Fusion of Time-of-Flight Depth and Stereo for High
Accuracy Depth Maps
Reporter:鄒嘉恆Date:2009/11/17
Introduction
They provide real time depth estimates by combine stereo and Time-of-flight.
Outline
MotivationMulti-sensor calibration
Geometric calibrationPhotometric calibrationCalibration verification
Sensor fusionExperimental resultsConclusion
Motivation
Problem:Laser scanner are too slow for real time use.Stereo fails on textureless scenes.TOF is low resolution, noisy, and poorly calibrated.
Multi-sensor setup
SR3000:176x144Operational range up to 7 meters
2 CCD stereo cameraslimit the calibration range from 1m to 1.4m
Multi-sensor calibration
Geometric calibration
Multi-sensor calibration
Photometric calibration
Multi-sensor calibration
Calibration verification-plane experiment
Multi-sensor calibration
Calibration verification-plane experiment
Multi-sensor calibration
Calibration verification-plane experiment
Calibration verification-box experiment
Sensor fusionfd : the local evidence for node i
fs : a symmetric function measures the smoothness assumption about the scene
fr : the additional local evidence based on the measurement from the TOF sensor.
Experimental results
Using TOF(A)local method(B)local method with LUT(C)global method(D)global method with LUT
Using stereo(E)local method(F)global method
(G)local fusion method(H)global fusion method
Experimental results
Experimental results
Conclusion
They present a simple and effective calibration method to improve the performance of time-of-flight sensors.
Their method can achieve an absolute accuracy of about 5mm over a range of one meter.
The fusion results reduce the over-all error by 50%.