Real-time focus range sensor
- 19 November 2002
- conference paper
- Published by Institute of Electrical and Electronics Engineers (IEEE)
- p. 995-1001
- https://doi.org/10.1109/iccv.1995.466826
Abstract
Structures of dynamic scenes can only be recovered using a real-time range sensor. Depth-from-defocus offers a direct solution to fast and dense range estimation. It is computationally efficient as it circumvents the correspondence problem faced by stereo and feature tracking in structure-from-motion. However, accurate depth estimation requires theoretical and practical solutions to a variety of problems including the recovery of textureless surfaces, precise blur estimation, and magnification variations caused by defocusing. Both textured and textureless surfaces are recovered using an illumination pattern that is projected via the same optical path used to acquire images. The illumination pattern is optimized to ensure maximum accuracy and spatial resolution in the computed depth. The relative blurring in two images is computed using a narrow-band linear operator that is designed by considering all the optical, sensing and computational elements of the depth-from-defocus system. Defocus-invariant magnification is achieved by the use of an additional aperture in the imaging optics. A prototype focus range sensor has been developed that produces up to 512/spl times/480 depth estimates at 30 Hz with an accuracy better than 0.3%. Several experimental results are included to demonstrate the performance of the sensor.<>Keywords
This publication has 14 references indexed in Scilit:
- Pyramid based depth from focusPublished by Institute of Electrical and Electronics Engineers (IEEE) ,2003
- Robust focus rangingPublished by Institute of Electrical and Electronics Engineers (IEEE) ,2003
- Microscopic shape from focus using active illuminationPublished by Institute of Electrical and Electronics Engineers (IEEE) ,2002
- A matrix based method for determining depth from focusPublished by Institute of Electrical and Electronics Engineers (IEEE) ,2002
- Depth and thermal stability of dry etch damage in GaN Schottky diodesApplied Physics Letters, 1999
- Range estimation from focus using a non-frontal imaging cameraInternational Journal of Computer Vision, 1996
- Simple range cameras based on focal errorJournal of the Optical Society of America A, 1994
- Shape from focusPublished by Institute of Electrical and Electronics Engineers (IEEE) ,1994
- FocusingInternational Journal of Computer Vision, 1988
- A New Sense for Depth of FieldPublished by Institute of Electrical and Electronics Engineers (IEEE) ,1987