Estimation of camera parameters from stereo pairs with no external control information

dc.contributor.author	Καλησπεράκης, Ηλίας	el
dc.contributor.author	Καρράς, Γιώργος	el
dc.contributor.author	Πέτσα, Έλλη	el
dc.date.accessioned	2015-01-28T21:13:18Z
dc.date.available	2015-01-28T21:13:18Z
dc.date.issued	2015-01-28
dc.identifier.uri	http://hdl.handle.net/11400/4986
dc.rights	Αναφορά Δημιουργού-Μη Εμπορική Χρήση-Όχι Παράγωγα Έργα 3.0 Ηνωμένες Πολιτείες	*
dc.rights.uri	http://creativecommons.org/licenses/by-nc-nd/3.0/us/	*
dc.subject	Calibration
dc.subject	Orientation
dc.subject	Bundle
dc.subject	Lens Distortion
dc.subject	Precision
dc.subject	Βαθμονόμηση
dc.subject	Προσανατολισμός
dc.subject	Δέσμη
dc.subject	Φακός παραμόρφωσης
dc.subject	Ακρίβεια
dc.title	Estimation of camera parameters from stereo pairs with no external control information	en
heal.type	conferenceItem
heal.classification	Technology
heal.classification	Photogrammetry
heal.classification	Τεχνολογία
heal.classification	Φωτογραμμετρία
heal.classificationURI	http://id.loc.gov/authorities/subjects/sh85133147
heal.classificationURI	http://skos.um.es/unescothes/C02980
heal.classificationURI	N/A-Τεχνολογία
heal.classificationURI	N/A-Φωτογραμμετρία
heal.language	en
heal.access	free
heal.recordProvider	Τ.Ε.Ι. Αθήνας, Σχολή Τεχνολογικών Εφαρμογών, Τμήμα Μηχανικών Πληροφορικής και Μηχανικών Τοπογραφίας & Γεωπληροφορικής	el
heal.publicationDate	2005-09-27
heal.bibliographicCitation	Kalisperakis, I., Karras, G. and Petsa, E. (2005). Estimation of camera parameters from stereo pairs with no external control information. Proc. XX CIPA International Symposium, Torino, 27/9- 1/10/2005, pp. 390-394. Available from: http://portal.survey.ntua.gr/main/labs/photo/staff/gkarras/Karras_Cipa_2005b.pdf	en
heal.abstract	Leaving planar rectification aside, in most practical cases of architectural photogrammetry – where mostly non-metric cameras are now used – the camera interior orientation must be known. Of course, it is infeasible to anticipate every possible case and calibrate in advance all available (including auto-focus and zoom) lenses. Therefore, tools are required for the on-the-job estimation of interior orientation parameters. This paper focuses on the simplest instances, namely when no ground control is available. To this end, there exist both single-image methods (for images with clearly defined vanishing points) as well as a multi-image approaches (self-calibra-ting bundle adjustment which, in principle, also allows estimating the camera interior parameters without exterior information). Most applications, however, still rely on the stereo pair. Thus, the question of determining camera parameters solely from point correspon-dences on two images is addressed here. Indeed, it is known that simple point homologies in uncalibrated stereo pairs can impose the epipolar constraint, expressed by the ‘fundamental matrix’ (well documented in computer vision literature), and even permit partialself-calibration. For instance, the camera constant of normal cameras – even if different for the two images – may be recovered if the principal point is assumed to be known. Several non-iterative algorithms have also been presented for computing one or two camera constants (the principal point can, too, be localized for given camera constants). The pertinent critical configurations have also been studied. In this contribution, the specific question of estimating a common camera constant is treated. After using a linear algorithm for obtaining initial values, bundle adjustment of the stereo pair is performed for the estimation of relative orientation together with the camera constant as well as radial lens distortion. Relying on extensive real data, the performance of this approach for partial self-calibration without external information is assessed against full self-calibrating bundle adjustment with control points. A comparison of the accuracy of 3D reconstructions with the two methods indicates that the investigated approach is capable of providing compar-able results. Further tests are still needed, however, focusing on issues such as proximity to critical geometries or the effect of noise.	en
heal.fullTextAvailability	true
heal.conferenceName	XX CIPA International Symposium	en
heal.conferenceItemType	full paper