Measure shape parameters of the object
#include "dip_measurement.h"
dip_int dip_FeatureShapeID ( void )
dip_FloatArray
dip_FeatureShapeID returns the ID value of this measurement function, that is registered by Initialise.
This function is a composite measurement function, that uses FeatureSize, FeaturePerimeter, and FeatureFeret to measure the following shape characteristics of 2D objects:
| Squarity | area / ( s * sp ) |
| Circularity | area / ( Pi/4 * sp^2 ) |
| Triangularity | area / ( 1/2 * s * sp ) |
| Elliticity | area / ( Pi/4 * s * sp ) |
| Elongation | p / l |
with area the size, s the shortest Feret diameter, l the longest Feret diameter, sp the Feret diameter perpendicular to s, and p the perimeter of the object. The values in the output array are given in this order.
When the measured object is either a perfect square, circle, triangle or ellipse, the values obtained by FeatureShape will be 1.0.
This function assumes isotropic sampling, even if the physical dimensions given through the Measure function say otherwise.
This function uses chain codes. It expects each measured object to be compact, that is, to have only one chain code. Additional chain codes are ignored, meaning that non-compact objects are not measured properly. Take care in providing the correct connectivity value: if you object is compact only with 2-connectivity, this measure will fail if you call Measure with a value of 1 for the connectivity.
FeatureAnisotropy2D, FeatureBendingEnergy, FeatureCenter, FeatureChainCodeBendingEnergy, FeatureConvexArea, FeatureConvexPerimeter, FeatureConvexity, FeatureDimension, FeatureExcessKurtosis, FeatureFeret, FeatureGinertia, FeatureGmu, FeatureGravity, FeatureInertia, FeatureLongestChaincodeRun, FeatureMass, FeatureMaxVal, FeatureMaximum, FeatureMean, FeatureMinVal, FeatureMinimum, FeatureMu, FeatureOrientation2D, FeatureP2A, FeaturePerimeter, FeatureRadius, FeatureShape, FeatureSize, FeatureSkewness, FeatureStdDev, FeatureSum, FeatureSurfaceArea