Today’s class A Taxonomy A taxonomy Unstructured light Space-time stereo

Today’s class A Taxonomy A taxonomy Unstructured light Space-time stereo www.phwiki.com

Today’s class A Taxonomy A taxonomy Unstructured light Space-time stereo

Manning, Marty, Morning and Afternoon On-Air Personality has reference to this Academic Journal, PHwiki organized this Journal Structured light in addition to active ranging techniques Class 8 Geometric Computer Vision course schedule (tentative) Today’s class unstructured light structured light time-of-flight (some slides from Szymon Rusinkiewicz, Brian Curless)

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A Taxonomy A taxonomy Unstructured light project texture to disambiguate stereo

Space-time stereo Davis, Ramamoothi, Rusinkiewicz, CVPR’03 Space-time stereo Davis, Ramamoothi, Rusinkiewicz, CVPR’03 Space-time stereo Zhang, Curless in addition to Seitz, CVPR’03

Space-time stereo results Zhang, Curless in addition to Seitz, CVPR’03 Triangulation Triangulation: Moving the Camera in addition to Illumination Moving independently leads to problems with focus, resolution Most scanners mount camera in addition to light source rigidly, move them as a unit

Triangulation: Moving the Camera in addition to Illumination Triangulation: Moving the Camera in addition to Illumination (Rioux et al. 87) Triangulation: Extending to 3D Possibility 1: add another mirror (flying spot) Possibility 2: project a stripe, not a dot Object

Triangulation Scanner Issues Accuracy proportional to working volume (typical is ~1000:1) Scales down to small working volume (e.g. 5 cm. working volume, 50 m. accuracy) Does not scale up (baseline too large ) Two-line-of-sight problem (shadowing from either camera or laser) Triangulation angle: non-uni as long as m resolution if too small, shadowing if too big (useful range: 15-30) Triangulation Scanner Issues Material properties (dark, specular) Subsurface scattering Laser speckle Edge curl Texture embossing

Space-time analysis Curless ‘95 Space-time analysis Curless ‘95 Projector as camera

Multi-Stripe Triangulation To go faster, project multiple stripes But which stripe is which Answer 1: assume surface continuity e.g. Eyetronics’ ShapeCam Real-time system Koninckx in addition to Van Gool Real-time scanning system Rusinckiewicz et al. Siggraph02 Szymon Rusinckiewicz talk Friday 20/11 at 11:15 in ETZ E9 (in context of PhD defense Thibaut Weise, also 20/11 at 15:00 in ETF C109)

Manning, Marty KESZ-FM Morning and Afternoon On-Air Personality www.phwiki.com

In-h in addition to modeling Weise et al. CVPR08 Multi-Stripe Triangulation To go faster, project multiple stripes But which stripe is which Answer 2: colored stripes (or dots) Multi-Stripe Triangulation To go faster, project multiple stripes But which stripe is which Answer 3: time-coded stripes

Time-Coded Light Patterns Assign each stripe a unique illumination code over time [Posdamer 82] Space Time An idea as long as a project Bouget in addition to Perona, ICCV’98 Pulsed Time of Flight Basic idea: send out pulse of light (usually laser), time how long it takes to return

Depth from focus/defocus Nayar’95 Next class: structure from motion

Manning, Marty Morning and Afternoon On-Air Personality

Manning, Marty is from United States and they belong to KESZ-FM and they are from  Phoenix, United States got related to this Particular Journal. and Manning, Marty deal with the subjects like Music

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