SAGA-GIS Tool Library Documentation (v9.1.2)

Tool Geodesic Morphological Reconstruction

Geodesic morphological reconstruction according to Vincent (1993). Here we use the algorithm on p. 194: Computing of Regional Maxima and Breadth-first Scanning.

A marker is derived from the input grid by subtracting a constant shift value. Optionally, the shift value can be set to zero at the border of the grid ("Preserve 1px border Yes/No" parameter). The final result is a grid showing the difference between the input image and the morphological reconstruction of the marker under the input image. If the Option "Create a binary mask" is selected, the difference grid is thresholded with provided threshold value to create a binary image of maxima regions.


References


Parameters

 NameTypeIdentifierDescriptionConstraints
InputInput GridGrid, inputINPUT_GRIDInput for the morphological reconstruction-
OutputMorphological ReconstructionGrid, outputDIFFERENCE_GRIDReconstruction, difference to input grid.-
Objects (*)Grid, output, optionalOBJECT_GRIDBinary object mask-
OptionsGrid SystemGrid systemPARAMETERS_GRID_SYSTEM--
Shift ValueFloating pointSHIFT_VALUE-Default: 5.000000
Preserve 1px borderBooleanBORDER_YES_NO-Default: 1
ThresholdFloating pointTHRESHOLDThreshold for object identification.Minimum: 0.000000
Default: 1.000000
(*) optional

Command-line

Usage: saga_cmd grid_filter 12 [-INPUT_GRID <str>] [-DIFFERENCE_GRID <str>] [-OBJECT_GRID <str>] [-SHIFT_VALUE <double>] [-BORDER_YES_NO <str>] [-THRESHOLD <double>]
  -INPUT_GRID:<str>     	Input Grid
	Grid, input
  -DIFFERENCE_GRID:<str>	Morphological Reconstruction
	Grid, output
  -OBJECT_GRID:<str>    	Objects
	Grid, output, optional
  -SHIFT_VALUE:<double> 	Shift Value
	Floating point
	Default: 5.000000
  -BORDER_YES_NO:<str>  	Preserve 1px border
	Boolean
	Default: 1
  -THRESHOLD:<double>   	Threshold
	Floating point
	Minimum: 0.000000
	Default: 1.000000