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4 Replies and 1278 Views ENVI Classic question  1278  4 Started by  Deleted User I have recently started working with ENVI Classic as part of my undergrad research project. I work with Landsat 5 TM data and my goal is to use thermal band 6 (NYC location), convert raw data to actually temperature in K (which I have done already), and then perform unsupervised classification (done as well). My question is, once I perform K-means classification for example and get 3 classes (urban, water, vegetation) I cannot find the mean temperature for each class as my data disappears once t...
4 1278
26 May 2015 11:53 AM
1 Replies and 1823 Views PS Geocoding  1823  1 Started by  Deleted User Hello everyone, I am performing PS Interferometry analysis on a stack of Cosmo-Skymmed Images. When reaching the Geocoding step, the PS Map (.shp and .kml files) is properly generated providing the information I'm interested in. However, I have checked the Make Geocoded Raster flag in order to obtain the displacement velocity map as a raster, and It has not been created ( note I have also unchecked the Create Geocoded Shape). And, by the way, is it possible to make the PS map less dense It ha...
1 1823
26 May 2015 06:49 AM
2 Replies and 2016 Views summing pixel values for a raster file  2016  2 Started by  Deleted User Hello, I have a raster file where each pixel value represents the volume of a feature across a landscape. I want to find the total volume of the feature in my study region. So I would like to sum every pixel value in the raster file and have a single value which represents the total volume. Is there anyway of doing this in ENVI Thanks in advance!
2 2016
26 May 2015 05:50 AM
2 Replies and 1637 Views Change detection tool  1637  2 Started by  Deleted User Has something changed in the Change detection tool in the new version Is there anyway to refresh the steps to detect changes between images
2 1637
26 May 2015 04:36 AM
2 Replies and 1337 Views Creating Spatial Profiles in ENVI 5.0  1337  2 Started by  Deleted User Dear All; I am intending to create Spatial Profile that would extract the raster values underlying the polyline. I have found that there is a tool namely 'Arbitary Profile (Transect) that has been provided in ENVI 5.2 SP1 facilitates the user to generate such profiles. However, I am using ENVI 5.0 where I tried rigorously but didn't found such tool in it.
2 1337
25 May 2015 03:20 AM
5 Replies and 2379 Views Open AVIRIS data  2379  5 Started by  Deleted User Hello All! I am wondering how to open Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data in ENVI where all bands are displayed! Although in the .hdr file, it shows that my image includes 27 bands, from "open image file" only 3 bands are listed! On the list of "Open External File" I can not find the AVIRIS! Please help!
5 2379
22 May 2015 02:04 PM
3 Replies and 1513 Views how to use file with ".000"extensions  1513  3 Started by  Deleted User I have few spectrum files with extensions '.000', '.001' etc.. and their .text versions also. I want to convert them to .asd format. also some spectrums are of different scales and hence not being used for detection purpose. how to manipulate the scales of these spectras. I actually want to perform target detecting using those as target spectrums. does anyone have an idea how to accomplish that, please suggest.
3 1513
21 May 2015 05:09 AM
2 Replies and 1473 Views Feature Extraction, Segmentation  1473  2 Started by  Deleted User Hi all! I'm using the feature extraction tool and am wondering if there is any way to run the segmentation of an image one time and be able to save it, and open the tool again but not have to run the segmentation step again and just import it in the example based FE tool. So far, I haven't found and good options. Thanks!!
2 1473
20 May 2015 02:55 PM
4 Replies and 1623 Views thor target detection  1623  4 Started by  Deleted User while performing target detection using thor target detection for single file tool I am facing an error "SVDC:SVDcmp_d did not converge" and before opening viewer its giving "no signature matching routine has completed successfully" and its not generating any rule image. please help me to resolve this problem
4 1623
20 May 2015 05:05 AM
1 Replies and 1654 Views Error: No module called envipy  1654  1 Started by  MariM When working with the ENVI tools for ArcGIS, I get this error message trying to use a tool: "Error: No module called envipy" How can I fix this
1 1654
19 May 2015 08:18 AM
2 Replies and 1398 Views Help doing supervised classification using texture data  1398  2 Started by  Deleted User I have a panchromatic image, of which I created a texture map. I want to use this information to do a supervised classification. I was going to create three ROI classes: bare ground, buildings, vegetation. I've performed supervised classification in ENVI using spectral data but never pan data. More specifically I'm having trouble with my classification recognizing my ROIs in the entire scene. For example, I have if I use a texture map to identify buildings vs. trees. vs. ground in the ROI tool, ...
2 1398
15 May 2015 10:55 AM
2 Replies and 1917 Views Vegetation Indices - output doesn&39;t make sense.  1917  2 Started by  Deleted User Hello, Apologies if these are simple questions, I'm new to ENVI and struggling to understand much of the help online! I'd appreciate any advice on any of these issues. I am trying to calculate indices to look at vegetation damage/stress over time using landsat 8 images with the bands stacked. I've used both the band math and spectral index tools to try and calculate Enhanced Vegetation Index. In the band math tool I entered the expression (2.5*((B2-B1)/(B26*B1-7.5*B31))) where B1= red B2=NIR a...
2 1917
13 May 2015 10:13 AM
1 Replies and 1670 Views Error with FLAASH  1670  1 Started by  Deleted User &160;I am running FLAASH in ENVI 5.0 and trying to do atmospheric correction on airborne hyperspectral data. The data has level 1b radiometric corrrection applied and is in nWcm-2sr-1nm-1 unsigned interger. I have applied the band math float(b1) followed by converstion from bsq to bil as an input radiance image for FLAASH. However I am continiously getting the error: "ACC error: avrd: IDL error: POINT LUN: Negative position argument not allowed. Position -204215960, Unit 102" See bel...
1 1670
12 May 2015 09:23 AM
10 Replies and 4833 Views Calculating Proportion of Vegetation using NDVI  4833  10 Started by  Deleted User Hello all; I am facing problem to enter a simple syntax in ENVI's Band Math to derive proportion of vegetation. Pv =&91(NDVI-NDVImin)/(NDVImax-NDVImin)&932 How would I enter this expression in ENVI. I have NDVI raster with Min value of -0.445443 and Max 0.683279
10 4833
12 May 2015 04:26 AM
1 Replies and 1675 Views convert Image to image GCP to Map  1675  1 Started by  Deleted User I am georeferencing a series of images, to a common georeferenced airphoto base, via image to image registration. I will subsequently have to continue to georeference derivative images made from the original files (before georeferencing). I'd like to convert the saved ground control points file from image to image points, to image to map points, to free myself dependence on the original airphoto. Is there a way using ENVI to automatically extract the map coordinated for the image coordinate ...
1 1675
11 May 2015 02:31 AM
1 Replies and 1800 Views How to collect spectral samples from all pixels of a ROI  1800  1 Started by  Deleted User Dear All, I would like to collect sample spectra from each of the pixels of a particular ROI. Please explain me how to extract. When I tried I could get only the mean spectra of a particlular class (ROI). But for analysis purpose I need all samples of that ROI. Suggest me some ideas. Thanks in advance. Regards, Arun Prasad Kumar
1 1800
07 May 2015 12:03 PM
1 Replies and 1353 Views Listing Bands and wavelength  1353  1 Started by  Deleted User Simple question that I should know, but how do I list the bands and their wavelengths for datasets that I load into ENVI I have AVIRIS data loaded.
1 1353
29 Apr 2015 01:13 PM
1 Replies and 2036 Views spectral resampling to sensor resolution  2036  1 Started by  Deleted User I have a question regarding the options for spectral resampling in ENVI and I would like to better understand when ENVI does in the background. For an image with defined sensor type and defined wavelengths per band, I can perform a spectral resampling to a 'pre defined filter function'. These filter functions can be found in the envi install directory and seem to be identical to the sensor specific spectral response functions. What happens exactly computationally when I perform spect...
1 2036
29 Apr 2015 07:10 AM
2 Replies and 1528 Views Multitemporal series with Landsat 5 and 8  1528  2 Started by  Deleted User Hi, I understand that for creating a Landsat time series for vegetation analysis using Lansat 8 and 5, the radiometric of L8 should be scale to the L5, that is, the L8 radiometric resolution should be scaled from 16 to 8 bits. Is that correct how could I perform that in ENVI Thank you in advance!
2 1528
28 Apr 2015 01:44 PM
4 Replies and 1635 Views Viewing header in a ASTER .hdf file  1635  4 Started by  Deleted User Hello, I'm trying to view the header information inside an ASTER Level 1B .hdf file. I have been told that inside the header file will be information (specifically, I need to find the solar zenith angle at time of acquisition) necessary for me to calculate albedo and land surface temperature (LST). The ASTER .hdf file I'm using is here: http://e4ftl01.cr.usgs.gov//ASTER_B/ASTT/AST_L1B.003/2001.01.20/AST_L1B_00301202001180838_20110120003355_23051.hdf Any help is appreciated. Thank you. Jon
4 1635
28 Apr 2015 10:38 AM
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