polyzoom: multiscale and multifocus exploration in 2d visual spaces

PolyZoom: Multiscale and Multifocus Exploration

in 2D Visual Spaces

Waqas Javed, Sohaib Ghani, Niklas ElmqvistPurdue UniversityWest Lafayette, IN

USA

Presented By: Sohaib Ghani

ACM CHI 2012May 5-8, 2012 ▪ Austin, Texas

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Where is Central Park???

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Where am I ???

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I foundCentral Park!!!

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Outline

• Motivation• Demo• Related Work• The PolyZoom Technique– Design Decisions– Layout– PolyZoom: System

• User Studies• Conclusion

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Motivation

• Multiscale visual space – Example: Google Maps – geospatial dataset

• Large (entire world) and two-dimensional• Multiscale (different data at different levels of detail)

• Navigation in such visual spaces is difficult – Desert fog– Multifocus interaction

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• PolyZoom is a multiscale multifocus technique for navigating in 2D visual spaces– Allows users to iteratively build a hierarchy of focus regions– Allows maintaining awareness of multiple scales of the visual space

• [Video]

PolyZoom

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Related Work

• Common Navigation Techniques– Scrolling (Igarashi and Hinckley 2000)

– Pan & Zoom ( Furnas and Bederson 2005)

– Overview + Detail (Hornbæk and Frøkjær 2001)

– Focus + Context (Furnas 1986)

• Multifocus Interaction– Split-screen techniques (Shoemaker and Gutwin 2007)

– Stack zooming (Javed and Elmqvist 2010)

• Multiscale Navigation– Pad (Perlin and Fox 1993)

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PolyZoom: Design Goals

• Multiscale awareness• Multifocus awareness• No distortion• No overlap

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PolyZoom: Layout• Layout• Viewport size management• Correlation graphics

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PolyZoom: System

• Web-based implementation– ActionScript3, Flash, and HTML5

• Google Maps dataset, NASA Universe, a Lunar dataset, and a Martian dataset

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User Studies

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Study 1: Multiscale Visual Search

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Study 1: Multiscale Visual Search

• Participants: 12• Navigation Techniques: 2– P – PolyZoom– S – Simple Pan & Zoom

• Hierarchy Levels L : 3 (3,4,5) • Repetitions: 4• Task

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Study 1: Multiscale Visual Search• Hypothesis: P will be faster than S• Result: significant main effect of Technique T on completion time • Also significant main effect of Hierarchy Level L on completion time • Completion time was roughly linear with number of hierarchy levels• Levels were significantly different with completion times ordered

3 < 4 < 5 (Tukey HSD, p < .05)• No significant interaction between T and L

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Study 2: Multifocus Comparison

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Study 2: Multifocus Comparison

• Participants: 12• Navigation Techniques: 2– P – PolyZoom– S – Simple Pan & Zoom

• Discovery Order D : 5 (1,2,3,4,5) • Repetitions: 2• Task

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Study 2: Multifocus Comparison• Hypothesis: P will be faster than S• Result: significant main effect of technique T on completion time • Discovery order D had a significant main effect on completion time

• Roughly linear (as expected)• Pairwise differences between orders were significant (Tukey HSD, p < .05)

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Subjective Ratings• Differences in ratings significant (Friedman test, p < .05)

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PolyZoom for 20 Years of UIST

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Conclusion

• Design of a multiscale and multifocus interaction technique called PolyZoom

• Evaluation with 2 user studies– Study 1 for multiscale visual search– Study 2 for multifocus comparisons

• PolyZoom performs better than pan & zoom

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Thank You!

Contact Information:Sohaib GhaniPurdue University, West Lafayette, IN, USA

E-mail: sghani@purdue.edu

http://engineering.purdue.edu/pivot/

Online demo available:http://web.ics.purdue.edu/~wjaved/projects/stackZoom/

Partially funded by NSF Grant #1123108.