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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18
votes
3answers
2k views

Alternative vegetation indices

I have been using NDVIs with limited success to identify trees in the central Great Plains region of the USA. The problem I have been encountering is that reflectance from farm fields/pastures have ...
6
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1answer
388 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 ...
4
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1answer
369 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 ...
3
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1answer
3k views

Tutorial Vegetation Condition Index

Anybody here can help me regarding calculating Vegetation Condition Index (Kogan,2004) for Landsat?. Specially facing problem in NDVI_max and NDVI_min; which should be maximum and minimum value?
3
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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 ...
3
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2answers
321 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 ...
3
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3answers
2k views

How to analyze Vegetation Index using Sentinel-1 SAR Imagery?

I am using the ESA open scientific data hub for Sentinel 1 SAR imagery (Interferometric Wide swath SLC VV polarization) and would like to know how to perform vegetation health analysis from this data? ...
3
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2answers
86 views

Batch processing Vegetation Index with QGIS Raster Calculator

I'm applying the Green Leaf Index (GLI) to a multi-temporal set of RGB raster images to generate false colour overlays of the sections of the hay field. I can create GLI layers using the raster ...
3
votes
1answer
689 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 ...
3
votes
1answer
217 views

How to represent seasonal variability in a single global NDVI map?

I have twelve monthly MODIS datasets for a 1 year period (http://neo.sci.gsfc.nasa.gov/view.php?datasetId=MOD13A2_M_NDVI&year=2015) and wish to combine all the data into a single map highlighting ...
3
votes
1answer
606 views

Creating NRG Multiband TIF from single bands using QGIS?

I'm attempting to take 3 single bands (NIR, Red, and Green) and turn them into a single multiband tif image. Someone working on the images was able to take this image which I merged... And then ...
3
votes
2answers
137 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 ...
2
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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 ...
2
votes
1answer
139 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 ...
2
votes
1answer
38 views

Performing complicated calculation on bands in Google Earth Engine

I'm trying to perform ANIR index calculation on my image collection. I'm having trouble writing the code in the right way. ANIR index formula is : cos^-1[((a^2)+(b^2)+(c^2))/(2*a*b)] (a2, b2 and c1, ...
2
votes
1answer
183 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 ...
2
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0answers
115 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 ...
2
votes
2answers
2k 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 ...
2
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0answers
189 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 ...
1
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1answer
155 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 ...
1
vote
1answer
20 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 ...
1
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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 ...
1
vote
1answer
90 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 ...
1
vote
1answer
66 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 × ...
1
vote
1answer
255 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 ...
1
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1answer
201 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). ...
1
vote
1answer
187 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 ...
1
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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, ...
1
vote
1answer
240 views

Discrepancies in remotely sensed indices using Sentinel 2 Level 1C imagery

I am hoping to derive a variety of vegetation indices for grasslands in Peru using Sentinel 2 data for one cloud free image in June 2016. But most of my indices are not in the range of the index. For ...
1
vote
0answers
46 views

Using LiDAR to identify coniferous and deciduous trees

Is it possible to use only LiDAR data to distinguish between mostly coniferous and deciduous forest? I have a LiDAR data from spring and summer, but they have different point spacing.
1
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0answers
26 views

Google Earth Engine unequal histogram values

I am creating histograms in Earth Engine of pixel values of cloud masked EVI from different years using Landsat 8. For each of the layers I create, I use an identical geometry to clip the output, but ...
1
vote
1answer
44 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 [...
1
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0answers
37 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 ...
1
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0answers
438 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 ...
1
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0answers
234 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 ...
1
vote
0answers
106 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 ...
1
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0answers
98 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 ...
1
vote
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 ...
1
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0answers
104 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 ...
1
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0answers
553 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....
1
vote
0answers
141 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, ...
1
vote
0answers
211 views

Why are Landsat-8 derived NDVI values higher than SAVI values?

I have calculated NDVI and SAVI vegetation indices for a landsat-8 image. I am unexpectedly getting higher values for the NDVI than SAVI. What may be causing these unusual results? NDVI=0.46 SAVI=0....
0
votes
2answers
56 views

How to define areas from certain NDVI values in QGIS [closed]

I downloaded LANDSAT images from 1985-2018 with Google Engine, 2 for each year. Now I want to know how has the vegetation varied over the years with NDVI, using QGis 3.6.3. Having calculated the index ...
0
votes
2answers
346 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:
0
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2answers
583 views

What is the index formula to calculate water stress index using multispectral sensor (Red, Blue, Green, Red edge, NIR)?

I am having a multispectral sensor with Red band, Blue band, Green band, Red-edge band and Near-Infrared band. I need to find water stress using these bands, is it possible to find and if yes what ...
0
votes
1answer
65 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 ...
0
votes
1answer
668 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 ...
0
votes
1answer
433 views

What are the spectral indices that use addition of Landsat 8 bands for finding vegetation?

NDVI is found out using the division of subtraction and addition of bands. Is there a simpler index for finding out vegetation(or other physical characteristic)? For example, DVI=NearInfraRed-Red is a ...
0
votes
1answer
29 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. ...
0
votes
1answer
104 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/...