Questions tagged [vegetation-index]

For questions about vegetation indices, which are measures of the relative abundance of vegetation. In the context of remote sensing and GIS, vegetation indices are usually encountered as a raster dataset.

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25 views

Google Earth Engine EVI values too high

I am trying to calculate the EVI (enhanced vegetation index) for a Landsat-8 image. The code works, but it returns very high values (ranging from -0.4 to 3000), when the index is supposed to return a ...
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9 views

Where can I find reflectance / VI data for crops for different dates across their growing season?

I have been trying to find literature values for reflectance of soybean for different dates along the growing season (I am specifically interested in 30, 60 and ~120 days after planting - so the V3/V4 ...
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13 views

Possible range for MSAVI and MTVI indices

What are possible value ranges for MSAVI2 and MTVI indices? The article #1 says it should be in range of -1 to 1, but the answer to the question #2 says '[MSAVI2] is not bound to a theoretical -1 to 1 ...
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17 views

Do Sentinel-2 L1C data downloaded from USGS Earth Explorer consist of reflectance values or digital numbers?

I was wondering if Sentinel-2 L1C data downloaded from USGS Earth Explorer consist of reflectance values. And is it necessary to use reflectance values for time series analysis of Sentinel-2 ...
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7 views

Issues calculating VARI from Sentinel L2A

I have a dataset of Sentinel-2 L2A imagery for which I am calculating the Visual Atmospheric Resistant Index (VARI). The bands that I am using (B2 = blue B3 = green B4 = Red) I am working in ArcMap. ...
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1answer
36 views

Extract pixel values from several bands of an image and export in a single table in Google Earth Engine

I am creating several bands of spectral indexes by reducing the S2 TOA image collection. For each spectral index, I am extracting the pixel values at specific locations (a point shapefile represent ...
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1answer
19 views

Add several Spectral Indexes over an image collection in Google Earth Engine

I want to add several spectral indexes in one go over a Sentinel2 TOA collection. If I do only with NDVI the script works. If I add 2 types of NDWI I get the following "Syntax Error: Unespected ...
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12 views

Vegetation detection of anthropic crops with Google Earth Engine

I am very new using Google Engine and I need to know how to detect only agricultural crops on slopes without them mixing with that natural vegetation on hills. I have tried different indexes (like ...
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35 views

How to average the NDDI index for a map in GEE

In previous codes I was able to generate the NDVI average, but since NDDI is a sub-index I would like to know if anyone would be able to generate this NDDI average in GEE https://code.earthengine....
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13 views

clred- edge index for canopy chlorophyll content

I want to use clred-edge chlorophyll index to extract canopy chlorophyll content (CCC) from Sentinel-2 But based on the various articles I've read, I have two questions Is there a numerical range ...
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1answer
26 views

Function only mapped over the first image of the collection

If anyone could help with this please. I need to map a function over an image collection. The problem is that the function is applied only on the first image of the collection and not on the rest. ...
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24 views

ArcGIS - Band Arithmetic - VARI

I have a RGB raster image for which I need to calculate vegetation indices. I have chosen to use VARI from the "Band Arithmetic" options in the "Add Function" tool in the "Image Analysis" window. ...
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1answer
37 views

Loops for calculating vegetation indices for multiple temporal images and each image have multiple bands

I have 64 TIFF files of different dates, each date has 4 bands (123 and 4 for B, G R and NIR). I am trying to develop a Vegetation index for each date image. This is how the images in my folder are [...
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1answer
75 views

Calculating EVI in ArcMap for Landsat 8 Image gives values ranging from 55155 to -23235 [closed]

How do I calculate EVI in ArcMap for Landsat 8 Image? My values are ranging from 55155 to -23235. I have tried using the formula: 2.5 * [(band 5- band 4)/ (band 5 + 6*band 4-7.5* band 2) + 1] I ...
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1answer
57 views

MCARI vegetation index in ArcGIS raster calculator

I'm trying to write the equation for the MCARI vegetation index in raster calculator using WorldView-2 imagery, but can't get it right. Here is the original formula: MCARI = [(RedEdge – Red) – 0.2 × ...
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1answer
214 views

Which band to use for LSWI?

I have a sentinel 2 L1C data and I am trying to calculate the Land Surface Water Index (LSWI) using the NIR and SWIR bands. As the Sentinel 2 data is having 2 SWIR bands (B11 and B12), I am confused ...
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33 views

GEMI vegetation index calculation in ENVI

I want to calculate gemi index, but I can't write its formula in ENVI, this doesn't work. gemi formula is: (n(1−0.25n)−RED−0.1251−RED) n = ( 2 * ( NIR ^2 - RED ^2) + 1.5 * NIR + 0.5 * RED ) / ( NIR ...
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1answer
232 views

Google Earth Engine: Use multiple bounding boxes to extract mean VI value

I am new to GEE with no prior Javascript knowledge. I am trying to find a way to use multiple bounding boxes (which are in bottom-left point x,y and top-right point x,y) from a csv file in order to ...
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1answer
152 views

How do I add multiple indices as bands to an image?

I want to be able to classify my image using bands for prediction (B2, B3, B4, etc.) but I also want to use indices as "bands" (B2, B3, B4, NDVI, EBBI, MSAVI2, etc.). Unfortunately, I can't seem to ...
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71 views

Understanding why MSAVI II values are outside the theoretical range

I am trying to understand why certain vegetation indices do not fall into the -1, 1 theoretical range. I generated Modified Soil Adjusted Vegetation Index II values in Google Earth Engine using ...
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1answer
142 views

Seeking Function to calculate red-edgeNDVI in Google Earth Engine?

I am trying to calculate the red-edgeNDVI ((NIR – red edge)/(NIR + red edge)) of an Image.Collection in Google Earth Engine. There is a built in function for NDVI but not for red-edge NDVI. The code I ...
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1answer
86 views

Moisture Stress Index - how important is seasonal influence in a deciduous forest?

I want to calculate moisture stress index for a deciduous forest using the formula from the article 'Detecting vegetation leaf water content using reflectance in the optical domain' (Ceccato et al. ...
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1answer
622 views

Soil Adjusted Vegetation Index Values (MSAVI2) are Not Within Expected Range

I am using MSAVI2 (Modified Soil Adjusted Vegetation Index 2) to analyze different land cover classes for a study area in southern Africa. The Land cover classes were taken from a Planet Labs ...
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412 views

Calculating Surface Roughness from Land Cover Data/Land Elevation

I'm trying to create a surface roughness file over the continental United States in NetCDF format. I've surface elevation file of 200 meters resolution and land cover data of 30meters resolution. I'm ...
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222 views

Using output of unsupervised cluster analysis to train supervised classification for vegetation mapping?

I'm using Google Earth Engine to classify mangrove forests from Landsat imagery to calculate extent. Let's say I perform an unsupervised K-means cluster analysis on a Landsat scene to identify general ...
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1answer
99 views

Is the resolution of MYD13A2/MOD13A2 ( MODIS 16 day 1km Global Vegetation Indices) erroneous in Google Earth Engine?

The MODIS vegetation indices collection shows a resolution of 111319.4 metres in Google Earth Engine when, in fact, it should be 1000 metres. Below is my code: var Veg = ee.ImageCollection("MODIS/...
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1answer
360 views

Why vegetation index, NDVI or SAVI is not working in the desert?

Could anyone explain why the vegetation indices are not working in the desert region? I used Landsat 8 image which has been already radiometric/atmospheric corrected. I want to see the fractional ...
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2answers
332 views

Calculating vegetation indexes with GDAL raster calculator?

I want to calculate a few of vegetation indexes [ example: NDPI (red band-green band)/(red band + green band)] in a model with the GDAL raster calculator but I don't know how put the equation here:
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1answer
77 views

How to create a dense pointcloud of trees in ArcGIS?

I'm having a large dataset of forest polygons and would like to scatter individual tree locations over these areas. Here is how I have done this so far: In "Create Random Points" number of points has ...
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0answers
111 views

How to georeference multispectral raster without loss of data

I am trying to align two rasters made of data captured during same flight, but with separate cameras (drone - onboard, and Micasense RedEdge) and two separate gps devices (drone and another one ...
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0answers
102 views

When to rescale reflectance data to calculate vegetation indices

I'm attempting to calculate a number of vegetation indices using hyperspectral AVIRIS data in ENVI. Some of these indices are normalized, such as NDVI, whereas others are not, such as the Transformed ...
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91 views

Using Band Math in R Creates Raster with Different Coordinate System?

I am trying to make a simple NDVI raster from a Landsat 8 image (containing bands 2-7). The Landsat image has a Coordinate System of NAD_1983_UTM_Zone_11N (and datum: D_North_American_1983). When I ...
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1answer
369 views

EVI calculation from UAV multispectral survey

I want to calculate EVI index from UAV multispectral survey. For satellite imagery it is pretty straightforward (after reading multiple posts on GIS.SE) but not sure how to approach this problem, when ...
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1answer
1k views

Convertion of spectral indices formulas from Landsat to Sentinel

There are many spectral indices in literature. However, the formulas mostly refer to landsat imagery, and thus the corresponding spectral bands. Question: How can a formula that was originally ...
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2answers
1k views

ENVI band math incorrect values

I'm attempting to calculate vegetation indices in ENVI 5.2 using level-2 AVIRIS data in band math. The indices I'm working with are Vogelmann Red Edge 2, normalized difference red edge, and red edge ...
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1answer
2k views

Calculate MSAVI (Modified Soil-adjusted Vegetation Index) in Google Earth Engine

How do you write the MSAVI formula in JavaScript function for Google Earth Engine? I am trying to calculate the MSAVI as a function. The aim is to map the result over a Sentinel-2 composite and not a ...
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2answers
135 views

Vegetation Index for dry and sparse vegetated areas?

I found many different index for the estimation of vegetation cover, but many of them struggle in sparse areas with low vegetation cover, as the soil signals are way stronger than the vegetation ...
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179 views

EVI2 values dont' come out -1 to 1? [closed]

I'm very new to remote sensing in general, and aren't sure if I've made an error. I've calculated EVI2 for a Landsat 8 and Sentinel 2 image. Both Top of Atmosphere. I've used Google Earth Engine to ...
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1answer
643 views

Calculating forest canopy density and advanced vegetation index in ArcGIS Raster Calculator?

While performing raster calculator operation in ArcGIS for Advanced Vegetation Index ( in calculating forest canopy density), the results show only 2 values i.e high (1) and low ( 0), instead of a ...
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1answer
136 views

How to classify vegetation in 500x500 m polygons in a very coarse way in QGIS

For a simple species distribution map for the Dutch Wadden island of Terschelling, I want to give each 500x500 m polygon (reference grid = EPSG 28992) a specific color that coarsly corresponds with ...
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102 views

Method in QGIS to classify veg from HiRes geotiffs created in Pix4D?

I have 10 2D geoTIFF orthophotos (~2GB each, ~3km2 each, all 4.2cm/pixel) that I generated from Vis RGB 12MP images in Pix4D for a desert vegetation survey over 30km2 for a development. I need to ...
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1answer
198 views

Calculating area for range of values of spectral indices in QGIS?

How do I retrieve the area of a place which I've already calculate the NDVI index? The thing is that I just need the area of the pixels that have values between 0.5 to 0.8 (It is a Landsat 8 image). ...
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2answers
310 views

Atmospheric effects on extracting soil from BSI index?

I need to extract soil from Bare Soil Index (BSI) using Landsat 8 and Sentinel 2 images in QGIS or IDRISI. I was told to start with basic atmospheric correction of bands by finding in the histogram ...
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1answer
185 views

Using vegetation cover and DEM elevation data together

I'm using Terrain data (DEM) from USGS and I would like to build a map in which I can keep the information on the elevation in 3D and on the vegetation cover. I have obtained the 3D raster for the ...
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1answer
61 views

Checking Vegetation height accuracy in urban areas

I have digitized vegetation as polygons covering the canopy of trees in urban areas. Are there any suggestions to check the accuracy of height. I have been manually validating with visual checks, ...
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2answers
1k views

Finding min and max raster values using polygons in ArcMap?

I have a raster dataset that encompasses an area which has previously been classified into vegetation types. I have the classification polygons and want to lay them on top of a vegetation index image ...
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0answers
543 views

List of indices (e.g., NDVI) that can be calculated with satellite images [closed]

I'm looking for a list of published indices that can be calculated from satellite images and the corresponding formula for each: Some indicies, for example, would be: - NDVI: https://en.wikipedia....
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132 views

QGIS: Extract rows of grape vines from inter-row vegetation using a 3D point cloud

I have some multi spectral imagery (raster data) from a UAV of vineyards in Victoria, as well as corresponding 3D point cloud (also raster) of the vineyard topography, based off ultrasonic sensing, ...
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1answer
1k views

Calculation of average NDVI of area in QGIS?

I wish to calculate the average NDVI value of an area (polygon). Thus the average value of all pixel. How can this be done in QGIS?
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2answers
478 views

Applying MODIS Pixel Reliability and Vegetation Index (VI) Quality mask for MOD13Q1 using ArcGIS Desktop?

I have some sets of MODIS MOD13Q1 data sets during March and December for year 2000 to 2015. I need to extract the NDVI and EVI for those two months from the entire 15 years. How do I apply the ...