Questions tagged [ndvi]
Normalized Difference Vegetation Index is used to quickly identify vegetation and its condition in remotely-sensed data.
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15 views
Extracting the time from Sentinel-2 ImageCollection to use in harmonized modelling
I am trying to run a harmonized modelling of NDVI values for a selected region of interest using Sentinel-2 Image Collection. The approach I am working on is fairly similar to the Landsat Harmonized ...
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19 views
Calculating Annual Mean NDVI for set of features using Google Earth Engine
I'm trying to calculate the annual mean NDVI for a set of polygons that are stored in a table in GEE. I want the annual mean for a series of years to be added to the table as new fields. I have the ...
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1answer
37 views
EVI or NDVI collection image download
Landsat 8 Collection 1 Tier 1 8-Day EVI Composite.
I continued with the starting codes given by Google Earth Engine. I tried to solve my work by adding code to the rest of these codes. However, it ...
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20 views
Calculating NDVI around point using ArcGIS Pro [closed]
I am using ArcGIS Pro.
I have latitude and longitude coordinates for 6000 people and I want to calculate an average vegetation exposure value based on NDVI at different circular areas around the ...
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1answer
23 views
Exporting EVI image on Google Earth Engine with visual parameters between -1 and 1?
I am having an issue with exporting an EVI image with the visual parameters between -1 and 1. On Google Earth Engine (GEE), using the inspector tool, the values are between -1 and 1, but when I export ...
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14 views
Mean monthly NDVI from Sentinel to CSV-files
I am trying to create monthly NDVI maps from Sentinel in Google Earth Engine. The script that I'm using is from things I gathered around the internet. When I try to download this to a CSV-file, I get ...
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28 views
Finding image overlap in Landsat images - Google Earth Engine
I am trying to construct a time series of NDVI derived from Landsat 5, 7 and 8 using the Google Earth Engine's Python API. To ensure the validity of this TS, I am harmonising the TM/ETM+ imagery to ...
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1answer
24 views
Calculating zonal statistics for each polygon in shapefile using GEE
I have shapefile of counties and want to calculate mean NDVI for each. I know reducing connected components and ee.reducer.mean can be helpful in GEE but it wants it as CSV for further analysis in R ...
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27 views
Apply function to calculate NDVI on list of images
I'm looking for a simple for-loop to apply a function to create NDVI images from an original list and save those in a new folder.
I've created a function and show how I would apply it on one image but ...
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1answer
40 views
Calculating NDVI vegetation area in GEE generates error
I'm trying to calculate & extract the vegetation areas country wide (TZA) using Sentinel-2 imagery, and getting an error when trying to print that area. I'm listing the code below.
var region =...
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15 views
Using Photo Monitoring plugin in a macro in Fiji (ImageJ)
I am trying to run a macro that will automatically open my 8 band geotiff, stack it has an RGB(false color with Red, Green and NIR) and at the end use the Photo monitoring plugin to create the NDVI. I ...
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1answer
35 views
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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21 views
Getting one image by month+year to export from MODIS NDVI using Google Earth Engine JavaScript
I previusly made a similar question to export one image with 12 bands for several years, Automate exporting one image by year for several years GEE in the previous one the images were from "MODIS/...
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26 views
Moran's I in Google Earth Engine
I am doing a project that is looking at NDVI in certain areas of Africa in Google Earth Engine. I want to take the areas where I have made an NDVI band and then calculate Moran's I so that I can ...
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39 views
Earth Engine: Combine time-series of NDVI from Landsat 5, 7 and 8, into one image collection and export CSV values
I'm working with 79 different research sites in Oregon where I need to extract the full time-series of NDVI values for specific areas around natural springs and then compare them to a corresponding ...
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2answers
83 views
Printing max and min values of Landsat NDVI time series to GEE console
I am trying to extract the min and max values of an NDVI time series and print those values to the console, so I could then subtract those values to determine the seasonal stability of an area. Most ...
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1answer
30 views
Creating NDVI time series graphs from buffered point (vegetation plot) locations in Google Earth Engine
I am aware there are a lot of similar questions to this on here like
Time series analysis of NDVI using Google Earth Engine
Creating NDVI time series from single polygon of shapefile using Google ...
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32 views
Visualizing and downloading Landsat 5 NDVI Composite images
I'm working with GEE (no so experienced), trying to download a series of Landsat 5 NDVI composite images. The thing is the code I have isn't showing me the images that I want to downlad afterwards.
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28 views
Extracting raster NDVI images for summer months over several years (GEE and LANDSAT)
I want to extract NDVI raster image that is including only NDVI band over a certain region (noted as point) for summer months over several years. I am working with Landsat 8 and the time frame is June,...
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6 views
Making 8-day composites from daily data in ENVI
I have daily data of NDVI in .tif format for 18 years and I want to make 8-day composites from it. How can I do so in batch processing?
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16 views
Print attribute value of a polygon with OnClick function GEE
I have a shapefile with many polygons and attributes (example "polygon_ID"). I would like to get the printed ID when i click on a specific polygon.
It would be a simillar function to the &...
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1answer
24 views
Quantifying mangrove condition over an 8 year period
Below is the script and I've also put an image of what it's meant to look like and what my image ends up looking like
// The Landsat 8 top of atmosphere reflectance data
var l8 = ee.ImageCollection(&...
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1answer
47 views
How to get whole image exported from Google Earth Engine?
I used the LANDSAT 8 TOA data to create an NDVI image. I want to export the image to my Drive. I have most of the code and it works, but I can't get the whole image in the export. It should cover the ...
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2answers
52 views
Counting pixel values of NDVI
I'm trying to calculate the amount of pixels with the value of 0.3 to 0.7 between two different rasters (each raster of a different year) to calculate the loss of green spaces trough time.
Is it ...
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1answer
68 views
Calculating Sentinel derived NDVI within a Polygon and exporting to a CSV in Google Earth Engine
This question uses code based off @Kel Markert https://code.earthengine.google.com/349615d7802d59f677181bef0badad9f
I am attempting to get a maximum monthly NDVI value from 6 small polygons over a ...
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1answer
40 views
Compute NDVI over each image in an image collection and export NDVI thresholded images
I want to compute NDVI for all images in Sentinel2 (less than 20% cloud cover) in an image collection comprising 5 years. Thereafter, I want to batch export the output as a binary TIF file where NDVI &...
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1answer
35 views
My TIFF files are placed on top of each other when imported to QGIS
When I upload TIFF images to QGIS, all of these are placed on top of each other. The files are "telling" me they dont have the right projection, but I have tried many (including the same as ...
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2answers
97 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 ...
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1answer
61 views
How to correlate NDVI and Land Surface Temperature in QGIS? [closed]
I'm looking for ways to correlate the NDVI values and the land surface temperature values that I have on QGIS. I'm kind of new at using these kinds of programs. I'm working on a thesis and for my ...
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15 views
Intersecting Floating Points within a value range to parcel boundary
I have an NDVI with values of -0.99 to 0.88. The raster is floating points with no attribute table. I also have farms as parcel polygons.
Using ArcMap or ArcGIS Pro, how can I intersect only the ...
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38 views
Quarterly composites for calculating NDVI and EVI
I am trying to create a code that could be helpful for making quarterly composites from 2013 to 2016 in order to calculate NDVI and EVI.
I have figured out this code:
var start = ee.Date('2013-01-01');...
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18 views
Landsat NDVI collections, are they cloud filtered?
I am wondering if the Landsat NDVI collections (e.g. https://developers.google.com/earth-engine/datasets/catalog/LANDSAT_LT04_C01_T1_8DAY_NDVI) were cloud-filtered before their creation? I know these ...
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0answers
38 views
Create Time Series Chart of NDVI (based on Landsat 5) of a National Park in Germany with Google Earth Engine
So this is my code so far:
My Questions:
How do I name the title and x-axis and y-axis? It isnĀ“t working with
.setOptions({title: 'NDVI Bayrischer Wald Landsat 5 1984 - 2013'}) unfortunately.
How do ...
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1answer
30 views
Why are my forest areas orange and non-forest areas green in Google Earth Engine?
I'm doing GEARS' 3rd lab tutorial on Remote Sensing in Google Earth Engine.
I calculated the NDVI of an area in Batchellor, Australia. The result is a black and white image so I added a color palette. ...
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1answer
150 views
Image.glcmTexture: Only 32-bit or smaller integer types are currently supported
IĀ“m using entropy and GLCM function of Google Earth Engine (https://developers.google.com/earth-engine/guides/image_texture). I want to use NDVI band, obtained from landsat 8 image band algebra:
//...
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1answer
41 views
NDVI out of range?
I have composed a mosaics of 3 images of Landsat 8 Surface Reflectance Level 2 for the bands NIR and RED. According to the Landsat Surface Reflectance Product Guide each band is supposed to be ...
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33 views
Landsat imagery corrections
I have downloaded Landsat collection 1 Level 1 imagery (Landsat 4,5,7 and 8) from https://earthexplorer.usgs.gov/. I would like to know that do we have to apply some conversions or corrections before ...
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1answer
34 views
Google Earth Engine Map Layer Incorrect Position
Having read the Google Earth Engine guide 'NDVI, Mapping a Function over a Collection, Quality Mosaicking' (https://developers.google.com/earth-engine/tutorials/tutorial_api_06) I am trying to compute ...
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0answers
32 views
Iterate through each raster for executing an equation to calculate index using Python
I am working with multiple rasters, and in need to execute an equation on each raster, and save them on a date-wise for each raster in an out specified folder. Input Rasters are as follows
"...
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10 views
How to get the maximum value of NDVI in GEEļ¼for anther way but reduceRegionļ¼ļ¼
sorryļ¼I tried to use this method to get the maximum value of NDVI, but all years are -1 to 1, which is obviously wrong. Is there another way?
var dict1 = cdl_image.reduceRegion({
reducer: ...
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13 views
Extracting NDVI scores over time for defined field boundaries
I am trying to do something similar to this post with the dataset "users/ryanhuffman/Training_Dataset_Trunc" and keep getting hung up on an error with the dictionary section of the code. For ...
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1answer
108 views
Problem generating NDVI chart in GEE
I'm new to GEE. I'm currently working on NDVI data analysis. So this is my code for MODIS NDVI. I already run the NDVI scale factor function and do the image collection, Divide by 10000, in images ...
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0answers
60 views
User memory limit exceeded (Google Earth Engine error) [closed]
I keep getting the "Error generating chart: User memory limit exceeded" error for my code: https://code.earthengine.google.com/b533573a22c93e3ce40697d807c2102d
I'm trying to generate an NDVI ...
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0answers
22 views
Filter NDVI polygon region Google Earth Engine
I'm trying to get the NDVI specs from a polygon region around SF and the Bay Area but the image isn't working. It is being displayed in a region next to the polygon or just comes out black
My code is ...
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2answers
67 views
I want to create NDVI of multiple raster using ArcPy
I have multiple raster data which are layer stack. Now I want to create NDVI of each raster data. I am stuck in the code, I developed a script but dose not generate any output.
import arcpy, os
from ...
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1answer
125 views
Output data of NDVI of multiple regions into table from GEE
I am using GEE for NDVI calculating. There are 150 more counties in USA. I am now stuck in outputting the NDVI ("interest" at code) of each counties listing with "OBJECTID" at the ...
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32 views
How do I produce a time series of the NDVI with Landsat composites with Google Earth Engine?
I am trying to obtain a yearly time series of the NDVI values for a series of locations, specifically 82 random squared polygons. As I need the best temporal resolution possible, dating back to the ...
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1answer
163 views
Google Earth Engine: Working with imagery with “no bands” --how to select or rename a band
I am trying to perform various operations on MODIS datasets in google earth engine.
Every operation I try to perform is prevented by the requirement in code to select a band to work with.
This ...
2
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2answers
97 views
Calculating green roof area in QGIS
I am trying to detect green roofs in a city and would like to compute the total area of green roofs (also on a per roof basis).
I used a shapefile containing all roofs and used that to extract the ...
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0answers
37 views
Batch PyQGIS3 NDVI calculation yielding skewed outputs
In a previous post, I thought I'd cracked a problem running a script with a batch NDVI calculation on some 16bit unsigned ENVI .hdr data cubes:
from qgis.analysis import QgsRasterCalculatorEntry, ...
