Author: Gary Chinga (gary.chinga@pfi.no) History: 2002/06/03: First version
2002/09/06: Added option to display single particle shape descriptorsRequires: ImageJ 1.28 or later Source: Shape_Descriptors.java Installation: Download Shape_Descriptors.class to the plugins folder and restart ImageJ. Description: This plugin calculates shape descriptors. The mean and standard deviation of shape values are given for every image in a stack. The definitions are given according to Russ, 1999 (The image processing Handbook). The following descriptors are given: Form factor: 4pi*area/sqr(perimeter)The Analyze/Set Measurements... "Limit to Threshold" option must be checked (only thresholded pixels are included in measurement calculations). Use Image/Adjust/Threshold to set the threshold limits. Edge particles must also be excluded during measurement.
Roundness: 4*area/pi*sqr(major axis)
Compactness: sqrt((4/pi)*area)/major axis
Aspect Ratio: major axis/minor axis