EVALUATIoN oF FRACTAL DIMENSIoNS FRoM BITMAp IMAGE (PART: ALGORITHMS)

KOŇAS, P.: evaluation of fractal dimensions from bitmap image (Part: Algorithms). Acta univ. agric. et silvic. Mendel. Brun., 2004, LII, No. 1, pp. 175-182 The work assembled the complex application for evaluation of main fractal characteristics from input image. New simple modifications of evaluation of positive cells according to appropriate scale were implemented. Detail description of theory for each method and description of evaluation process was included. Filtration modification (which is able to estimate the structure which belongs only to specified scale) was introduced together with volumetric modification that allows selecting of optional ratio for determination of positive cells. Also, Richardson method and Slit-Island method were converted to algorithm form. Program was compiled for processing of the following projects about influence between fractal dimensions and mechanical properties of tested materials. fractal dimension, algorithm, wood, program application Ročník LII 19 Číslo 1, 2004 175 Evaluation of fractal characteristics is usually very complicated and time-consuming activity. For our purposes we need to form automatic process of image analysis, which will be able to automatically treat the image and provide sufficient amount of information about fracture character of image. The main aim of the work is description of the main procedures and graphical user interface of application, which was compiled for that object. MATERIAL AND METHODS In the work we focused on evaluation of the base fractal characteristics of fractal geometry. We used three different methods of assembling of fractal dimensions and we added other modifications to these common methods. Box-counting method Method is based on dividing of area into regular boxes with the same length of box edge equals to δ (Ref.[2]). The length of edge depends on scale ε, whereas ε = 2−n for n ∈ Z [1] The length of edge is equal to product: