1. Set Up a Scan

  2. Scan an Image

    • Click a blue button on the FracLac panel.
    • After the scanning options are set for the first time, the currently selected scan type is displayed in red on the bottom of the FracLac panel and blue action buttons appear.
    • "Scan Current Image or Roi" analyzes the currently displayed image or roi selected on it.
    • The "Select and Scan Files" button analyzes images without opening them, using the currently selected type of scan and settings. Use this button to select multiple files at once.
    • The third blue button analyzes ROIs that have previously been stored in the Roi Manager (Analyze>Tools>Roi Manager).
  3. View and Save the Results

    • The results are displayed in the Results Table and in graphics, depending on the settings from Step 1. Several versions of the fractal dimension are provided. The columns listing the average and minimum cover DBs reflect the results for multiple origins. The smoothed DB is found from smoothing horizontal intervals from the regression line by removing successive box sizes yielding the same number of boxes. See the User's Guide for more information.

NOTE:

  • Options include type of box size series as well as other scanning features that can affect the results for different types of images. For instance, a Relative Series is calculated relative to the largest box using exact factors; thus, setting the maximum box size to 48 generates the box sizes {1,2,3,4,6,8,12,16,24,48}, whereas setting it to 49 generates {1,7,49}. Refer to the current User's Guide (2006) for more information.
  • For multifractal analyses and sliding box lacunarity analyses, certain settings, in particular the minimum resolvable box size, may need special attention.
    • If the red and green parts of the MF graph of ƒ(α) do not meet in a continuous curve or if they appear to cross over, for instance, sampling may be inappropriate. To correct this, try using a scaled series, increasing the minimum grid size in pixels, or increasing the number of box sizes.
    • For sliding box lacunarity, it is important in some cases to keep the minimum resolvable size (i.e., minimum grid size in pixels)high enough (e.g.,usually greater than 3). In addition, using a nonexhaustive scan often yields the same basic results as an exhaustive scan for preliminary quick analyses. To use a nonexhaustive scan, keep the slide factors greater than one (e.g., 5); setting the x and y slide factors to 1 does an exhaustive scan.
    • Note that the number of box sizes can affect the result, especially in a multifractal analysis. To reduce processing time in both multifractal and lacunarity analyses, it is often helpful to use a relatively small number of box sizes. Do this by setting the number of different box sizes to 10 or 20, for instance.
    • For a random mass multifractal analysis, you may need to adjust the maximum percent to 100%, ensure the number of box sizes is not too high and not too low, and ensure the minimum grid size in pixels is high enough (e.g., >5 or 10).
    • References for FracLac

      • 2005 - “Fractal Analysis of Microglial Morphology”, Karperien, Lucas, Aurel, and Jelinek in Bourgine, Kepes, and Schoenauer (eds.), poster, Proceedings of the European Complex Systems Society – Towards A Science Of Complex Systems.
      • 2004 - “Fractal Analysis Quantitates Overt and Subtle Effects of Naloxone and Lipopolysaccharide on Cultured Rat Microglia”, Karperien, Jelinek, Bossomaier, in Proceedings of Complex 2004, the 7th Asia-Pacific Conference on Complex Systems, Cairns, Australia.
      • 2004 - “Differentiating Grades of Microglia Activation with Fractal Analysis”, Jelinek, Karperien, Bossomaier, and Buchan, in Proceedings of Complex 2004, the 7th Asia-Pacific Conference on Complex Systems, Cairns, Australia.
      • 2002 - "MicroMod - an L-systems Approach to Neuron Modelling". Jelinek, Karperien, Cornforth, Cesar, and Leandro, in Sarker, McKay, Gen and Namatame (eds.), Proceedings of the Sixth Australia-Japan Joint Workshop on Intelligent and Evolutionary Systems, Canberra, Australia.