ISBN-13: 9783639184860 / Angielski / Miękka / 2009 / 204 str.
ISBN-13: 9783639184860 / Angielski / Miękka / 2009 / 204 str.
Stained glass has been an important medium for the illustration of European culture and history and is still used today in architecture and the decorate arts. Heritage conservators are interested in using digital images in the analysis of stained glasses. Stained glass images differ from natural images in many aspects. Their colour is generated by transmitted, rather than reflected light. In many cases the background is partially visible through the glass, typically showing trees, sky, etc. Images of stained glass taken with external illumination very often contain shadows, cast by structures such as protective bars and grilles. The physical structures producing the shadows are often irremovable, because they are difficult to access or constitute structural elements of the window. It is thus necessary to provide a suitable set of image processing tools to remove background and shadows from the digital images. This book introduces systematic procedures to calculate statistics of stained glass on digital images and develops novel algorithms for segmentation, feature extraction, and removal of image defects including non-uniform illumination, shadows of bars and grills and background.