Chapter Three: 3-D Data Acquisition --- Stereoscopic Vision and Range Finders
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Chapter 3: Acquisition of 3-D Data
Representation of 3D data range images
image format
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shaded image
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Chapter 3: Acquisition of 3-D Data
Non-Touching Methods • Passive methods:
shading and texture analysis stereo cameras motion analysis lens focusing • Active methods: photometric stereo structured lights radar sensing
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Chapter 3: Acquisition of 3-D Data
A Stereo Vision System
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Chapter 3: Acquisition of 3-D Data
Main Topics • Principle of stereo vision • Methods of correspondence searching • Range finders based on laser scanning
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Chapter 3: Acquisition of 3-D Data
Visual System of Human Brain
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Chapter 3: Acquisition of 3-D Data
Stereograms: Random Dots
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Chapter 3: Acquisition of 3-D Data
Stereograms: Recovered Depth
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Chapter 3: Acquisition of 3-D Data
Stereoscopic Viewing
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Chapter 3: Acquisition of 3-D Data
A Stereo Vision System
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Chapter 3: Acquisition of 3-D Data
Problem Statements
Compute 3-D coordinates for a point in space from its image coordinates in two images taken with a stereo vision system.
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Chapter 3: Acquisition of 3-D Data
Definition of Coordinate Systems
Object-centered system
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Chapter 3: Acquisition of 3-D Data
Definition of Coordinate Systems
Camera head system
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Chapter 3: Acquisition of 3-D Data
Definition of Coordinate Systems
Po
Computation based on triangulation principle
R
' Rx
xl
CL
O'
' Ry
r
U
OL
W V
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Chapter 3: Acquisition of 3-D Data
Epipolar Constraints
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Chapter 3: Acquisition of 3-D Data
A Depth Image from Stereo
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Chapter 3: Acquisition of 3-D Data
Correspondence Problem
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Chapter 3: Acquisition of 3-D Data
Ambiguity in Correspondence
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Chapter 3: Acquisition of 3-D Data
Correlation-Based Correspondence
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Chapter 3: Acquisition of 3-D Data
Peak Detection
sharp peak
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smooth peak
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Chapter 3: Acquisition of 3-D Data
Aperture Problem
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Chapter 3: Acquisition of 3-D Data
Feature Matching by Relaxation
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Chapter 3: Acquisition of 3-D Data
A Range Finder System
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Chapter 3: Acquisition of 3-D Data
Laser slit images
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Chapter 3: Acquisition of 3-D Data
Laser Scanner
A laser slit and a camera
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Chapter 3: Acquisition of 3-D Data
Laser Scanner
Geometrical relationship
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Chapter 3: Acquisition of 3-D Data
Laser Scanner: Vivid 700
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Chapter 3: Acquisition of 3-D Data
Laser Scanner: Fast Scan
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Chapter 3: Acquisition of 3-D Data
Laser Scanner: Cyrax 2500
A portable laser scanner produced origianlly by Cyra, Canada, and now by Leica, Switzerland
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Chapter 3: Acquisition of 3-D Data
A portable laser scanner produced origianlly by Cyra, Canada, and now by Leica, Switzerland
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Chapter 3: Acquisition of 3-D Data
Time-of-Flight Imaging Radar
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A Video Clip from Cyra
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