title: Image Sensor Nonuniformity Correction by a Scene-Based Maximum Likelihood Approach
creator: Geese, Marc
subject: ddc-530
subject: 530 Physics
description: Image sensors come with a spatial inhomogeneity, known as Fixed Pattern Noise or image sensor nonuniformity, which degrades the image quality. These nonuniformities are regarded as the systematic errors of the image sensor, however, they change with the sensor temperature and with time. This makes laboratory calibrations unsatisfying. Scene based nonuniformity correction methods are therefore necessary to correct for these sensor errors.   In this thesis, a new maximum likelihood estimation method is developed that estimates a sensor’s nonuniformities from a given set of input images. The method follows a rigorous mathematical derivation that exploits the available sensor statistics and uses only well-motivated assumptions. While previous methods need to optimize a free parameter, the new method’s parameters are defined by the statistics of the input data. Furthermore, the new method reaches a better performance than the previous methods. Specialized developments that include a row- or column-wise and a combined estimation of the nonuniformity parameters are introduced as well and are of relevance for typical industrial applications.   Finally it is shown that the previous methods can be regarded as simplifications of the newly developed method. This deliberation gives a new view onto the problem of scene based nonuniformity estimation and allows to select the best method for a given application. 
date: 2013
type: Dissertation
type: info:eu-repo/semantics/doctoralThesis
type: NonPeerReviewed
format: application/pdf
identifier: https://archiv.ub.uni-heidelberg.de/volltextserverhttps://archiv.ub.uni-heidelberg.de/volltextserver/14391/1/PhD%20%5BMarc%20Geese%5D_kompressed.pdf
format: application/pdf
identifier: https://archiv.ub.uni-heidelberg.de/volltextserverhttps://archiv.ub.uni-heidelberg.de/volltextserver/14391/3/geese2013.pdf
identifier: DOI:10.11588/heidok.00014391
identifier: urn:nbn:de:bsz:16-heidok-143919
identifier:   Geese, Marc  (2013) Image Sensor Nonuniformity Correction by a Scene-Based Maximum Likelihood Approach.  [Dissertation]     
relation: https://archiv.ub.uni-heidelberg.de/volltextserver/14391/
rights: info:eu-repo/semantics/openAccess
rights: http://archiv.ub.uni-heidelberg.de/volltextserver/help/license_urhg.html
language: eng