Tool Vegetation Index (Slope Based)
Slope based vegetation indices.
- Difference Vegetation Index
    DVI = NIR - R 
- Normalized Difference Vegetation Index (Rouse et al. 1974)
    NDVI = (NIR - R) / (NIR + R) 
- Ratio Vegetation Index (Richardson and Wiegand, 1977)
    RVI = R / NIR 
- Normalized Ratio Vegetation Index (Baret and Guyot, 1991)
    NRVI = (RVI - 1) / (RVI + 1) 
- Transformed Vegetation Index (Deering et al., 1975)
    TVI = [(NIR - R) / (NIR + R) + 0.5]^0.5 
- Corrected Transformed Ratio Vegetation Index (Perry and Lautenschlager, 1984)
    CTVI = [(NDVI + 0.5) / abs(NDVI + 0.5)] * [abs(NDVI + 0.5)]^0.5 
- Thiam's Transformed Vegetation Index (Thiam, 1997)
    RVI = [abs(NDVI) + 0.5]^0.5 
- Soil Adjusted Vegetation Index (Huete, 1988)
    SAVI = [(NIR - R) / (NIR + R + L)] * (1 + L) 
(NIR = near infrared, R = red, S = soil adjustment factor)
References
- Huete, A.R. (1988): A soil-adjusted vegetation index (SAVI). Remote Sensing of Environment, vol. 25, issue 3, pp. 259-309. https://doi.org/10.1016/0034-4257(88)90106-X.
 - McCloy, K.R. (2006): Resource Management Information Systems: Remote Sensing, GIS and Modelling. 2nd Edition, CRC Taylor & Francis, 575pp.
 - Mroz, M., Sobieraj, A. (2004): Comparison of Several Vegetation Indices Calculated on the Basis of a Seasonal Spot XS Time Series, and their Suitability for Land Cover and Agricultural Crop Identification. Technical Sciences, No. 7, 39-66. http://www.uwm.edu.pl/wnt/technicalsc/ts7_2004/4_7_2004.pdf.
 - Silleos, N.G., Alexandridis, T.K., Gitas, I.Z., Perakis, K. (2006): Vegetation Indices: Advances Made in Biomass Estimation and Vegetation Monitoring in the Last 30 Years. Geocarto International, 21:4, 21-28. http://dx.doi.org/10.1080/10106040608542399.
 
- Author: V.Olaya (c) 2004, O.Conrad (c) 2011
 
- Menu: Imagery|Vegetation Indices
 
Parameters
|   | Name | Type | Identifier | Description | Constraints | 
| Input | Red Reflectance | grid, input | RED | - | - | 
 | Near Infrared Reflectance | grid, input | NIR | - | - | 
| Output | Difference Vegetation Index (*) | grid, output, optional | DVI | - | - | 
 | Normalized Difference Vegetation Index (*) | grid, output, optional | NDVI | - | - | 
 | Ratio Vegetation Index (*) | grid, output, optional | RVI | - | - | 
 | Normalized Ratio Vegetation Index (*) | grid, output, optional | NRVI | - | - | 
 | Transformed Vegetation Index (*) | grid, output, optional | TVI | - | - | 
 | Corrected Transformed Vegetation Index (*) | grid, output, optional | CTVI | - | - | 
 | Thiam's Transformed Vegetation Index (*) | grid, output, optional | TTVI | - | - | 
 | Soil Adjusted Vegetation Index (*) | grid, output, optional | SAVI | - | - | 
| Options | Grid System | grid system | PARAMETERS_GRID_SYSTEM | - | - | 
 | Soil Adjustment Factor | floating point number | SOIL | For SAVI, suggested values (after Silleos et al. 2006): 1.0 = very low, 0.5 = intermediate, 0.25 = high densitity vegetation. | Minimum: 0.000000 Maximum: 1.000000 Default: 0.500000 | 
| (*) optional | 
Command-line
Usage: saga_cmd imagery_tools 1 [-RED <str>] [-NIR <str>] [-DVI <str>] [-NDVI <str>] [-RVI <str>] [-NRVI <str>] [-TVI <str>] [-CTVI <str>] [-TTVI <str>] [-SAVI <str>] [-SOIL <double>]
  -RED:<str>    	Red Reflectance
	grid, input
  -NIR:<str>    	Near Infrared Reflectance
	grid, input
  -DVI:<str>    	Difference Vegetation Index
	grid, output, optional
  -NDVI:<str>   	Normalized Difference Vegetation Index
	grid, output, optional
  -RVI:<str>    	Ratio Vegetation Index
	grid, output, optional
  -NRVI:<str>   	Normalized Ratio Vegetation Index
	grid, output, optional
  -TVI:<str>    	Transformed Vegetation Index
	grid, output, optional
  -CTVI:<str>   	Corrected Transformed Vegetation Index
	grid, output, optional
  -TTVI:<str>   	Thiam's Transformed Vegetation Index
	grid, output, optional
  -SAVI:<str>   	Soil Adjusted Vegetation Index
	grid, output, optional
  -SOIL:<double>	Soil Adjustment Factor
	floating point number
	Minimum: 0.000000
	Maximum: 1.000000
	Default: 0.500000