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Questions tagged [ndvi]

Normalized Difference Vegetation Index is used to quickly identify vegetation and its condition in remotely-sensed data.

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NDVI Monthly Composites :: GEE :: EEException: Image.select: Band pattern 'NDVI' was applied to an Image with no bands

I am trying to create monthly composites of NDVI. But I am getting error. I have this code: def create_composites(ndvi, vis, band, view, layer_year, year): def monthlyComposite(year, month): ...
user14's user avatar
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Error trying to calculate the NDVI of about 20 cities in the USA in GEE

I am new to GEE. I am trying to calculate the NDVI of about 20 cities in the USA. However, I keep getting this error: Error: User memory limit exceeded. (Error code: 3) I don't know how to solve it. ...
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Calculating NDVI using OrfeoToolbox

Platform: Windows 11 Aim trying to achieve: I have downloaded some multispectral test data from OpenDroneMap (ODM) forum. The data is captured with DJI Mavic 3M. What I want is to analyze NDVI, NDRE, ...
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Error generating chart: Image.parseExpression: Expression contains undeclared variables: [max] for vci, and tci [closed]

I have a problem creating the chart and there is error message expression undeclared variables var geometry = /* color: #d63000 */ /* displayProperties: [ { "type": &...
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How to the image date/ metadata used when using the .median filter in GEE?

I am processing LST, NDVI, NDBI, & UHI data in a 1 year period. I used the .median filter function for filtering the dates. My question is, how do I know what images to use? I've tried the ...
primamuliaa's user avatar
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Does MODIS dataset (MOD09GQ) require atmospheric correction to calculate NDVI?

It took a dataset of satellite images with a high frequency of reception (1 day) to work. The work consists in studying the change in the NDVI coefficient at a certain site during the year. I took ...
senek's user avatar
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Cannot export NDVI map to google drive on Google Earth Engine

I am trying to export an image of NDVI before a wildfire to my Google Drive but it keeps failing and I am unsure of what the issue is. the variable burntsite is a polygon I drew. var prefire = ee....
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TypeError: Image data of dtype object cannot be converted to float

The main functionality of the script is to extract GeoJSON data, load it into Earth Engine, retrieve Sentinel-2 imagery, calculate the mean NDVI, and visualize the NDVI for each GeoJSON feature. My ...
Muhammad Waqas's user avatar
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Cloud Masking and Compositing Landsat SR Timeseries in GEE Python Colab - Fails to Export

I'm trying to create a seasonal (dry/wet) Landsat NDVI time series for multiple sites in an area over a span of approximately 30 years within Google Earth Engine's Python Colab. Each site will have a ...
Ally's user avatar
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Landsat NDVI Anomaly Google Earth Engine

I am interested in calculating Monthly NDVI anomaly using Landsat. My objective will calculate long term monthly NDVI with all Landsat collection 2 sensors. In this simpler example I am only using ...
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Mann-Kendall trend test on GEE returns empty band

I am using GEE to run the Mann-Kendall trend test on NDVI over my study area from 2001 to 2023. I want to show the NDVI trend for each individual month for the 22 years, which means January 2001,2002.....
Cinnamon roll's user avatar
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How to analyze NDVI time series data

I am analyzing time series data of NDVI within an AOI. Ultimately, I would like to plot the average monthly data in a box-and-whisker diagram. Here is the problem. The number of months with ...
aogorou's user avatar
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Convert irregular time series to regular for running bfast model

I have NDVI rasters extracted from Sentinel-2 with irregular time series over a year and missing data of July. I would like to generate the irregular time series to a monthly regular time series in R ...
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Extract, plot and export as a table a vegetation index time series from multipoint feature collection in Earth Engine

Reference is to a tread I posed years ago and was solved Extract pixel values from several bands of an image and export in a single table in Google Earth Engine The challenge now is to create S2 NDVI ...
Lollo's user avatar
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Issues with Clipping Shape of Sentinel-2 NDVI Image in Google Earth Engine Python API

I'm working on an agricultural analytics application where I need to generate NDVI images from Sentinel-2 data for user-defined polygon areas. The backend is implemented in Python using Flask and the ...
Maha Khan's user avatar
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Maps and graphs not rendered for NDVI-based variable using Google Earth Engine JavaScript API

I’ve written the code below (sorry if this is a lengthy block) to calculate ESPI which is annual mean minus monthly average standard deviation of NDVI. Though the code ran without any problem, maps ...
rez's user avatar
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Get the slope of a linear regression in Google Earth Engine

I have an image with 3 bands that represent the NDVI value from 3 different years: // Load Landsat imagery for different years var landsat2019 = ee.ImageCollection('LANDSAT/LC08/C01/T1_TOA') ....
Isa's user avatar
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Direct use of Sentinel 2 L2A imagery for vegetation analysis

I am working on my research to calculate the green vegetation in the study area using sentinel 2 L2A 10m resolution. Do I need to perform any correction or smoothing before analysis?
Monika Jirel's user avatar
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NDVI and variations

I'm trying to create a variation on an NDVI. However, the Landsat Imagery I have keeps doing this or this Even though the original bands load fine (here's an example) Anyone have an ideas?!
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Eliminating missing pixels in NDVI time series analysis by temporal gap filling with linear interpolation to get a smooth result

The code is running correctly but it doesn't give me a smoothened result. Anyone who can help me out? var startDate = '2015-01-01'; var endDate = '2023-12-31'; var images = sentinel.filter(ee.Filter....
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Trying to create mask to eliminate false NDVI numbers in GEE time series analysis using Sentinel data

It keeps given me the error that ndvi.gte is not a function, I shared my code below: var images = sentinel.filter(ee.Filter.date(startDate,endDate)).filterBounds(geometry) print(images); var ndvi = ...
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Large values while calculating on normalized difference indexes

I've encountered a problem while calculating NDDI index (NDVI-NDWI/NDVI+NDWI) in ArcGIS Pro for my bachelor's thesis. I'm working with Raster Calculator (the problem appeared in both Image Analyst ...
Macko01's user avatar
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Unable to compute graph in Google Earth Engine when trying to compute mODIS NDVI Time series analysis of a small region in Crete, Greece

I want to make a simple time series analysis of the past 8 years using MODIS data but I'm unable to compute the graph as I get the following message: Error generating chart: Collection.first: ...
Eppez's user avatar
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Extracting seasonal maximum from smoothed MODIS NDVI time series in Google Earth Engine

I am trying to extract the seasonal maximum NDVI value (01st June to 31st October) from 2000 to 2023, i.e., total 24 NDVI images. For that I have imported the MOD13A2 datasets in the Google Earth ...
CESCRA IARI's user avatar
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Erdas - Export LUT Instead Of Real Values

I am using Erdas 2022. I have NDVI index of an imaging, and after creating it, the view shows a LUT which is not the original pixels, which is essentially the automatic stretching of the program. I ...
Guy Yafe's user avatar
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103 views

Skewed NDVI values

I'm analyzing open-source NIR images with Python. I'm a novice to remote-sensing and have a doubt about my NDVI results. I calculate my NDVI like so: with rasterio.open(self.tif_path) as src: ...
Michael S's user avatar
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30 views

NDVI temporal analysis error in Sentinel

I need to do a temporal analysis of NDVI with Sentinel images from 2019 to 2023, using monthly composites and extract the NDVI value for random points created. However, it is generating empty data. ...
Paula Duarte's user avatar
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Projecting Landsat image correctly using Build Virtual Raster

I am trying to make one complete image using B4 images from USGS and another using B3 images to then calculate NDVI. The issue I'm having is a single image not lining up in the same projection (see ...
Aimee Calkin's user avatar
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Google Earth Engine Landsat NDVI

I'm trying to map deforestation using Landsat NDVI time-series. But unfortunately I can't find the data from 2022 - 2023, on the other side data before that year is available. Can someone explain me ...
MapperIndo's user avatar
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28 views

Google Earth Engine NDVI no value

I'm using GEE for NDVI (using landsat 8) but there is many holes in my image, can someone explain me what happened? here's the code // Function to mask clouds using the quality band of Landsat 8. var ...
MapperIndo's user avatar
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59 views

NAN String on Maxent

I'm using NDVI for one of my environmental layers, i got it from google earth engine and process the data using ArcGis Desktop. I already convert it to ascii and check there's some NAN in my data. ...
MapperIndo's user avatar
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NDVI calculation problem in QGIS

I have a satellite image with 4 bands, R,G,B,NIR. I have used the QGIS raster calculator to produce an NDVI - standard (NIR-R)/(NIR+R). I am expecting an output between 1 and 0, but the raster has the ...
Ixtlilton's user avatar
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107 views

Get monthly NDVI and NDWI median for a year, from Landsat collection Google Earth Engine (GEE)

I am trying to get NDVI and NDWI per month, based on the median of the images in one month. For this, I am using Landsat8 collection an year 2018. I keep getting empty bands for the var monthlyStats. ...
Valentina Bravo's user avatar
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24 views

Using same spatial resolution for NDVI and LST data in machine learning model

I am currently developing a drought forecasting machine learning model and this is my first time handling satellite data. Two of my data sources are the MOD13A1 dataset from Google Earth Engine for ...
Shrey Desai's user avatar
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Polygonize reclassified NDVI layer, how to remove sliver ploygons (QGIS)

I have calculated an NDVI layer, to create three categories (water, gravel, vegetation) that I can then polygonize. Now there is the issue that bright colored rocks and water have similar signatures, ...
beni 's user avatar
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1 answer
24 views

Why wont GEE upload my image to drive?

Im trying to export to my drive a cropped image of NDVI from the dataset 'LANDSAT/LC08/C01/T1_8DAY_NDVI', in the layer it shows perfectly but when i submit the task to upload it to drive it never ...
Nicanor's user avatar
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2 answers
184 views

Convert Landsat 9 Surface Reflectance product DN to surface reflectance values

I downloaded the Landsat 9 L2 imagery from Earth Explorer for the purpose of calculating NDVI. However, when opened in ArcMap 10, the pixel values are in the range of 7000 to 45000. I understand that ...
Tsaku Graham's user avatar
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22 views

Different statistical analysis for Classified Image

I have created a (1) Bamboo Index map using 2 satellite images i.e. Landsat-08 and Sentinel-02. The formula I used is: BI= (NDVI-NDMI)/(NDVI+NDMI) Where; NDMI is Normalized Difference Moisture Index. ...
Pushkar's user avatar
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88 views

Creating interactive chart in Jupyter Notebook using Geemap

This code applied the custom date to the x-axis. But I do not want this. I want to show the date on which the Image is taken by using "system:index" property of the Image. Also, This code ...
Muhammad Waqas's user avatar
1 vote
1 answer
106 views

Creating NDVI and Cloud Chart in Jupyter Notebook

I am trying to calculate NDVI and cloud pixel percentage. I have successfully done this but I am facing a problem in creating a chart of it in Jupyter Notebook, as I am new to Python so I tried ...
Muhammad Waqas's user avatar
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48 views

NDVI data for the UK

I am trying to download NDVI data to input into ArcGIS, I have used USGS however I cannot download any Landsat data for my area. I'm looking for a time period between 2000-2018 The specific area I'm ...
skye langford-brown's user avatar
1 vote
1 answer
63 views

Different NDVI Values for Landcover classes for Sentinel-2 and Landsat-8

I created a classified image of my study area using random tree classifier method as shown:- Fig 1: Classified Image of Landsat-8 Fig: Classified Image of Sentinel-2 I now want to classify image ...
Pushkar's user avatar
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1 answer
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Blank pre-1998 Landsat NDVI time series on GEE

I tried to generate Landsat NDVI time series for Fagge, Nigeria from 1993 to 2022 on Google Earth Engine but the output chart started from 1998 despite several items. Can you assist with the code? ...
Emmanuel Aweda's user avatar
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1 answer
22 views

Add feature ID to NDVI timseries in GEE

I have calculated NDVI timeseries for multiple points. I need to export a csv file that has the NDVI values, Date and ID or coordinates of points. The following script provides both the NDVI values ...
user21573937's user avatar
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26 views

Image (Error) Property 'NDVI' of feature '0_0' is missing

when I was working on classification for crop mapping to find maize fields, I faced the error. I made samples using geometry and named it trainingdata which indicate maize fields. Besides I tried ...
bahare bahmanabadi's user avatar
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1 answer
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Filter out blue patches in greenest pixel composite - GEE Quality Mosaic NDVI change image Sentinel-2

I am making greenest pixel composites from Sentinel-2 SR (using the quality mosaic tool in GEE based on NDVI). I then subtract two greenest pixel composites to get a change in NDVI image. These blue ...
Erin's user avatar
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Multiple Points showing up for for a given date after applying a Savitzky–Golay filter to smooth my data

I've been trying to draw NIR and NDVI data from LANDSAT and SENTINEL-1 data respectively, which can often be a little noisy. As such, I've been trying to apply the Savitzky–Golay filter available at: ...
user231178's user avatar
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1 answer
51 views

Does Landsat satellite image should have raster value to -1 and 1?

I am calculating the NDVI for Landsat-8 using the formula as shown below:- But the pixel value rendered is as shown below: - But the NDVI values need to be between -1 and +1 however, the value ...
Pushkar's user avatar
  • 83
0 votes
1 answer
40 views

Getting code to export monthly NDVI values

I am trying to export monthly NDVI values for 2007 for my asset 'M2007' which is a mangrove extent shapefile. I've been able to export following the same code, the monthly ndvi values for 2012, apart ...
Erika's user avatar
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1 answer
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I cannot export all image collection with image date for MODIS NDVI

While exporting images the namings are not setting properly with the image date. How can I solve the problem? I have attached the associated code: // Import the MODIS NDVI dataset. var modisNDVI = ee....
Naiem Sheikh's user avatar

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