Questions tagged [envi]
A remote sensing and image analysis software package produced by Exelis Visual Information Solutions (Exelis VIS).
291
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Color correcting/balancing for mosaic hyperspectral raster images
I have two rasters (hyperspectral images with 810 bands). I need to mosaic them, and I am doing it in ArcMap using Data management tools>Raster>raster dataset>create raster dataset>mosaic. ...
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34
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Problems trying to intersect two shapefiles
I keep having problems trying to intersect two shapefiles.
One of them is a normal file that I downloaded from geoamenagement.com. The other I created by using the classification protocol tool on an ...
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Converting SPOT 4 level 1A from TOA reflectance to Surface Reflectance in ENVI
I downloaded the SPOT scene Level 1A: Reflectance at the top of the Atmosphere, not orthorectified to use in land use and land cover mapping applications. I would like to convert them to Surface ...
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113
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Mosaic different data Sentinel-2 L2A image with color difference
I have downloaded two L2A level sentinel-2 images at 2022-09-05 and 2022-09-07 from scihub. After subset and resampling on SANP, I used seamless mosaic in ENVI to mosaic the two scenes, and I found ...
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RPC sensor model coefficient auxiliary data structure
I am part of a college team building a hyperspectral small satellite (3U). We would like to use ENVI's orthorectification module to do ortho. However, we need to generate our own RPC or sensor model. ...
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Using one set of ROIs to classify multiple raster layers in ENVI?
I am attempting to run a SAM classification on an airborne hyperspectral dataset with six total flight lines, and the files are too large to mosaic before processing. Is it possible to create an ...
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48
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NDVI value from different download sources
I downloaded the Level 2 image of landsat-8 in GEE and calculated the NDVI value in ENVI. At the same time, the Level 1 image of the corresponding date was downloaded from the USGS, and the NDVI value ...
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116
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Error during FLAASH Atmospheric Correction
I am trying to carry out Atmospheric Correction for LISS4 data using FLAASH. Since LISS4 is not available in the sensor list of ENVI, I have made the filter function file using the spectral builder ...
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73
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Digitizing photographs of a map
Is it possible to digitize the photographs of very old maps, having no co-ordinates. The photographs are exactly like this. If possible, could somebody tell me how to proceed? I have access to ArcGIS ...
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344
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ENVI error class_doit: An error has occurred during processing Error: "LA_LUDC: Singular matrix encountered, STATUS=2." The result may be invalid
I do a Maximum Likelihood Classification in ENVI 5.3. But after the process read the ROI, then appear pop up "ENVI error class_doit: An error has occurred during processing Error: "LA_LUDC: ...
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Extracting spectral signatures from ROI using ENVI5.3
I used ENVI's Band Math functionality for calculating a certain index to find out the dominance of a mineral. The output is one monochrome band as seen below, I really need your help to learn how to ...
user168625
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636
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Opening ENVI file in R gives error
I'm new at using GIS with R and I'm trying to open an ENVI file containing hyperspectral data following the suggestions from this post https://stackoverflow.com/questions/57474186/r-how-to-read-envi-...
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203
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Converting NTF to TIF using ArcGIS Pro in order to run FLAASH Correction
I received worldview 2 files but some are in the .ntf while others are in the .tiff format. I am able to work and FLAASH the files that are in the .tiff format but I am unable to FLAASH the .ntf files....
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Correcting effect of solar elevation angle in tagged areas for Landsat 8 L1T images using ENVI
Someone said the L1T images did not correct the effect of solar elevation angle.
I want to know how can I get the parameters for doing such correction in ENVI?
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394
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Converting ENVI file to TIFF using ArcPy
I have ENVI files one ASCII file .hdr and a flat_binary raster file which is a file without an extension
I'd like to convert them to TIFF files
These are the steps I followed:
Rename flat_binary ...
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205
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Extracting NDVI values from hdr file
I have a dataset of hdr files of MYD13A2 MODIS product including 4 bands NDVI, EVI, quality, and reliability.
I want to extract the NDVI values for a group of points; I have the geographic coordinate ...
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95
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Getting pixel values from lat/long values using ENVI
I am using ENVI software to process satellite image. I have two images from two different satellites and I want to get the value of the same point in the two images. I got random points from the first ...
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Designing a Low Pass Filter
How can I design a similar Low Pass Filter as given below which takes into account only 4-connectivity and ignores the pixels that complete 8-connectivity?
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LPF and HPF filters in ENVI
Since we know about convolution filter in image processing, it is basically a matrix applied to an image and a mathematical operation comprised of integers and it works by determining the value of a ...
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44
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Spectral signatures difference between a raw image and an atmospherically corrected image
I did atmospheric correction of Landsat 5 image by Quick atmospheric correction method(QUAC), now I want to compare atmospheric corrected spectral signatures from ENVI QUAC with the input spectral
...
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156
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Difference between two atmospherically corrected Images
I corrected Landsat 5 image with two different methods, first atmospheric correction through calibration (means converting raw image into radiance), second atmospheric correction through QUAC ...
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180
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Mosaic multiple 7gb TIFF into one big TIFF
I have data of 10 sets each with 361 channels in format of ENVI.
Each set contain:
7gb format-less file (BSQ #UPDATE)
2.4gb .ENP file
9kb .HDR file
I try to mosaic all of them in one big file.
What ...
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693
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GeoTIFF to ENVI GDAL translation causes rotation
I have a GeoTIFF(you can download it here ~16MB) which I want to convert to ENVI raw. I'm using this GDAL command:
gdal_translate -ot UInt16 -scale -of ENVI -outsize 1025 1025 dgm1_32372_5680_2_nw.tif ...
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185
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Cloud Shadow interferring with NDWI Analysis
I'm working on surface water identification in Northern Kenya. I'm using Landsat 5TM and Landsat 8OLI data in ENVI 5. I've masked clouds using the QA band (although have also tried the fmask tool- ...
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204
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ENVI fmask Error for Landsat 5 data
I'm trying to mask cloud cover of multi-spectral Landsat 5 image containing bands 1-7 that have been preprocessed using dark object subtraction and Landsat calibration.
I am using the fmask tool in ...
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885
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Merging 7 Satellite Images into 1 Image
I want to join 7 images [that is in .tiff] and merge and than subset the area using shapefile. But i am not able to merge it. I have loaded the images as raster layer and than merge it Using Qgis and ...
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Rescaling MNDWI to normalize
This statistic report shows the scale after done the MNDWI index process by using software ENVI 5.1.
Normally expect result have to be -1 to +1 scale.
How to get which scale?
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49
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FLAASH produces weird peaks
I am applying FLAASH to atmospherically correct and convert to reflectance a hyperspectral image acquired by our airborne system. The problem is that FLAASH (using ENVI) outputs an image where all ...
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114
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Enhance Vegetation Index ( EVI ) equation in ENVI IDL [closed]
I'm using ENVI 5.3 to find EVI, when I'm applying the equation it doesn't run, anybody can provide me the exact equation or formula for running the index. For more clarification, I'm using Landsat 8 ...
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340
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Map info extraction ENVI header
Does anyone have any idea about getting the map info from an ENVI header file?
This is my file.hdr as shown in the text editor:
ENVI
description = {
C:\xxxx\yyyy\Desktop\filename.}
samples = 36000
...
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168
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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 ...
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Is there a Post-classification Majority Analysis feature on Google Earth Engine (Similar to ENVI)?
In ENVI there's a Majority/Minority Analysis function that allows you to to change spurious/"wrongly classified" pixels within a large single class to that class (it also allows you to enter kernel ...
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Co-registering multiple temporal orthomosaics?
I have multiple (19) orthomosaics of the same approximate region taken regularly over the course of a couple months with a UAV. Some, but not all, include ground control points we placed in the scene....
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280
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Scaling factor for MODIS (MY09GA 006 or MYDTBGA 006) product for timeseries data
I was using Modis data (MYDO9GA) product for my research and I was following this document as a user guide.
https://landweb.modaps.eosdis.nasa.gov/QA_WWW/forPage/user_guide/MOD09_UserGuide_v1.4.pdf
...
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182
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Converting ENVI grid to Esri shapefile?
I have build geographic coordinates grid for raster in ENVI. It can be saved in grd format only, but I need shp (shapefile) format for opening it in ArcGIS Desktop or MapInfo.
Does anyone know how ...
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3
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425
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Mosaicing of multitemporal Sentinel-2 images using ENVI
My aim is to combine several Sentinel-2 Level2A images of the same location/orbit number but at different dates of a year.
I would like to have different options to create that mosaicing (e.g., if ...
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956
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gdal_translate not recognizing file format [duplicate]
I am trying to convert a .dat file to a .tif file using gdal_translate. The .dat file comes with an associated .Hdr file of the same name with the metadata (these are geospatial data from SNODAS). ...
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613
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Planetscope images atmospheric correction
I have downloaded an image which is level 3B processed (so I already have surface reflectance), but my assignment is to compare the data values of the SR file with my results.
At first I applied ...
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69
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Stacking lidar-derived height raster as ancillary data for segmentation in ENVI?
I get a a black and white image after following these steps. Does anyone know why I'm not getting a color aerial image beneath the mask?
My setup consists of these steps:
I mosaicked several NAIP ...
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1
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247
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Preparing raster Image for correlation in ENVI 5.5
I am working with two raster image of the same location with the same extent, both projected to the same coordinate system and having the same cell size. I want to correlate the raster value on the ...
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2
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416
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Explaining ENVI equations?
Could you please explain the meaning of this equation:
(b1 le 0) * 0 + (b1 ge 10000) * 1 + (b1 gt 0 et b1 lt 10000) * float (b1) / 10000 b1.
What do ge, gl etc mean?
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Is it possible to convert the SPECPR spectra files in to envi readable format?
The SPECPR files available with USGS spectra files are readable using the plugins which are tested with envi. specially envi 4.5 and 4.8. how ever is it possible to convert the full spectrum of specpr ...
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425
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Landsat 8 Level 2 products. Converting Pan & Thermal bands to spectral reflectance
We have downloaded around 20 Landsat Level 2 Surface Reflectance scenes for our AoI. The processed bands available in the downloaded scenes are, as you people know - Aerosol,B,G,R,NIR,SWIR,Cirrus.
...
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875
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Read aviris data with python
I try for too ling to read the envi file in python. Normally this is very easy.
First, I extract necessary values from the .hdr:
for line in open("../../local_storage_only/aviris/...
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1
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996
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Make layer stacking in ENVI for Landsat 8
I downloaded Landsat image 8 and I made layer stacking for RGB layers in ENVI (Bands 4,3,2) to classify the land cover types. But the problem appeared when I conducted supervised classification.
I ...
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1
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159
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Specifying band combinations when loading LANDSAT MTL files in ENVI IDL?
I'm somewhat new using ENVI and have a very limited background in programming. I was asked to compile 12 RGB and NIR composites of LANDSAT scenes within a specific timeframe and would like to use ENVI'...
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346
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Pleiades atmospheric correction
I have phr1a and phr1b images (Pleiades) and I need to make atmospheric correction. First, I tried to do this by using Envi FLAASH. by the way, I tried also ERDAS atcor but there was also same ...
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413
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Planet filter file for ENVI atmospheric correction
I have 4 band Planet Scope multispectral imagery that I am trying to process in ENVI. It is the analytic data, so it is already radiometrically corrected. I have converted the .tif to a BIL, and ...
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655
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ENVI 5.1 - ANN Classification - Background was classified into one of the class
I'm new to Remote Sensing and I'm having trouble in ENVI 5.1 where the background was classified as one of the classes in the ROI I used, which is not right. How can I exclude the background or at ...
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942
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Radiometric, reflectance and atmospheric correction for Landsat 8 image
I am struggling with the pre-processing process for landsat8 imagery.
I want to use some indices (e.g. NDVI, SAVI, EVI, NDMI) and create a land cover map at the end using ENVI and ArcGIS.
As a ...
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