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NAME
i.wi - Calculates different types of water indices.
KEYWORDS
imagery,
water,
index,
biophysical
SYNOPSIS
i.wi
i.wi --help
i.wi winame=type [blue=name] [green=name] [red=name] [nir=name] [band5=name] [band7=name] output=name [--overwrite] [--help] [--verbose] [--quiet] [--ui]
Flags:
- --overwrite
- Allow output files to overwrite existing files
- --help
- Print usage summary
- --verbose
- Verbose module output
- --quiet
- Quiet module output
- --ui
- Force launching GUI dialog
Parameters:
- winame=type [required]
- Type of water index
- Options: awei_ns, awei_s, lswi, ndwi_mf, ndwi_x, tcw, wi
- Default: lswi
- awei_ns: Automated Water Extraction Index - No Shadow
- awei_s: Automated Water Extraction Index - Shadow
- lswi: Land Soil Water Index
- ndwi_mf: Normalized Difference Water Index - Mc Feeters
- ndwi_x: Normalized Difference Water Index - Xu
- tcw: Tasseled Cap Water
- wi: Water Index
- blue=name
- Name of input blue channel surface reflectance map
- Range: [0.0;1.0]
- green=name
- Name of input green channel surface reflectance map
- Range: [0.0;1.0]
- red=name
- Name of input red channel surface reflectance map
- Range: [0.0;1.0]
- nir=name
- Name of input nir channel surface reflectance map
- Range: [0.0;1.0]
- band5=name
- Name of input 5th channel surface reflectance map
- Range: [0.0;1.0]
- band7=name
- Name of input 7th channel surface reflectance map
- Range: [0.0;1.0]
- output=name [required]
- Name of the output wi layer
i.wi calculates water indices based on biophysical parameters.
- AWEI: Automated Water Extraction Index (2 versions: no shadow or shadow
- LSWI: Land Surface Water Index
- NDWI: Normalized Difference Water Index (2 versions: McFeeters or Xu)
- TCW: Tasseled Cap Water
- WI: Water Index
Requirements (as of Landsat 5TM bands)
- awei_noshadow needs greenchan, nirchan, chan5chan
- awei_shadow needs bluechan, greenchan, nirchan, chan5chan, chan7chan
- ls_wi needs nirchan, chan7chan
- ndwi_mcfeeters needs greenchan, nirchan
- ndwi_xu needs greenchan, chan5chan
- tcw needs bluechan, greenchan, redchan, nirchan, chan5chan, chan7chan
- wi needs greenchan, redchan, nirchan, chan5chan, chan7chan
Find other water indices and add them.
- AWEI: Automated Water Extraction Index
Feyisa, G.L., Meilby, H., Fensholt, R., Proud, S.R. (2014).
Automated Water Extraction Index: A new technique for surface water mapping using Landsat imagery.
Remote Sensing of Environment, 140, 23-35. http://dx.doi.org/10.1016/j.rse.2013.08.029.
- LSWI: Land Surface Water Index
a kind of Normalized Difference Water Index
Xiao X., Boles S., Frolking S., Salas W., Moore B., Li C., et al. (2002)
Landscape-scale characterization of cropland in China using vegetation and Landsat TM images.
International Journal of Remote Sensing, 23:3579-3594.
- NDWI McFeeters
McFeeters, S.K. (1996).
The use of the Normalized Difference Water Index (NDWI) in the delineation of open water features.
International Journal of Remote Sensing, 17, 1425-1432. http://dx.doi.org/10.1080/01431169608948714.
- NDWI Xu
Xu, H. (2006).
Modification of normalised difference water index (NDWI) to enhance open water features in remotely sensed imagery.
International Journal of Remote Sensing, 27, 3025-3033. http://dx.doi.org/10.1080/01431160600589179.
- TCW
Crist, E.P. (1985).
A TM tasseled cap equivalent transformation for reflectance factor data.
Remote Sensing of Environment, 17, 301-306.
- WI
Fisher, A., Flood, N., Danaher, T. (2016).
Comparing Landsat water index methods for automated water classification in eastern Australia.
Remote Sensing of Environment, 175, 167-182. ISSN 0034-4257, http://dx.doi.org/10.1016/j.rse.2015.12.055.
i.vi
Yann Chemin
SOURCE CODE
Available at:
i.wi source code
(history)
Latest change: Monday Jun 28 07:54:09 2021 in commit: 1cfc0af029a35a5d6c7dae5ca7204d0eb85dbc55
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