The Library
The generation of depth maps via depth-from-defocus
Tools
Crofts, William Edward (2007) The generation of depth maps via depth-from-defocus. PhD thesis, University of Warwick.
|
PDF
WRAP_THESIS_Crofts_2007.pdf - Submitted Version - Requires a PDF viewer. Download (4Mb) | Preview |
|
Other (Email acceptance of digitisation)
FW Digitisation of your PhD thesis.msg Embargoed item. Restricted access to Repository staff only Download (4Mb) |
Official URL: http://webcat.warwick.ac.uk/record=b2242704~S1
Abstract
The principle aim of this study was to use the concept of image defocus related to feature depth in order to develop a system capable of converting a 2-dimensional greyscale image into a 3-dimensional depth map. An advantage of this concept (known as depth-from-defocus or simply DfD) over techniques such as stereo imaging is that there is no so-called ‘correspondence problem’ where the corresponding location of a feature or landmark point must be identified in each of the stereo images.
The majority – and the most successful – of previous researchers in DfD have used some variation of a ‘two-image’ technique in order to separate the contribution of the original scene features from the defocus effect. The best of those have achieved results typically in the range of 1% to 2% error in the accuracy of depth estimation. This thesis presents a single-image method of generating a high-density, highaccuracy depth map via the evaluation of the edge profiles of a projected structured light pattern. A novel technique of moving the projected pattern during the image capture stage allows the development of a 4-dimensional look-up table. This technique offers a solution to one of the last remaining problems in DfD, that of spatial variance. It also uses a technique to remove the dependence of original scene reflectance. The final solution generates a depth map of up to 240,000 spatially invariant depth estimates per scene image, with an accuracy of within ± 0.5%, over a depth range of 10 cm. The depth map is generated in a processing time of approximately 14 seconds once the images are loaded.
Item Type: | Thesis (PhD) | ||||
---|---|---|---|---|---|
Subjects: | T Technology > TR Photography | ||||
Library of Congress Subject Headings (LCSH): | Depth of field (Photography), Image processing -- Digital techniques, Images, Photographic | ||||
Official Date: | September 2007 | ||||
Dates: |
|
||||
Institution: | University of Warwick | ||||
Theses Department: | School of Engineering | ||||
Thesis Type: | PhD | ||||
Publication Status: | Unpublished | ||||
Supervisor(s)/Advisor: | Staunton, R. C. | ||||
Extent: | xiii, 250 leaves | ||||
Language: | eng |
Request changes or add full text files to a record
Repository staff actions (login required)
View Item |