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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Difference in Index Value for Sentinel-2 and Landsat-8
I am working on bamboo distribution mapping using Sentinel-2 and Landsat-8 based on Bamboo index on ArcMap. The formula used is i.e. (BI) = (NDVI-SI)/(NDVI+SI); Where NDVI equals Normalized Difference ...
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Maximum value for the GCI index is not correct
I'm working with QGIS 3.28.6 software. I have calculated the GCI index using a raster calculator. The formula used GCI = (NIR/GREEN)-1.
Unfortunately, the max values obtained are not in the range ...
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Getting time series from different locations for various indexes
I am trying to get the time series for different points of interest, but I can only get one point location. Many of the examples that are on the web use points that are created during the code but in ...
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Interpreting Green Chlorophyll Index vs NDVI
I am attempting to research the relationship between agricultural yields and household well-being, and I am using remote sensed vegetation indices calculated from LANDSAT images to do this. Whereas ...
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Compute kNDVI using R
I am performing a small test to calculate the RBF-kernel NDVI (kNDVI). kNDVI is a nonlinear generalization of the commonly used Normalized Difference Vegetation Index (NDVI). It is a novel spectral ...
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Google Earth Engine script change
I'm hoping to use the monitoring forest vegetation condition script in GEE. The example given is using the protected areas polygons but I'm trying to use this script across Brazil or a Brazilian state....
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Which collection data is suitable for calculating soil moisture index using Landsat 8?
I am trying to compute soil moisture index using Landsat 8 collection 1 level 1, but it seems that I am not computing it properly. My range is not 0 to 1, as it should. Values of my variables can be ...
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How do I interpret VNP13A1: VIIRS Vegetation Indices 16-Day date?
In Google Earth Engine, looking at the metadata for VNP13A1: VIIRS Vegetation Indices 16-Day 500m a start and end date is provided.
When converted to regular UTC date they are 2022-09-30 to 2022-10-08....
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Extract pixel NDVI and EVI values of different points in Google Earth Engine
I have around 50 field plots (20m x 20m). Now I am trying to extract the pixel NDVI and EVI values of these locations. I want to extract pixel values of my plot locations from the NDVI and EVI layers ...
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Computing vegetation indices using scikit-image: "Divide by zero" warning prevents Red Green Index calculation
I am attempting to locate all green pixels in an image by converting vegetative indices using the scikit-image module in python. However, when I try to compute the Red-Green index, I get the following ...
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Can we do soil analysis for Nitrogen using remote sensing without field data for validation? [closed]
Background:
Remote sensing is used for monitoring land cover change and for monitoring vegetation etc. In addition to that, it is used for soil analysis (alterations in soil properties) as well. There ...
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LANDSAT 7 Surface Reflectance Missing Data For Large Swaths of Area
I am attempting to calculate the Green Chlorophyll Index across districts in Mali during the growing season(5/1-10/1) for the years2010 to 2019. I use Landsat 8 Surface Reflectance data for 2013-2019(...
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Calculating vegetation indices NDRE AND RECI using Sentinel 2
I am trying to calculate NDRE and RECI using Sentinel imagery ON ArcGIS software . For RECI( RED EDGE CHLOROPHYLL INDEX) the formula is (NIR/RED-1).
Can you tell me which band to use in order to ...
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Error: ".filter is not a function" [duplicate]
I'm trying to create a GUI on Google Earth Engine Javascript API to calculate vegetation indexes and plot them on a chart. I'm getting the error l8.filter is not a function in the line no. 316 where I'...
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Error: "l8.filter is not a function"
I'm writing a code to calculate vegetation indexes and plot charts for each index. In the same script I've added the code to make a GUI for the same.
I'm getting the error:
Error: "l8.filter is ...
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Masking non-vegetation areas in image
I'm having a little trouble masking non-vegetation areas in my images.
I'm using Sentinel-2 images, and I have land use and cover across my country (Brazil). To this end, I reclassified this land use ...
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How to define a function that uses absolute value on GEE?
I want to define a function for an index MMRI using the formula given below
I'm relatively new to JS and I'm having trouble defining it correctly.
First, I defined NDVI and MNDWI. This works fine.
...
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Calculating average NDVI pixel-by-pixel
Ok, I have loaded a .tif file using python3. I calculated the NDVI by making calculations to the different channels of the .tif. I marked an area where I want to calculate the average NDVI. The ...
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GEE: Structure Insensitive Pigment Index time series for multiple polygons
I am trying to calculate the Structure Insensitive Pigment Index (SIPI) using MOD13Q1.061 Terra Vegetation Indices 16-Day Global 250m. More specifically, I would like to get a time series for multiple ...
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How can I extract monthly average value from the Leaf Area Index (LAI) of set of points?
I'm trying to get the monthly average value of the Leaf Area Index (LAI) between 2016 to 2019 from a set of sample points (n = 25) imported via Assets. However, when exporting the LAI values extracted,...
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Vegetative index returning impossibly high values
I am attempting to calculate a vegetative index from a mask layer for vegetation in a GeoTIFF image. The vegetative index is calculated simply as (r - b)/r on all pixels such that r !=0 and that ...
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Mapping salinity indices to pixel values
I have studied papers related to Soil Salinity indices that include equations such as this paper here.
What I try for many days to find out, is how the increase or decrease in a Salinity Index is ...
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Vegetation classification for aerial photography in QGIS
What I need to do is to use QGIS, for vegetation classification of some older and newer
Aerial Photography. In the past we have used ERADS Imagine but I have seen that there is some plugin developed ...
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Google Earth Engine calculation of new Index NDRS
I want to calclulate this index in GEE. I managed to calculate the DRS, but I do not understand how to calculate the NDRS. Can you help?
https://code.earthengine.google.com/?scriptPath=users%...
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Calculate and extract layer of NDVI change in Google Earth Engine
My experience and expertise in Google Earth Engine are super low. My study area is Sundarban, Bangladesh. I have 2 NDVI from 2 years (2016 & 2017). I want to find the vegetation change by ...
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Calculating change area using NDVI in Google Earth Engine JavaScript API
I am new to Google Earth Engine and JavaScript. I am trying to visualize and calculate the changed area from the NDVI of 2 years (Landsat 8 surface reflectance).
Can anyone help me to extract the area ...
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Extracting NDVI value for GPS points - how can I extract NDVI value for specific date and time for each GPS point?
I am quite new to GEE and trying to extract the NDVI value for a set of GPS points (X, Y, and date). I have constructed my NDVI layer and am able to obtain NDVI values for my points, however the date ...
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Modified Chlorophyll Absorption Ratio Index (MCARI) vs Green Chlorophyll Index (GCI) in a desert
I am using UAV multispectral data to compute different vegetation indices. Both of these indices were computed with the purpose of seeing/assessing the chlorophyll content, thus indicating if the ...
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MSAVI vs NDVI for deserts
I calculated NDVI (Normalised Difference Vegetation Index) and MSAVI (Modified Soil Adjusted Vegetation Index) for a desert environment, where most of the vegetation is shrubs with some trees using ...
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Getting error computing VCI in Google Earth Engine
I have tried to use this code:
https://code.earthengine.google.com/?scriptPath=users%2Fjohanneswilk%2Ftest%3ATest_13%20MODIS%20VCI%202
but there is the following error message:
Line 170: MonthlyMAX....
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GEE- Calculating Burned Area Index for Sentinel 2 (Filipponi et al. 2018) but getting binary result than index range
I am trying to calculate BAIS2 index for sentinel-2 collection over a study area in Google Earth Engine. I tried to create a function using expression but end result is binary image rather than index ...
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Indices similar to EVI for vegetation health analysis using UAV multispectral data
I know NDVI is the most commonly used index to start with vegetation health analysis. I am looking for other indices that can be calculated when the available UAV imagery has NIR, Red, Red Edge, Blue ...
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Expression for Modified Triangle Vegetation Index 2, Landsat 8
I am trying to run the index. In order to get it, I'm using raster calculator. Wrote the expression, but it's not coming rightly.
Could one check and revert whether the expression is right?
((1.8 * (&...
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Python - Calculating Burned Area Index results in empty plot
I've followed this tutorial to calculate the dNBR Index, using the given sample tif files which contain a burned area. My results were as shown on the tutorial. So far so good.
Then I tried to ...
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Google Earth Engine: calculate percentile rank in ee.ImageCollection
I am trying to calculate the Vegetation Productivity Index sensu copernicus in Google Earth Engine, which requires estimating the percentile rank. I haven't found any lead so far on how to do so, does ...
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Google Earth Engine - error in function to plot seasonal vegetation index for a region using MODIS data
I am trying to create a function to calculate the average Vegetation Condition Index
((mean NDVI of individual year)-(min NDVI from full period)) / ((max NDVI from full period) - (min NDVI from full ...
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Standardizing data over time (not space) in ArcGIS Pro 10.8?
I am trying to standardise Standard Precipitation Index data and Vegetation Health Index data over time on a 0 to 1 scale. I was previously using the fuzzy membership function to standardise the data ...
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Writing mathematical expression in Google Earth Engine
I am trying to run the expression below in Google Earth Engine to calculate Index-base Built-up Index(IBI)
var ibi = l8compositeMasked.expression(
'(2*SWIR/(SWIR+NIR)-((NIR/(NIR+RED))+(GREEN/(...
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Computing Excess Green Vegetation Index (ExG) in QGIS [duplicate]
I have to process the image for Sugarcane row detection and extraction.
Sample image is accessible from the link: https://github.com/AndresHerrera/croprows_generator_pa_v2/tree/master/droneimages
I ...
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Vegetation indices extraction from RGB images
I have been working on the project to classify crops as health or unhealthy. For this task I have taken the open source dataset from the the website https://www.sensefly.com/education/datasets . It ...
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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 ...
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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.
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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, ...
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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 ...
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Habitat Fragmentation Index calculation
What is the correct plugin/function to calculate a Habitat Fragmentation Index in QGIS (I use the 2.18 version) or FRAGSTAT starting from a vector layer?
I suppose that, first, I must convert the ...
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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 ...
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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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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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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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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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