Automatic localisation of electron backscattering pattern bands from Hough transform

An important and challenging aspect of the development of a system for fully automated electron backscattering pattern (EBSP) analysis is the design of reliable digital image processing routines for automatic detection and localisation of the bands in the digitised patterns. Procedures based on the Hough transform which permit precise localisation of a large number of bands in digital EBSPs are described in detail. Special attention is paid to the analysis and post-processing of the Hough space which ensure a high insensitivity to noise and a high precision of the measured band positions. The possibilities for further improvements and extensions of the procedures are also discussed, including the possibility of extracting band width information from the Hough transform. To demonstrate these possibilities, a new procedure is outlined and shown to be capable of providing high precision estimates of the EBSP band positions and, in addition, fairly precise estimates of the band widths.MST/3672