3-D

cs5984: Information VisualizationChris North

Last Week• Virtual Environments

• 3-D manipulation, navigation, immersion

• Scientific Visualization• Data Flow?

• Peripheral Displays• Primary and secondary tasks, attention

Today• DeFanti, “Scientific Visualization”, pg 39• Sayle, “Rasmol”, web

» Yuying, Matt

3-D Data• Vector/Polygonal surface data

• Polygons approximate surfaces of 3D objects• Paint textures on surfaces• E.g: Rasmol, Quake

• Navigation: • Move camera• Move objects• 6 dof:

– 3 rotation– 3 translation

3-D Data• Voxel volume data

• Fully sampled contents of 3D objects• Voxel = 3D pixel; point in a 3D image• E.g: Visible Human, MRI, CaT scan

• Visible Human» slice and photograph

• MRI & CaT:» Measures tissue density at each point in space

• Navigation?

2-D:

3-D:

Slicing• Visible Human Explorer (north et al)

• Video?• Demo?

Slice and Dice

Image Segmentation• Determine physical

structures within volume• Manual• Image processing

• Generate surfaces

Image Segmentation• Voxel-Man• Hamburg University• http://www.uke.uni-hamburg.de/institute/imdm/idv/vm3dn/io_thorax.en.html

Transparency• Reduce occlusion problem• http://www.uke.uni-hamburg.de/institute/imdm/idv/vm3dn/io_xray_combined.en.html

3-D data: Digital Video• 3D: Stack 2D video frames

time

x

y

Slicing Digital Video• Red’s Nightmare video in VHE

Full overview:

time

zoom

Scene change

still

credits

motion

Pan left

Assignment• Read for Thurs: Workspaces

• Gelernter, “LifeStreams”, web» fanye, luhui

• Robertson, “Task Gallery”, web» priya, dilshad

• Read for Tues: Construction• Hibino, “InfoStill”, web

» gowri, joy

• Haeberli, “Data Flow”, web» ajay, denzil

Future• O+D vs. F+C• 2D vs. 3D

• Project presentations start in 2 weeks!• Last 2 days of class, 2 hours/class• 10 min talk (5 slides), demo, paper draft• Final paper: may 7

• CAVE tour now (torg 3050)