Tool Terrain Surface Convexity

Terrain surface convexity as proposed by Iwahashi & Pike (2007) for subsequent terrain classification.

References

Iwahashi, J. & Pike, R.J. (2007): Automated classifications of topography from DEMs by an unsupervised nested-means algorithm and a three-part geometric signature.

Author: O.Conrad (c) 2012
Menu: Terrain Analysis|Morphometry

Parameters

	Name	Type	Identifier	Description	Constraints
Input	Elevation	Grid (input)	`DEM`	-	-
Output	Convexity	Grid (output)	`CONVEXITY`	-	-
Options	Grid system	Grid system	`PARAMETERS_GRID_SYSTEM`	-	-
	Laplacian Filter Kernel	Choice	`KERNEL`	-	Available Choices: [0] conventional four-neighbourhood [1] conventional eight-neihbourhood [2] eight-neihbourhood (distance based weighting) Default: 0
	Type	Choice	`TYPE`	-	Available Choices: [0] convexity [1] concavity Default: 0
	Flat Area Threshold	Floating point	`EPSILON`	-	Minimum: 0.000000 Default: 0.000000
	Scale (Cells)	Integer	`SCALE`	-	Minimum: 1 Default: 10
	Method	Choice	`METHOD`	-	Available Choices: [0] counting cells [1] resampling Default: 1
	Weighting Function	Choice	`DW_WEIGHTING`	-	Available Choices: [0] no distance weighting [1] inverse distance to a power [2] exponential [3] gaussian weighting Default: 3
	Inverse Distance Weighting Power	Floating point	`DW_IDW_POWER`	-	Minimum: 0.000000 Default: 1.000000
	Inverse Distance Offset	Boolean	`DW_IDW_OFFSET`	Calculates weights for distance plus one, avoiding division by zero for zero distances	Default: 1
	Gaussian and Exponential Weighting Bandwidth	Floating point	`DW_BANDWIDTH`	-	Minimum: 0.000000 Default: 0.700000

Command-line

Usage: saga_cmd ta_morphometry 21 [-DEM <str>] [-CONVEXITY <str>] [-KERNEL <str>] [-TYPE <str>] [-EPSILON <double>] [-SCALE <num>] [-METHOD <str>] [-DW_WEIGHTING <str>] [-DW_IDW_POWER <double>] [-DW_IDW_OFFSET <str>] [-DW_BANDWIDTH <double>]
  -DEM:<str>            	Elevation
	Grid (input)
  -CONVEXITY:<str>      	Convexity
	Grid (output)
  -KERNEL:<str>         	Laplacian Filter Kernel
	Choice
	Available Choices:
	[0] conventional four-neighbourhood
	[1] conventional eight-neihbourhood
	[2] eight-neihbourhood (distance based weighting)
	Default: 0
  -TYPE:<str>           	Type
	Choice
	Available Choices:
	[0] convexity
	[1] concavity
	Default: 0
  -EPSILON:<double>     	Flat Area Threshold
	Floating point
	Minimum: 0.000000
	Default: 0.000000
  -SCALE:<num>          	Scale (Cells)
	Integer
	Minimum: 1
	Default: 10
  -METHOD:<str>         	Method
	Choice
	Available Choices:
	[0] counting cells
	[1] resampling
	Default: 1
  -DW_WEIGHTING:<str>   	Weighting Function
	Choice
	Available Choices:
	[0] no distance weighting
	[1] inverse distance to a power
	[2] exponential
	[3] gaussian weighting
	Default: 3
  -DW_IDW_POWER:<double>	Inverse Distance Weighting Power
	Floating point
	Minimum: 0.000000
	Default: 1.000000
  -DW_IDW_OFFSET:<str>  	Inverse Distance Offset
	Boolean
	Default: 1
  -DW_BANDWIDTH:<double>	Gaussian and Exponential Weighting Bandwidth
	Floating point
	Minimum: 0.000000
	Default: 0.700000