Aston Research Explorer
Thomson, Robert C. (1991). Petrographic image analysis and understanding. PhD thesis, Aston University.
|PDF (Petrographic image analysis and understanding)|
This study considers the application of image analysis in petrography and investigates the possibilities for advancing existing techniques by introducing feature extraction and analysis capabilities of a higher level than those currently employed. The aim is to construct relevant, useful descriptions of crystal form and inter-crystal relations in polycrystalline igneous rock sections. Such descriptions cannot be derived until the `ownership' of boundaries between adjacent crystals has been established: this is the fundamental problem of crystal boundary assignment. An analysis of this problem establishes key image features which reveal boundary ownership; a set of explicit analysis rules is presented. A petrographic image analysis scheme based on these principles is outlined and the implementation of key components of the scheme considered. An algorithm for the extraction and symbolic representation of image structural information is developed. A new multiscale analysis algorithm which produces a hierarchical description of the linear and near-linear structure on a contour is presented in detail. Novel techniques for symmetry analysis are developed. The analyses considered contribute both to the solution of the boundary assignment problem and to the construction of geologically useful descriptions of crystal form. The analysis scheme which is developed employs grouping principles such as collinearity, parallelism, symmetry and continuity, so providing a link between this study and more general work in perceptual grouping and intermediate level computer vision. Consequently, the techniques developed in this study may be expected to find wider application beyond the petrographic domain.
|Item Type:||Thesis (PhD)|
|Additional Information:||Department: Geological Sciences If you have discovered material in AURA which is unlawful e.g. breaches copyright, (either theirs or that of a third party) or any other law, including but not limited to those relating to patent, trademark, confidentiality, data protection, obscenity, defamation, libel, then please read our Takedown Policy and contact the service immediately.|
|Uncontrolled Keywords:||image analysis, image understanding, igneous petrography, shape analysis, symmetry analysis|
|Divisions:||Schools_of_Study > Life & Health Sciences|
|Deposited By:||Mr Mandev Padda|
|Deposited On:||22 Feb 2011 14:47|
|Last Modified:||18 Dec 2014 04:47|
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