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A Study of Blind Drawing Practice: A Study of Blind Drawing Practice: Creating Graphical Information Creating Graphical Information Without the Visual ChannelWithout the Visual Channel
Hesham M. Kamel
James A. Landay
Group for User Interface ResearchEECS DepartmentUniversity of California, Berkeley
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Visual Communication by Blind PeopleVisual Communication by Blind People
(Kurze, 1996, figure 5)
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Presentation OverviewPresentation Overview
Problems with GUIsCreating vs. accessing graphical dataStudy of blind drawing practiceRequired mechanisms for blind drawingThe grid-based model for drawingDemonstration of drawing with IC2DConclusion
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Problems with GUIsProblems with GUIs
Rely entirely on visual feedback & direct manipulation
Graphical elements hinder screen readers Warnings
– “…enabling technologies for the sighted have become disabling technologies for the visually-impaired” (Pun, Roth, & Petrucci, 1998)
– New interfaces threaten effectiveness of screen readers (Boyd, Boyd, & Vanderheiden, 1990)
Goal of screen reader developers– develop meaningful non-visual representation
of picture-based interfaces
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Problems with Drawing Tool UIsProblems with Drawing Tool UIs
Graphical user interfaces– imagine drawing with the monitor off
• where is the cursor?• what’s on the screen?• how do I get back to where I was?
Haptic user interfaces– hard to carry– expensive
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Accessing Graphical DataAccessing Graphical Data
Relies on the method of output – audio-haptic
• Talking Fingertip (Vanderheiden, 1996)
– non-speech audio • (Alty & Rigas, 1998)
– speech and non-speech audio • Mercator (Mynatt, 1995)
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Creating Graphical DataCreating Graphical Data
Relies on the method of input & requires feedback – tactile freehand drawing
• Sewell line drawing kit (Millar, 1975)• thermo-pen and heat sensitive paper,
speech (Kurze, 1996)
Do tactile freehand drawing tools provide enough feedback?
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Study of Blind Drawing PracticeStudy of Blind Drawing Practice
Used the Sewell Raised Line Drawing Kit5 participants: 3 partially & 2 totally blind
Drawing Task Evaluation Metrics
Uppercase “D” Curvature, closure
2 greater-than signs Angle, length consistency
2 squares Equal in size, square
Any drawing Match user’s intentions
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MethodologyMethodology
Emphasized testing of tool, not skillsNo prior experience with drawing toolEqual amount of familiarization timeNo physical model was provided to
participants
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Testing Curvature and ClosureTesting Curvature and Closure
“The curvature is not what I had in mind.
I wanted it to look like a half tear drop.”
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Importance of FeedbackImportance of Feedback
Improper closure by 3/5 participants Via touching or looking at the figures
participants could assess performance
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Testing Length, Angle and ClosureTesting Length, Angle and Closure
Measurement by counting
Measurement betweenthumb & pinky
Measurement using knuckles
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Self-directed DrawingSelf-directed Drawing
“It looks a little sloppier than what I had in mind.” “The feet are where they should not be”
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Findings of StudyFindings of Study
Drawing requires mechanisms for– assessing curvature – finding relative and absolute locations– measuring distances– determining angles
There are a number of strategies for determining line length
3/5 participants were very happy with their self-directed drawings
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Presentation RecapPresentation Recap
Problems with GUIsCreating vs. accessing graphical dataStudy of blind drawing practiceRequired mechanisms for blind drawingThe grid-based model for drawingDemonstration of drawing with IC2DConclusion
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Grid-based Drawing ModelGrid-based Drawing Model
Based on telephone keypad– known by most blind individuals– nine fixed screen cells– each cell is a unique point of
reference & can be selected• equivalent to point & click
The grid supports– finding relative and absolute
locations– measuring distances– determining common angles
1 2 3
4 5 6
7 8 9
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IC2D: A Grid-based Drawing ProgramIC2D: A Grid-based Drawing Program
For both drawing by the blind & communicating drawings by sighted users
Uses grid for navigation, selection & feedback
Two ways to navigate– directional keys or numbers 1-9
Voice & non-speech feedback– blind users accustomed to
screen readers
car created with helpof sighted user –
self describes its “parts”
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Grid RecursionGrid Recursion
Allows more precise point selections Resolution of 27 x 27 cells
– permits drawing objects at different scale Objects drawn at full screen resolution
– example, the right arrow
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Example: Drawing a CircuitExample: Drawing a Circuit
DemonstrationDemonstration
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Example: My HouseExample: My House
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Pilot EvaluationPilot Evaluation
Tested with two blind users– both blind from birth
Three drawing tasks after a 25 min. tutorial
Results encouraging– car drawn in ~13 min.
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ConclusionConclusion
Audio feedback can work for drawing Grid-based model allows
– finding relative and absolute locations– measuring distances– determining angles– currently limited for assessing curvature
The recursive grid is a general technique for graphical interaction
Better drawing tools open graphical communication between blind and sighted
Blindness is not an excuse, it is a challenge
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For More InformationFor More Information
http://guir.berkeley.edu/ic2d
http://guir.berkeley.edu