Questions tagged [remote-sensing]
Collecting and interpreting information about the environment and the surface of the earth from a distance, primarily by sensing radiation that is naturally emitted or reflected by the earth's surface or from the atmosphere, or by sensing signals transmitted from a device and reflected back to it.
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How to resolve ENVI Flaash ACC error
I am currently preprocessing aster radiance at sensor(level 1b) images which I downloaded as .tif files, and can be accessed via this link from Earthdata. These are radiometric and geometrically ...
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Does anyone know where to find high res NDVI imagery [closed]
I'm wondering if anyone knows where to find NDVI imagery - preferable higher resolution- would planet work? (they seem to be paid so I'm not sure)
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Seeking recommendations for high-resolution satellite imagery of Sri Lanka for agricultural research [closed]
I am currently working on a research project focused on observing cultivated areas within Sri Lanka. For this project, I require up-to-date and high-resolution satellite imagery to accurately analyze ...
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Landsat 8 C2 L2 FOR NDVI
When I download Landsat 8 C2 L2 image from USGS and apply directly NDVI formula the value is ok it is in range -1,+1 while where I am applying scale factor which is (0.0000275)-(0.2) for each band ...
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Is it possible to find (or derive) a Land Surface Temperature product with a resolution of 50 metres or less?
I need to do a temperature assessment at a suburb level, hence the requirement for high resolution. The best I could find is 100m derived from Landsat, which apparently reaches a 30m res in the US. Is ...
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What is the difference between surface reflectance and top of atmosphere (TOA) reflectance?
I was told that during winter it is better to use TOA because SR is not good for winter. But I didn't find any files describing it. Can anyone explain the difference of these two and why they perform ...
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Calculate the error distribution of fractional abundance values between classes (a spectral mixture analysis issue)
I am trying to estimate the distribution of the under- and overestimation errors that I found in the outputs of a spectral mixture analysis (SMA), i.e. abundance fractional maps (AFM).
Specifically, ...
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Sentinel-2 QA60 band missing?
When performing cloud masking for Sentinel-2 images using QA60 band, I found that after February 2024, the QA bands of Sentinel-2 images are all "masked".
In this case, I can't perform cloud ...
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scp landsat not showing
why not showing landsat in preprocessing obtion?c
I cannot find Landsat in my preprocessing toolbar.
I have only preprocessing options of clip raster bands, image conversion, masking bands, mosaic ...
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How to create the fishnet grid in GEE using JS code editor?
I want to create a 10*10 pixel size grid for my AOI.
1 pixel = 10m
var cellSize = 100; // Size of each grid cell
// Get the bounds of the AOI
var bounds = aoi.geometry().bounds().coordinates().get(0)...
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Convert an .xml fil to .tif in ArcGIS Pro
Using ArcGIS Pro 3.3.
I downloaded Sentinel 2a data from Copernicus, a few months ago.
trying them out today and finding that I have XML and JPEG files, no TIFF.
this is what my Copernicus data looks ...
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Empty Metadata table in Semi-Automatic Classification Plugin of QGIS
I am working on Landsat 8 images using QGIS 3.36.2
When I want to convert clipped images to reflectance in Semi-Automatic Classification Plugin, nothing is displayed under the metadata table even ...
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Source for satellite images without geometric correction
I need satellite images for a university project and they must not have passed through geometric correction. So far the images I have found are already geometrically corrected in some form. Is there a ...
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Converting image data type from uint16 to uint8 using Python
I have a uint16 image, but when I want to convert this image to uint8 data type, I get bad results. I'm sharing my entry image and the result below. My image is a 3-channel RGB image.
original image: ...
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What does "post to post" mean?
For example, when someone talks about the "post to post" elevation error of a DTM, what exactly are they referring to?
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Strange stripes on Google Maps in the region of the October Revolution Island
On 2024-04-16 one can see strange stripes located roughly at 79.86317, 94.64563 in the region of the October Revolution Island.
What could be the source of these stripes in an end product?
I mean, ...
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Why if I spoof the position with GNSS Analysis MATLAB Google code,I get a spike of horizontal speed but it continue to be active while should be const
I'm using this GNSS Analysis Matlab Google code
to analyze the measurements performed via GNSSLogger app.
I was initially in Palermo,Sicily and tried to spoof to Rome. I get this
Horizontal speed ...
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QGIS plotting from a multiband raster in a ternary diagram
I am working on creating a (remote) superficial geological map using ASTER imagery in QGIS.
I have made several RGB composites including Abram's ratio and Thermal Infra red indices to aid in ...
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Random Forest error
I have tried a LULC classification using random forest algorithm in Google Earth Engine but error showing:
Layer error: Property 'B2' of feature '0' is missing.
My script code: https://code....
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Coregistration for training and validation
If I want to use a 30-m raster as an independent validation dataset for a remote sensing analysis of 10-m and 20-m satellite imagery bands, do I need to coregister the 30-m raster with the 10-m and 20-...
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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?
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Why are my calculated normalized difference indices maxima bigger +1?
I’m wondering about the results of my indices, e.g. the NBR maximum is +1.37 (see picture below),and as we all know the NBR (like any other normalized difference index) should be between -1 and 1…
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Understanding Landsat 8-9 Pixel Quality Assessment (QA_PIXEL) Value Interpretations
Table 6.3 here describes the Landsat 8-9 Pixel Quality Assessment (QA_PIXEL) Value Interpretations.
Value 54596 contains both "clear" and "cirrus". What am I to make of it? A pixel ...
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Is there a publicly available higher resolution equivalent to Landsat 8/9 TIRS?
I have a strong feeling the answer to this question is no. That said, I'd love to be wrong.
I'm looking to estimate land surface temperature at a higher resolution than the 100m bands (10 and 11) on ...
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Excluding 'No Data' Pixels When Counting number of pixels in an AOI with ERDAS IMAGINE
I'm working with Landsat imagery in ERDAS IMAGINE 2014 and have encountered an issue with 'no data' pixels within my Area of Interest (AOI). The AOI includes unwanted 'no data' pixels that are ...
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DIY Multispectral camera Rededge
I am trying to build my own multispectral camera using a Raspberry Pi, RGB camera, and Near IR Camera. My original goal was to measure the NDVI index. However I am now interested in the NDCI index as ...
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Implementing NDAVI in Google Earth Engine
I am attempting to use the NDAVI index to segment emergent aquatic vegetation from open water. I read in a paper that this could be done.
var point = ee.Geometry.Point([-122.292, 37.9018]);
// Import ...
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What do the values mean in surface reflectance/surface temperature bands Landsat 8/9 OLI/TIRS C2 Level 2?
I am trying to make a heat risk index using Landsat8 but I am having a bit of trouble with understanding the basics or operating remotely sensed imagery. I downloaded the band 10 of Landsat 8 because ...
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Landsat 8 - eleven bands and corresponding files
Landsat 8 zipped file downloaded via EarthExplorer consists of several files.
Which of the files correspond to the band 8, 9, 11?
LC09_L2SP_x_y_z_02_T1_ANG.txt
LC09_L2SP_x_y_z_02_T1_MTL.json
...
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On the edge of the swath and the reflection of the sun
In the Sentinel-2 image data, there is an overexposure near the water surface. I have examined several images and found that it is common to the eastern edge of the swath, so I think it is a ...
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Efficient way to handle large Sentinel - 2 imagery dataset
I need to automatically crop large number of polygons (~200K in a geojson file) from Sentinel-2 images varies both in extent (~30 tiles) and time (from May till August, say it's about 30 images) so if ...
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Use of convertmodis_gdal.convertModisGDAL
I tried to get ET and PET layer for MOD16A2 by using convertmodis_gdal.convertModisGDAL:
modisconv = convertmodis_gdal.convertModisGDAL(hdf, output, "(1 0 0)", 500, outformat='GTiff', epsg=...
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Getting NO2 concentrations for a given area
I am trying to get the NO2 concentrations at different coordinates for a specified area.
From the nc file downloaded from sci hub copernicus, I extracted the latitude, longitude and the NO2 ...
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Python reshaping issues of 13 band TIFF to run through Random Forest classifier
I'm having some issues that I'm seeking help with. I have a 13 band TIFF and a trained random forest classifier with 13 features that are in the correct order to match the 13 bands. I haven't made it ...
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Segment Anything Model integrated with QGIS
The Meta Segment Anything Model seems very powerful at image segmentation, and there are many development on remote sensing image segementation applications, Is there any QGIS plugins integrated ...
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How to Fix: Layer error: Computed value is too large in Google Earth Engine
I conducted a landcover classification, distinguishing between mangrove and non-mangrove areas. For each landcover type, I gathered fewer than 10 samples. I utilized Random Forest (RF) for ...
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How to produce spectral signature using SCP plugin for drone images
The SCP plugin can output spectral signatures of satellite remote sensing imagery. I'm wondering, has anyone tried to use the SCP plugin to output spectral signatures of drone-based imagery (for my ...
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Problems importing DJI Phantom images into QGIS
I am trying to import DJI Phantom 4 multispectral imagery into QGIS. I have imported the imagery but the images are not in the right location (showing near the coast of Africa when they should be in ...
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GEE Global Forest Change Hansen treecover and lossyear layers contradiction
In the Global Forest Change Hansen dataset, why does the layer lossyear shows several pixels as deforested in the year 2001 when the layer treecover2000 indicates that those same pixels had no forest ...
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Downloading photos from Google Street View and use then for QGIS Atlas
I am carrying out a remote sensing work (land use mapping of the Dakar metropolitan area based on sentinel2 images classifications).
In order to compensate for the absence of a ground campaign and ...
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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 ...
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Converting VICAR data to TIFF
I want to convert the VICAR data found at this ASU link
to TIFF that I can use in ArcGIS Pro.
How am I able to do this?
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Creating square polygons from two known diagonal corner vertices
Similar question to
How to make a square out of two points?-- I have a CSV file with coordinates for the bottom left and top right corners of multiple sampling plots and would like to make individual ...
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Downloading Sentinel-2 images: "offline products" in Copernicus Open Access Hub site
I want to download Sentinel-2 Level1C images for the specific dates. So I tried to download them from Copernicus Open Access Hub site. But I can't download since it says the product is offline,
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Monthly sentinel-2 Max and Mean NDVI, and B9 values extracted to CSV
When trying to run this code I get an error:
Expected Type: Image(unknown bands) actual type:ImageCollections
I would also like to maintain the ID column to be the ID column in my shapefile(labelled ...
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Converting Hansen Global Forest Change 'Forest Loss Year' into panel data structure
I downloaded the hansen deforestation loss year layer from the website (https://earthenginepartners.appspot.com/science-2013-global-forest/download_v1.7.html).
It is a single raster with one band. ...
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I want to test the statistical significance of the NDVI change in R
I have 20 Sentinel 2 satellite data for the period from 2017 to 2020, with 5 satellite scenes each for the months from May to September, covering one vegetation season. I am interested in whether the ...
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I want to apply Mann-Kendall test to NDVI of Sentinel 2 data in R
I have 20 Sentinel 2 satellite scenes from 2017 to 2020 with the months from May to September to cover the growing season. I calculated the NDVI of each scene and intersected it with my area of ...
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Unable to export time series from MODIS NDVI in GEE as transforming geometry into requested projection not working
I am trying to acquire MODIS NDVI (MOD13Q1 v061) time series using Google Earth Engine for certain locations for which I have the coordinates. My code looks as follows:
////////// Input
// Specify ...
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Difference of image and imagery in writing paper
Sorry I'm not sure if I should post this question here, or in the "English language usage" site. Because this is a question typically related to the remote sensing paper.
I'm writing a paper ...
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