This page explains features returned when the convex hull and minimum bounding circle are calculated in FracLac (during box counting, sub scans, and LCFD scans). The illustration below shows the convex hull and radii for a binarized image of a neuron. 
Click on a column heading in the screen shots of the Hull and Circle Results file below or read through the list below the screen shots to find out about each column in the file.See the Glossary and Morphometrics page for background.
Circularity
Circularity of the convex hull = 4π×area⁄perimeter2; for a circle it is 1
Perimeter
The perimeter in pixels of the convex hull.
Area
The area, in pixels2, of the convex hull.
Maximum Span Across Hull
The maximum distance in pixels between points across the convex hull.
Hull's Centre of Mass
X,Y coordinates of the convex hull's centre of mass calculated in ImageJ.
Span Ratio (major/minor axis)
The ratio of the major over the minor axes of the convex hull.
Density
Foreground Pixels/Hull Area; the unit is pixels/pixels2 or pixels-1
Total Pixels
The total pixels (foreground and background) in the part of the image that was analyzed.
Total Foreground Pixels
The total pixels deemed foreground in the part of the image that was analyzed. See glossary also.
File/Slice/Roi
Tells which part of the image was analyzed; see explanation of the file name in the tutorial for details.
Mean Radius
The mean length in pixels from the centre of mass of the convex hull to an exterior point.
CV for all Radii
The relative variation in the length of radii from the centre of mass of the convex hull to an exterior point.
Max/Min Radii
The ratio of the largest to the smallest radius from the centre of mass of the convex hull to an exterior point.
Maximum Radius from Hull's Centre of Mass
The maximum radius from the centre of mass for the convex hull to an exterior point.
Height
The height in pixels of the bounding box (the rectangle enclosing the foreground pixels of the image as oriented on the computer screen).
Width
The width in pixels of the bounding box (the rectangle enclosing the foreground pixels of the image as oriented on the computer screen).
Method
The method used to find the bounding circle, calculated using the maximum span across or else the three points defining the smallest circle around the convex hull.
Mean Radius from Circle's Centre
The mean radius from the circle's centre to the points of the convex hull.
CV for all Radii from Circle's Centre
The cv for all radii from the circle's centre to the points of the convex hull.
Max/Min Radii from Circle's Centre
The ratio of the maximum over the minimum radii from the circle's centre to a point on the convex hull.
Maximum Radius from Circle's Centre
The maximum radius (in pixels) from the circle's centre to a point on the convex hull.
Diameter of the Bounding Circle
The diameter in pixels of the smallest circle enclosing the convex hull enclosing the foreground pixels of an image. This is a measure of cell size for biological cells. Compare the area of this circle with the area of the convex hull.
Circle's Centre
The centre x,y coordinates of the bounding circle.