Thin Plate Spline (TIN)
- Author: O.Conrad (c) 2006
- Menu: Grid | Gridding | Spline Interpolation
Description
Creates a 'Thin Plate Spline' function for each triangle of a TIN and uses it for subsequent gridding. The TIN is internally created from the scattered data points input. The 'Neighbourhood' option determines the number of points used for the spline generation. 'Immediate neighbourhood' includes the points of the triangle as well as the immediate neighbour points. 'Level 1' adds the neighbours of the immediate neighbourhood and 'level 2' adds the neighbours of 'level 1' neighbours too. A higher neighbourhood degree reduces sharp breaks but also increases the computation time. 
References
- Donato G., Belongie S. (2002): Approximation Methods for Thin Plate Spline Mappings and Principal Warps. In: Heyden, A., Sparr, G., Nielsen, M., Johansen, P. [Eds.]: Computer Vision - ECCV 2002: 7th European Conference on Computer Vision, Copenhagen, Denmark, May 28-31, 2002, Proceedings, Part III, Lecture Notes in Computer Science. Springer-Verlag Heidelberg; pp.21-31.
- Elonen, J. (2005): Thin Plate Spline editor - an example program in C++.  http://elonen.iki.fi/code/tpsdemo/index.html.
Parameters
|  | Name | Type | Identifier | Description | Constraints | 
|---|
| Input | Points | shapes, input | SHAPES | - | - | 
| Target System | grid, input, optional | TARGET_TEMPLATE | use this grid's system for output grids | - | 
| Output | Target Grid | grid, output | TARGET_OUT_GRID | - | - | 
| Options | Attribute | table field | FIELD | - | - | 
| Target Grid System | choice | TARGET_DEFINITION | - | Available Choices:
[0] user defined
[1] grid or grid system
Default: 0 | 
| Cellsize | floating point number | TARGET_USER_SIZE | - | Minimum: 0.000000
Default: 1.000000 | 
| West | floating point number | TARGET_USER_XMIN | - | Default: 0.000000 | 
| East | floating point number | TARGET_USER_XMAX | - | Default: 100.000000 | 
| South | floating point number | TARGET_USER_YMIN | - | Default: 0.000000 | 
| North | floating point number | TARGET_USER_YMAX | - | Default: 100.000000 | 
| Columns | integer number | TARGET_USER_COLS | Number of cells in East-West direction. | Minimum: 1
Default: 101 | 
| Rows | integer number | TARGET_USER_ROWS | Number of cells in North-South direction. | Minimum: 1
Default: 101 | 
| Fit | choice | TARGET_USER_FITS | - | Available Choices:
[0] nodes
[1] cells
Default: 0 | 
| Grid System | grid system | TARGET_SYSTEM | - | - | 
| Regularisation | floating point number | REGULARISATION | - | Minimum: 0.000000
Default: 0.000100 | 
| Neighbourhood | choice | LEVEL | - | Available Choices:
[0] immediate
[1] level 1
[2] level 2
Default: 1 | 
| Add Frame | boolean | FRAME | - | Default: 1 | 
Command Line
Usage: saga_cmd grid_spline 2 [-SHAPES ] [-FIELD ] [-TARGET_DEFINITION ] [-TARGET_USER_SIZE ] [-TARGET_USER_XMIN ] [-TARGET_USER_XMAX ] [-TARGET_USER_YMIN ] [-TARGET_USER_YMAX ] [-TARGET_USER_COLS ] [-TARGET_USER_ROWS ] [-TARGET_USER_FITS ] [-TARGET_TEMPLATE ] [-TARGET_OUT_GRID ] [-REGULARISATION ] [-LEVEL ] [-FRAME ]
  -SHAPES:             	Points
	shapes, input
  -FIELD:              	Attribute
	table field
  -TARGET_DEFINITION:  	Target Grid System
	choice
	Available Choices:
	[0] user defined
	[1] grid or grid system
	Default: 0
  -TARGET_USER_SIZE:	Cellsize
	floating point number
	Minimum: 0.000000
	Default: 1.000000
  -TARGET_USER_XMIN:	West
	floating point number
	Default: 0.000000
  -TARGET_USER_XMAX:	East
	floating point number
	Default: 100.000000
  -TARGET_USER_YMIN:	South
	floating point number
	Default: 0.000000
  -TARGET_USER_YMAX:	North
	floating point number
	Default: 100.000000
  -TARGET_USER_COLS:   	Columns
	integer number
	Minimum: 1
	Default: 101
  -TARGET_USER_ROWS:   	Rows
	integer number
	Minimum: 1
	Default: 101
  -TARGET_USER_FITS:   	Fit
	choice
	Available Choices:
	[0] nodes
	[1] cells
	Default: 0
  -TARGET_TEMPLATE:    	Target System
	grid, input, optional
  -TARGET_OUT_GRID:    	Target Grid
	grid, output
  -REGULARISATION:  	Regularisation
	floating point number
	Minimum: 0.000000
	Default: 0.000100
  -LEVEL:              	Neighbourhood
	choice
	Available Choices:
	[0] immediate
	[1] level 1
	[2] level 2
	Default: 1
  -FRAME:              	Add Frame
	boolean
	Default: 1