Awesome Spectral Indices

Awesome Spectral Indices

A ready-to-use curated list of Spectral Indices for Remote Sensing applications.

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Spectral Indices

Spectral Indices are widely used in the Remote Sensing community. This repository keeps track of classical as well as novel spectral indices for different Remote Sensing applications. All spectral indices in the repository are curated and can be used in different environments and programming languages. You can check the curated list of spectral indices here, and if you want to use it in your environment, it is available in CSV and JSON.

Attributes

All spectral indices follow a standard. Each item of the list has the following attributes:

  • short_name: Short name of the index (e.g. "NDWI").

  • long_name: Long name of the index (e.g. "Normalized Difference Water Index").

  • formula: Expression/formula of the index (e.g. "(G - N)/(G + N)").

  • bands: List of required bands/parameters for the index computation (e.g. ["N","G"]).

  • reference: Link to the index reference/paper/doi (e.g. "https://doi.org/10.1080/01431169608948714").

  • type: Type/application of the index (e.g. "water").

  • date_of_addition: Date of addition to the list (e.g. "2021-04-07").

  • contributor: GitHub user link of the contributor (e.g. "https://github.com/davemlz").

Expressions

The formula of the index is presented as a string/expression (e.g. "(N - R)/(N + R)") that can be easily evaluated. The parameters used in the expression for each index follow this standard:

Standard variables for spectral indices expressions and satellite equivalents.

Description

Standard

Sentinel-1

Sentinel-2

Landsat 8

Landsat 457

MODIS

Aerosols

A

B1

B1

Blue

B

B2

B2

B1

B3

Green

G

B3

B3

B2

B4

Red

R

B4

B4

B3

B1

Red Edge 1

RE1

B5

Red Edge 2

RE2

B6

Red Edge 3

RE3

B7

NIR

N

B8

B5

B4

B2

NIR 2

N2

B8A

SWIR 1

S1

B11

B6

B5

B6

SWIR 2

S2

B12

B7

B7

B7

Thermal 1

T1

B10

B6

Thermal 2

T2

B11

Backscattering Coefficient HV

HV

HV

Backscattering Coefficient VH

VH

VH

Backscattering Coefficient HH

HH

HH

Backscattering Coefficient VV

VV

VV

Additional index parameters also follow a standard:

  • g: Gain factor (e.g. Used for EVI).

  • L: Canopy background adjustment (e.g. Used for SAVI and EVI).

  • C1: Coefficient 1 for the aerosol resistance term (e.g. Used for EVI).

  • C2: Coefficient 2 for the aerosol resistance term (e.g. Used for EVI).

  • cexp: Exponent used for OCVI.

  • nexp: Exponent used for GDVI.

  • alpha: Weighting coefficient used for WDRVI, BWDRVI and NDPI.

  • beta: Calibration parameter used for NDSIns.

  • gamma: Weighting coefficient used for ARVI.

  • omega: Weighting coefficient used for MBWI.

  • sla: Soil line slope.

  • slb: Soil line intercept.

  • PAR: Photosynthetically Active Radiation.

  • k: Slope parameter by soil used for NIRvH2.

  • lambdaN: NIR wavelength used for NIRvH2 and NDGI.

  • lambdaR: Red wavelength used for NIRvH2 and NDGI.

  • lambdaG: Green wavelength used for NDGI.

The kernel indices are constructed using a special type of parameters:

  • kAB: Kernel of bands/parameters A and B (e.g. kNR means k(N,R), where k is the kernel function).

  • p: Kernel degree (used for the polynomial kernel).

  • c: Free parameter that trades off the influence of higher-order versus lower-order terms (used for the polynomial kernel).

Call for Indices!

Researchers that have published (or aim to publish) their novel spectral indices are encouraged to add them to this repository! The list of spectral indices is used as a source for different resources that allow spectral indices computation in different environments (such as Python and Google Earth Engine). To add an index, please follow the Contribution Guidelines.

In the same line, if you know an spectral index that is not included in this repository, you are encouraged to add it! Please follow the Contribution Guidelines in order to add it.

And one more thing: If you see an error in one or several indices, please report it or update the index (indices) by following the Contribution Guidelines!

There is no deadline. The repository is continuously updated!

Used by

JavaScript

  • spectral: Awesome Spectral Indices for the Google Earth Engine JavaScript API (Code Editor).

Python

  • eemont: A python package that extends Google Earth Engine.

  • eeExtra: A Python package that unifies the Google Earth Engine ecosystem.

  • spyndex: Awesome Spectral Indices in Python.

R

  • rgeeExtra: High-level functions to process spatial and simple Earth Engine objects.

List

Check the full list of spectral indices here.

Download Raw Files

You can download or clone the repository:

git clone https://github.com/davemlz/awesome-ee-spectral-indices.git

Or you can download the single files here (right-click > Save link as…):

Credits