from open geographical data to tangible maps: improving the accessibility of maps for visually...

From open geographical data to tangible maps:

improving the accessibility of maps for visually

impaired people

Julie Ducasse, Marc Macé, Christophe Jouffrais

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http://www.irit.fr/accessimap/

http://www.cherchonspourvoir.org/fr/

ACCESSIBILITY OF MAPS

• 285 millions of visually impaired people

• Maps and graphics are inherently inaccessible

• But necessary:

• For educational purposes

Orientation & Mobility

Geography

• For day-to-day life

Preparing an itinerary

Discovering a new city

General knowledge

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A raised-line map

INTERACTIVE MAPS

Brock et al. Interactivity Improves Usability of Geographic Maps for Visually Impaired

People. in Human-Computer Interaction

Touch the map ! 1

• Touch sensitive devices with a tactile overlay : audio-

tactile maps

Can be explored with two hands

Are affordable

More usable than tactile maps

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INTERACTIVE MAPS

How to automate the production of

interactive tactile maps ?

How to enable a more dynamic exploration

and a more autonomous access ? 4

DEVELOPMENT OF A WEB-BASED

AUTHORING EDITOR FOR THE

PRODUCTION OF TACTILE MAPS 5

RELATED WORK & MOTIVATION

Producting tactile maps is time-consuming process

Two approaches to automate the production:

1/ Image recognition algorithms

• Input: a still image of a 2D map / a hand-drawn map

• Text detection, graphic simplification, etc.

2/ Adaptation of GIS data

• Based on tactile graphics guidelines

• Simplification of existing data

Output: digital file (SVG) + tactile overlay

Limitations

• How to adapt the symbols to the user’s needs ?

• How to choose the interactions ?

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FUNCTIONALITIES

1/ Selecting the original file (SVG or geographic location)

2/ Choosing the symbols

3/ Adding new points, lines, circles or polygons

4/ Editing or adding labels

5/ Selecting a layer of information

6/ Selecting or adding different pieces of information

7/ Specifying the interaction for each element

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EXAMPLE

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EXAMPLE

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BENEFITS AND DRAWBACKS

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Possible to produce interactive tactile maps

• From an SVG file

• From OpenStreetMap

Not fully automatic (editing the symbols, printing the tactile

map, etc.)

Limits the user’s autonomy

Non editable

DESIGN AND EVALUATION OF A

TABLETOP TANGIBLE INTERFACE

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MOTIVATIONS

Providing visually impaired users with

an autonomous and instantaneous access

to interactive maps

and dynamic “visualization”.

To enhance the number of functionalities

(annotation, exploration, distance computing, etc.)

To promptly build a simple map without assistance

Zoom, pan, add or remove objects depending on the

information the user want to access

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TANGIBLE INTERACTION

Tangible interface: when a physical representation is coupled

with a digital representation

ReacTable 1 Clutching at straws 2

1 Jordà et al.,“The reacTable : Exploring the Synergy between …” 2 McGookin et al., “Clutching at Straws: … .” CHI ’10

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CONSTRUCTION AND EXPLORATION OF TANGIBLE MAPS

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Tangible Reel

CONSTRUCTION AND EXPLORATION OF TANGIBLE MAPS

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Tangible Reel

EVALUATION

8 visually impaired users

1/ Construction of 4 maps of increasing complexity

2/ For each map, 3 questions: what are the names of the

start and end points of the line xx ?

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RESULTS

Number of success and failures

27 maps out of 32

were correctly reconstructed

Map 6: 2 minutes

Map 8 & 10: 3.5 minutes

Map 12: 4.5 minutes

90% of the answers to the exploration questions were correct 17

283 Tangible Reels

out of 288

were correctly placed

FUTURE WORK

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TACTILE GRAPHICS

Extending our work to tactile graphics:

Bar charts

Geometric drawings

Organigrams

Schemas

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Dynamic exploration: zoom, pan, etc.