Definitions of the 12 imageJ-based indices used in this study.
Category | Index | Description |
---|---|---|
Size | Area | Area of selection in square pixels or in calibrated square units |
Perimeter | The length of the outside boundary of the selection | |
Diameter | Height | Measure the height of a digitized object with ROI |
Width | Measure the width of a digitized object with ROI | |
Major | Major axis (transverse diameter) | |
Minor | Minor axis (conjugate diameter) | |
Feret | The longest distance between any two points along the selection boundary, also known as maximum caliper. | |
MinFeret | The shortest distance between any two points along the selection boundary, also known as minimum caliper. | |
Shape | Aspect ratio | The aspect ratio of the particle’s fitted ellipse, i.e., [Major Axis]/[Minor Axis] |
Roundness | 4×[Area]/(π×[Major axis]^{2} or the inverse of aspect ratio. | |
Circularity | 4π×[Area]/[Perimeter]^{2} with a value of 1.0 indicating a perfect circle. | |
Solidity |
[Area]/[Convex area] *Convex hull can be thought of as a rubber band wrapped tightly around the points that define the selection, and determined by gift wrap algorithm |