COMPLEMENTARY METRICS
Convex Hull and Bounding Circle for a Neuron
The above image shows a neuron processed from a colour image to a binary contour, then the convex hull and bounding circle determined for the binary form. Binary images are required for finding the convex hull and bounding circle and other metrics based on them.
Convex Hull and Bounding Circle
The Hull and Circle Panel on the Graphics Pane
Use this panel,
found on the GRAPHICS
pane, to generate measures that complement
fractal analysis.
Set options to generate the
convex hull and
bounding circle, and
use them to assess
features such as
density and overall shape.
The options are available for
binary
but not grayscale scans. To activate them,
select a binary scan.
They are not available for
Multifractal or
Sliding Box Lacunarity
Scans.
They are designed for contours
but will work on other binary patterns.
With a binary scan selected, to skip the fractal analysis
and get only the HULL
and CIRCLE
and related metrics, set the
number of grid orientations to 0.
The options to generate the hull and circle graphics
are activated when the option to include
various METRICS
is selected.
These options draw outlines on copies of the original image
on screen or
saved to a folder.
If you are analyzing many files at once,
the drawing options will produce potentially unwieldy numbers
of new images. In this respect, they are most suitable for
full images or
single rois
on images that are currently open or
batch jobs for which the
results are being
automatically saved.
metrics - Measures based on the hull and circle
Select this option to include in the
results files various types of data based on the
bounding circle
and convex hull.
These measures include pixel density,
circularity,
perimeter,
span ratio and other metrics
for the overall shape of the area
occupied by foreground pixels
in binary images.
If this option is not selected, then
the options to make the hull
and circle graphics
are not available.
None are available for
Multifractal or
Sliding Box Lacunarity
Scans.
The hull and circle and metrics are not available for
gray scale images;
convert them to binary to use these options.
Complementary Metrics Superimposed on Original Image
The image shows the Bounding Box, Convex Hull with Spanning Radii, and Bounding Circle. Note that FracLac draws on the binary image being processed; these were drawn on the original image with a graphic overlay.
bounding circle - Show circle for binary images
Draw on screen or save an image showing the bounding circle. The bounding circle encloses all foreground pixels. The option is available for binary scans except Multifractal and Sliding Box Lacunarity scans, but not grayscale scans. To activate, select a binary scan, then select the option to include METRICS.
Bounding Circles for Simple Geometric Shapes
The bounding circle encloses all foreground pixels from a central radius.
convex hull - Show hull for binary images
The convex hull encloses all foreground pixels in straight line segments. The option is available for binary scans except Multifractal and Sliding Box Lacunarity scans, but not grayscale scans. To activate, select a binary scan, then select the option to include METRICS.
Hull and Circle for Henon Multifractal
These images show the convex hull and bounding circle for a Henon multifractal. FracLac draws the hull and circle if these options are selected.
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