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PathTurnAngleLocalMaxima

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Module: FoundationPro

Finds the local maxima of the profile of turn angles of a path.

Applications

Detection of feature points related to object corners.
Name Type Range Description
Input value
 inPath Path Input path
Input value
 inAllowedTurnDirection TurnAngleDirection Allows to detect only left-turns, only right-turns or both
Input value
 inResultPrecision TurnAnglePrecision Switches between pixel-precise or subpixel-precise detection of the found maxima
Input value
 inMinTurnAngle Real 0.0 - 180.0 Minimal value of a relevant angle
Input value
 inMinDistance Real 0.0 - Minimal distance on the path between two local maxima assuming each path segment has unit length
Input value
 inSmoothingStdDev Real 0.0 - Standard deviation of the gaussian smoothing applied to the input path
Output value
 outTurnAngleMaximaIndices RealArray Indices of found local maxima
Output value
 outTurnAngleMaximaPoints Point2DArray Found local maxima of turn angle profile of the smoothed input path
Output value
 outTurnAngleMaximaAngles RealArray Turn angles of found local maxima
Diagnostic input
 diagSmoothedPath Path Input path smoothed with gaussian kernel
Diagnostic input
 diagTurnAngleProfile Profile Profile of turn angles at characteristic points of the smoothed input path

Description

The operation computes the profile of turn angles of a path and finds the local maxima of the profile having value at least inMinTurnAngle. The inAllowedTurnDirection parameter restricts kind of turns taken into consideration (left-turns only, right-turns only or both), while inResultPrecision determines the precision of the resulting maxima points. Found maxima have to be at least inMinDistance from each other (the distance is measured along the input path assuming each path segment has unit length).

Examples

PathTurnAngleLocalMaxima run on the sample path with inAllowedTurnDirection = Right

Complexity Level

This filter is available on Advanced Complexity Level.

See Also