SAVI
The soil-adjusted vegetation index from red and near-infrared reflectance, with the soil adjustment factor L, for scenes where bare ground shows through.
Experimental: not yet fully verified. How results are checked
SAVI is 0.5388.
Provenance
- Computed by
- raster.index.savi 1.0.0, core 0.1.0
- Model
- SAVI = (1 + L)(NIR - Red) / (NIR + Red + L), L = 0.5 unless given (Huete 1988)
- Accuracy
- Exact arithmetic on the reflectance given.
- Notes
- 1 shown with the answer
- Cites
- Huete, A. R., Remote Sensing of Environment, A soil-adjusted vegetation index (SAVI)
Something look off?
How we got thisFormula, worked example, sources, and proof
Model: SAVI = (1 + L)(NIR - Red) / (NIR + Red + L), L = 0.5 unless given (Huete 1988)
Accuracy: Exact arithmetic on the reflectance given.
When to use this: Use this where the ground shows between plants — rangeland, early growth, arid and semi-arid scenes — because soil brightness pushes NDVI around in exactly those conditions. The L factor sets how much of that soil effect is taken out: 1 for very sparse cover, 0.5 in between, 0 for closed canopy, where SAVI becomes NDVI scaled.
Limitations: L has to be chosen, and the right value depends on the cover you are trying to measure, which is often what you are trying to find out; the 0.5 default is a compromise from the original paper. It does not remove the soil signal, it reduces it, and it shares NDVI's saturation over dense canopy.
Worked example: SAVI over sparse cover. Source: Huete 1988 formula with L = 0.5: NIR 0.45 and red 0.08 give 0.5388. It is golden test vector v001, and every build checks the tool still gives its answer within its tolerance.
You enter
- Near-infrared reflectance
- 0.45
- Red reflectance
- 0.08
You get
- SAVI
- 0.5388
Review: Not yet independently reviewed by a GIS professional.
Last verified: 2026-09-22, when a maintainer last confirmed this tool's sources at the issuer. See the sources ledger.
Status: version 1.0.0, core 0.1.0. See this tool in the verification report.
Checked against: 30 golden test vectors (download the test vectors, each with its source and tolerance). See how results are checked and every source.
Sources
- A soil-adjusted vegetation index (SAVI), Huete, A. R., Remote Sensing of Environment, Volume 25, issue 3, pages 295-309. SAVI = (1 + L)(NIR - Red) / (NIR + Red + L), with L = 0.5 for intermediate cover.
Terms
- SAVI: soil-adjusted vegetation index
- NDVI with a soil adjustment factor L, for scenes where bare ground between plants would otherwise dominate the signal. Source: A soil-adjusted vegetation index (SAVI)
Experimental means this tool has not yet met the stable bar: at least 20 golden vectors, differential tests, and an independent worked example.