A remote sensing and image analysis software package produced by Exelis Visual Information Solutions (Exelis VIS).

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1answer
644 views

Raster vs. Raster Scatter Plot in ArcGIS

I created two raster datasets from the same world view 2 image. One dataset is NDVI, the other is a normalized surface water index (NDSWI). I would like to create a scatter plot for a pixel by pixel ...
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7 views

How to figure out how many ROIs are saved the .roi-file?

I have some .roi-data with stored regions of interest which I created several years ago. Now I would like to figure out, how many ROIsfor each class are saved in that .roi file. Open the .roi in Envi ...
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12 views

What is layer stacking and masking out?

I'm very new to GIS. Can you tell me what is layer stacking and masking out means in ENVI software
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8 views

how to perform linear regression to ndvi and lst

I Have two images of NDVI and LST derived from Landsat 8 and want to calculate the linear regression for between them obtaining the dry edge and wet edge on it.
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1answer
467 views

Applying pixel reliability mask to time series MOD13Q1

I am working with a 23-band GEOTiff in which each band is a 16-day MVC MODIS NDVI image. The MODIS .hdfs include a "pixel reliability" image with the following values: [-1]: Fill/No Data-Not ...
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25 views

Is the radiance and reflectance required for landsat 7 and landsat 8 for urban detection

I am working on urban detection in a an area where roads are made by cutting the forest. I want to ask that it is necessary both radiance and reflectance? I am narrowing my question as: I want to do ...
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1answer
812 views

ENVI 5.2.1 How to do an Accuracy Assessment using test data from a shapefile

ENVI 5.2.1. From a .tiff image (4 bands) I created a Supervised Classification Maximum Likelihood .dat file. Now I want to perform an Accuracy Assessment using test data from a shapefile. I've tried ...
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1answer
71 views

PS/SBAS Processing of S1 in Envi Sarscape 5.2

I'm processing a stack of s1a images in PS. I am now running the inversion first step. In the progress bar, it is stuck at the 'preliminary candidates selection' for quite some time. I am not sure if ...
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7 views

Reprojecting Modis data using MCTK Aand MRT

I am trying to re-project MODIS product MOD15A2H Fpar product. I need my data to be georefrenced so That I can create ROIs and find pixel values. However, I am having trouble georeferencing the data ...
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2answers
212 views

ENVI to map composition

I'd like to print out 6 images in a single page. How can I do this using map composition tools in ENVI (6 images are year-to-year dynamic images with the same size and the same geo-referencing)?
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1answer
18 views

How to select a fixed dimension ROI in ENVI?

ENVI provides the freedom to select ROIs by drawing polygons etc. I want to clip a fixed size ROI, say 512 x 512 in size. Is there a way to do that?
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1answer
443 views

Opening an modis hdf file in Envi and Calibration

I have downloaded an modis hdf file.it is l1 and its name is MOD021KM ..I want to convert it to radiance.so I performed this steps in envi Open>EOS>MODIS selected modis hdf file.then I tried to run ...
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1answer
680 views

Open Sentinel-1 products using ENVI 5.3

Is it possible to open Sentinel-1 products using ENVI 5.3? GeoTiff Sentinel-1 images can be opened independently but I can't open the product (from its xml file) using ENVI. I mean, is SARscape ...
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3answers
47 views

substitute for landsat 7 for land classification?

I am doing a project where I need to do a land classification for a forest reserve in Honduras. The dates I need are 2005, 2010, and 2015. I'm good for 2015 with LS8, but I am having difficulty with ...
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2answers
1k views

building a water mask

I'm working with multi-temporal datasets from modis and had to do various vegetation indices. I ran into a problem now because there is a significant amount of water too, which skews the resulting map....
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0answers
23 views

Conditional statement ENVI

I am trying to do conditional statement in ENVI to calculate multiband image: result = (b1)^2 - (b2)^2 if (b1 eq 0) or (b2 eq 0) result * 0 else result * (result gt 0.0) Is there a way to combine ...
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1answer
18 views

ENVI Changes the Projection of the output

After I have finished my Object-Oriented Classification, I open my result in ArcMap and I see that ENVI changed my Projection. Now the images are really in different places.
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1answer
54 views

How to overlay Radiance (Top-of Atmospheric radiance) over Digital Numbers Image?

I am trying to process INSAT-3D images, which contain six different bands. I have to extract each and every band form the .h5 data file, so when I extract first band (MIR) band form the data set, I ...
3
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1answer
52 views

Differences in the longitude and latitude between a LiDAR DSM and an optical image

I've downloaded the UK's LiDAR elevation data (see below) in laz format for a specific region (Tewkesbury) from: http://environment.data.gov.uk/ds/survey#/download From that, a DSM (Digital Surface ...
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51 views

Setting background value transparent in ENVI 5

How might I set the nodata/background value as transparent in ENVI 5.0? I know that I can edit the header of the file and set the "ignore value" field, which I tried (setting the field to -3....
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0answers
16 views

Snapping vectors to vertices for ROI delineation?

I am trying to manually extract a set of ROIs in ENVI 5.0. However, I can't seem to successfully line up the vector to be flush with the boundary of the pixels, which means I don't have fine-tune ...
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18 views

Pan Sharpening with ENVI 4.7

An error "READU:End of file encountered. Unit 100" is realized when I tried to pan_sharpen a Quickbird multispectral(RGB) imagery with a panchromatic one. Any ideas on what might be causing such an ...
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1answer
63 views

Creating raster image using Shapefile in ENVI?

I have shapefile containing polygon boundaries and want to change them as a raster image in ENVI 5.3. Although, this could easily be done in ArcMap or other GIS software, however, I will have to ...
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1answer
51 views

How to extract single band from multi-band radiometry raster using R?

I am having trouble extracting single band from multiple multi-band raster. I have no problem doing it on single raster file. Is there a way to loop through all the raster images to extract a single ...
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43 views

Why rescaling disturbs Band Order of FLAASH derived Reflectance image?

I have derived Reflectance values (MS bands) by calibrating Landsat8 OLI using ENVI's FLAASH module. The outcome of the FLAASH derived Reflectance values are scaled by 10,000 (by default), The reason ...
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2answers
61 views

Reclassifying Landcover Raster in ENVI 5.3?

I have produced landcover raster using Landsat 8 OLI, Pansharpened image. The derived landcover classified image is placed below: Now, I am intending to reclassify this image to change its class ...
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21 views

Facing “unknown sensor error” in using Alos Polsar 2 (Geotiff format) at ENVI 5.3

For calculation of Radar Backscatter for Alos 2 (2015) whit Geotiff format via ENVI 5.3, I faced following error: "The target file does not appear to be a valid sensor type" The question is; how ...
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2answers
110 views

Installing Viper tools for ENVI?

How can I install the VIPER TOOLS plug-in (for Multiple Endmember Spectral Mixture Analysis) in ENVI 5.1 (and later ENVI versions)? I have failed to complete the process following the VIPER TOOLS 1.5 ...
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53 views

How to classify difference surfaces having almost similar Reflectance responses?

I am using ENVI 5.3 to classify a Region of Interest clipped from Landsat 8 OLI. I have already performed calibration of my DNs by transforming it into Radiance and derived Reflectance image using ...
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2answers
86 views

Removing black background in ENVI

I am trying to compare two DEM products ASTER and SRTM v.3, but the ASTER has the black background which i think will interfere with my analysis. I don't have access to ArcGIS where I can do this ...
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1answer
663 views

Enhanced vegetation index using ENVI 4.7 bandmath

I computed Enhanced Vegetation Index using band math in ENVI 4.7 software. The expression used was: 2.5*((float(b1)- float(b2))/(float(b1)+ (6*float(b2)) +(7.5* float(b3)))) BYTSCL(float(b1), min = -...
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4answers
12k views

Manually edit a raster to improve a classification?

I have a land cover classification derived from Landsat TM imagery - I created this classification using ENVI. I would like to edit individual and groups of cells in some areas of the classification ...
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23 views

Hydrocarbon Index in eCognition

I would like to use the Hydrocarbon-Index from Kühn, Oppermann, Hörig in eCognition. Formula for Envi: HI=2(float(b3-b1))/3+b1-b2 So I imported a Hyperion Dataset and try to create an arithmetic ...
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34 views

atmospheric correction using Envi FLAASH

I'm using FLAASH for atmospheric correction in envi. an error comes up as shown in the picture. Does anybody know what's wrong with that? It is difficult for me to describe the information in the ...
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27 views

abnormal DN value after atmospheric correction

I'm using QUAC for atmospheric correction in ENVI (with data after radiometric calibration), but all DN values are 0 in the result. Does anybody know what's wrong with that?
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2answers
2k views

EVI and SAVI indices for Landsat 7 and Landsat 8

I'm trying to run the indices Savi and EVI at landsat 7 & 8. About SAVI I read this from ESRI and explains very good this index. About SAVI I have a question, I will choose buy my self the L ...
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1answer
49 views

LANDSAT 8 Resolution too low for coastline difference measurement?

I recently extracted coastlines (for my master thesis) for a Bangladesh region for the years 2013 and 2014. Regardless of the method I used, the distance between the 2 coastlines was always the same: ...
1
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3answers
379 views

Open LiDAR DEM of the UK with *.asc extension

I've downloaded a tile of a freely accessible LiDAR DEM of the UK from http://environment.data.gov.uk/ds/survey#/download. But I don't know how to open it. The files inside have the *.asc extension. ...
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2answers
51 views

Modis MOD11A1 band math expression

I am trying to calculate the temperature of MOD11A1 and I can't find the expression of band math. How the expression temp < 273 could be written at band math?
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43 views

Inserting scale bar in ENVI without resolution loss

I am currently using ENVI version 5.3.1 and am trying to insert a scale bar to the image, in addition to the north arrow already provided by default. I have tried searching on how to do this with most ...
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2answers
114 views

How to spatial subset (clip) TerraSAR-X SSC data (.cos) using vector files and one of the softwares (ENVI, PCI Geomatica, Erdas Imagine, etc)?

I have SSC data of San Francisco which I have extracted their extent as a KML file using: SARscape > Import Data > SAR Spaceborne > TerraSAR-X Then through some operations in ArcGIS, I have ...
2
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1answer
124 views

Extract coastline as a vector from landsat 8 imagery?

I am trying to detect some sea level rise/fall for a specific region, from Landsat imagery. I went through the recommended methods of identifying water/land (MNDWI, AWEI, Bandratio 5/2, etc.). Now ...
2
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1answer
59 views

Converting an ENVI raster as point shapefile for editing in ArcGIS?

I have an ENVI raster with multiple classes inside. I tried to export this to a vector so that I can convert it to a shapefile in ArcGis (I want to manually edit/delete points in the raster), but the ...
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1answer
309 views

mosaicking and projecting modis land cover data MCD12Q1

I have modis land cover MCD12Q1 data .Its in the sinusoidal projection (.hdf native format ). I have to study the land cover characters from the data for which i have to convert them into .tif format ,...
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0answers
384 views

Conversion problem of projection of MODIS LAI from sinusoidal to geographic

I am trying to change MODIS data's (LAI) sinusoidal projection to geographic. Actually I did it. But when I reproject it by ERDAS, the output LAI raster moved about 10 km to west side of actual shape ...
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30 views

How can I find pixel spacing in azimuth and range and look angle from envi sarscape?

I have a quad-pol ALOS-PALSAR dataset, which I have read using Envi SarScape. Now I find to read the header or where the following information is written: pixel spacing azimuth pixel spacing slant ...
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0answers
25 views

How to make LISS-III image coloured

In order to study land use and land cover change from LISS-III images I want to see the image coloured (i.e. false-colour composite RGB) using ENVI 5.0. What is the procedure?
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102 views

Maximum Likelihood Classification in ENVI

I am a new ENVI user and I am trying to perform a supervised classification of a Landsat 8 image with the maximum likelihood algorithm. In order to run the classification, I have to insert a Scale ...
1
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3answers
652 views

Extraction of monthly image from two-16 day images?

I need to combine two-16 day NDVI image into monthly NDVI image. To do this, what kind of function and formula are used in ENVI, ArcGIS Desktop or ERDAS?
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64 views

How to sync ENVI image window with Google Earth Pro?

I am unable to find documentation explaining how to sync an view in ENVI with Google Earth. I am zooming in and out of a RapidEye image in ENVI for an object-oriented classification and it would be ...