabriquées artisanalement. Dans cet article, nous pro...
Article
Full-text available
Contour lines are a key features of topographic maps as they make the comprehension of terrain more easy. But they are no longer drawn by cartographers, they are mostly automatically derived from digital terrain models. Despite real progress in this automated derivation, some specific terrain landscapes remain incorrectly depicted with such techniq...
Article
Full-text available
Automatic map generalization is a complex task that is still a research problem and requires the development of research prototypes before being usable in productive map processes. In the meantime, reproducible research principles are becoming a standard. Publishing reproducible research means that researchers share their code and their data so tha...
Article
Full-text available
The impetus induced by the development of multi-scale, multi-style maps calls for thinking our resources and protocols with greater interoperability. In the field of toponymy, this requires, in particular, thinking of categories and their structuring with more granularity. Assuming that typography, as a device for visualizing toponyms, is a tool wh...
Article
The automation of map generalization has been keeping researchers in cartography busy for years. Particularly great progress was made in the late 90s with the use of the multi-agent paradigm. Although the current use of automatic processes in some national mapping agencies is a great achievement, there are still many unsolved issues and research se...
Article
Dans un contexte où le vandalisme de l’information géographique volontaire constitue une réelle menace pour la qualité des données, cet article propose une technique permettant de le détecter. Tout d’abord, nous examinons les différentes définitions du vandalisme, mettant en avant la complexité de cette notion. Une étude des cas déjà avérés de vand...
Article
This paper aims to qualify the behaviour of contributors to OpenStreetMap (OSM), a volunteered geographic information (VGI) project, through a multigraph approach. The main purpose is to reproduce contributor's interactions in a more comprehensive way. First, we define a multigraph that combines existing spatial collaboration networks from the lite...
Conference Paper
Full-text available
Dans un contexte où le vandalisme de l'information géographique volontaire constitue une réelle menace pour la qualité des données, cet article propose d'explo-rer les diérentes techniques permettant de le détecter. Tout d'abord, nous tâchons d'examiner les diérentes définitions du vandalisme, mettant en avant la complexité de cette notion. Puis, n...
Conference Paper
Full-text available
Vandalism is a phenomenon that has affected by now the digital domain, in particular in the context of Volunteered Geographic Information projects. This paper aims at proposing a methodology to detect vandalism in the OpenStreetMap project. First, an analysis of related works sheds light on the lack of consensus when it comes to defining vandalism...
Article
Tactile maps are essential tools for visually impaired people to comprehend space and to support the simple pedestrian trips made difficult by their disability. Tactile maps are created manually and printed by specialists, and it takes a large amount of time to create a new one, which prevents using them on demand for everyday use. As a consequence...
Conference Paper
Full-text available
This talk introduces the results of MapMuxing, a collaborative project aiming at providing cartographic multiplexing techniques for crisis management. The project grouped researchers in geovisualisation, computer-human interaction and risk geography to better understand visualisation needs and design cartographic continuum and multiplexing techniqu...
Article
Full-text available
Map users may have issues to achieve multi-scale navigation tasks, as cartographic objects may have various representations across scales. We assume that adding intermediate representations could be one way to reduce the differences between existing representations, and to ease the transitions across scales. We consider an existing multiscale map o...
Article
Full-text available
Geoportals and geovisualization tools provide to users various cartographic abstractions that describe differently a geographical space. Our purpose is to be able to design cartographic continuums, i.e. a set of in-between maps allowing users to navigate between two topographic styles. This paper addresses the problem of the interpolation between t...
Article
Full-text available
Label placement is a tedious task in map design, and its automation has long been a goal for researchers in cartography, but also in computational geometry. Methods that search for an optimal or nearly optimal solution that satisfies a set of constraints, such as label overlapping, have been proposed in the literature. Most of these methods mainly...
Conference Paper
Full-text available
Modéliser les interactions sociales au sein de projets de cartographie volontaire et citoyenne nécessite de définir ce qui relie les contributeurs entre eux dans le temps et l'espace. Dans un souci de réalisme, plu-tôt que d'étudier un seul type de relation, nous choisissons de construire un réseau social multi-couche contenant différents types d'i...
Technical Report
Full-text available
Cartographic generalization is a highly local and contextual process where decisions are taken locally to better adjust the transformations used to the local geography. Thus, carto-graphic generalization fits well with the multi-agents paradigm that promotes decentralized and autonomous decision-making. The past years of research in cartographic ge...
Article
Automatic map generalization requires the use of computationally intensive processes often unable to deal with large datasets. Distributing the generalization process is the only way to make them scalable and usable in practice. But map generalization is a highly contextual process, and the surroundings of a generalized map feature needs to be know...
Conference Paper
Full-text available
To enable smooth zooming, we propose a method to continuously generalize buildings from a given start map to a smaller-scale goal map, where there are only built-up area polygons instead of individual building polygons. We name the buildings on the start map original buildings. For an intermediate scale, we aggregate the original buildings that wil...
Conference Paper
Modelling social interactions in volunteered geographic information projects requires defining what binds contributors together. In order to be as realistic as possible , instead of choosing one social aspect to study, we choose to build a multi-layered social network that contains several types of interaction between VGI contributors. The analysis...
Chapter
Full-text available
Today almost any kind of User Generated Content (UGC) can be situated within a geographic context. Volunteered Geographic Information (VGI) can include many types of UGC, such as georeferenced photographs, social media and text, geographic data themselves, etc. There are legal, privacy and ethical issues raised by VGI, and at present these are not...
Chapter
Full-text available
The most common way to use geographic information is to make maps. With the ever growing amount of Volunteered Geographic Information (VGI), we have the opportunity to make many maps, but only automatic cartography (generalisation, stylisation, text placement) can handle such an amount of data with very frequent updates. This chapter reviews the re...
Conference Paper
Full-text available
Label placement is a tedious task in map design, and its automation has long been a goal for researchers in cartography, but also in computational geometry. Methods that search for an optimal or nearly optimal solution that satisfies a set of constraints, such as label overlapping, have been proposed in the literature. Most of these methods mainly...
Conference Paper
Full-text available
Automatic map generalization requires the use of computationally intensive processes often unable to deal with large datasets. Distributing the generalization process is the only way to make them scalable and usable in practice. But map generalization is a highly contextual process, and the surroundings of a generalized map feature needs to be know...
Conference Paper
Full-text available
Map users may have issues to achieve multi-scale navigation tasks, as cartographic objects may have various representations across scales. We assume that adding intermediate representations could be one way to reduce the differences between existing representations, and to ease the transitions across scales. We consider an existing multi-scale map...
Conference Paper
Full-text available
Geoportals and geovisualization tools provide to users various cartographic abstractions that describe differently a geographical space. Our purpose is to be able to design cartographic continuums, i.e. a set of in-between maps allowing users to navigate between two topographic styles. This paper addresses the problem of the interpolation between t...
Conference Paper
Full-text available
Geovisualization applications that allow the navigation between maps at different scales while zooming in and out often provide no smooth transition between the individual building level of abstraction and the representation of whole urban areas as polygons. In order to reduce the cognitive load of the user, we seek to add intermediate zoom levels...
Chapter
OpenStreetMap data comprise of very detailed (e.g. zebra crossing) and quite rough features (e.g. built-up area). But making large scale maps from data with inconsistent level of detail often blurs map comprehension. This paper explores the automatic harmonization of OpenStreetMap data for large scale maps, i.e. the process that transforms rough ob...
Article
Full-text available
Among approaches for automated generalization of vector data, we focus on the multi-agent paradigm: cartographic objects are modeled as agents (autonomous objects) that apply generalization algorithms to themselves to satisfy cartographic constraints. Several agent levels are considered, for example, individual agents, such as a building, and agent...
Article
Full-text available
With the development of location-aware devices and the success and high use of Web 2.0 techniques, citizens are able to act as sensors by contributing geographic information. In this context, data quality is an important aspect that should be taken into account when using this source of data for different purposes. The goal of the paper is to analy...
Article
Full-text available
Whatever the data source, or the capture process, the creation of a building footprint in a geographical dataset is error prone. Building footprints are designed with square angles, but once in a geographical dataset, the angles may not be exactly square. The almost-square angles blur the legibility of the footprints when displayed on maps, but mig...
Article
The clutter effect occurs when there is an excessive amount of information in a map or when this information is disorganized. Measurement of clutter is essential to improve the quality of outputs produced using automated cartographic systems. This paper reviews some existing methods for measuring clutter from different research communities, highlig...