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2 Replies and 1493 Views Landsat Calibration in ENVI v5?  1493  2 Started by  Deleted User In previous versions of ENVI I was used to using the Landsat Calibration all the time: Basic Tools>Pre-processing>Calibration Utilities>Landsat Calibration I may be mistaken, but I cannot find the same in ENVI v5 Has it disappeared If not, where can I find it It is a very common tool to use!! Andy
2 1493
04 Dec 2013 04:25 AM
1 Replies and 1199 Views masking  1199  1 Started by  Deleted User I'm using version 5.0 and would like to mask out some areas of cloud cover and ocean. I think I need to build a mask and then apply it to mask these pixels out of a set of bands worth of data (ASTER bands 1-3). I tried creating a vector, saving it as an ROI and then trying to build a mask but I didn't have any "selected attributes for mask". Thank you for any input
1 1199
02 Dec 2013 03:35 AM
1 Replies and 1292 Views Acquisiton time at classification and runtime problem  1292  1 Started by  Deleted User Hi, I would like to ask some help in two cases because I'm clueless. In my College Thesis I would like to write about measuring hyper spectral image classification (all supervised) running times. The Acquisition time status in the .hdr file is always Unknown. The IDL function for the Acquisition Time is runs, but without any result (http://www.exelisvis.com/docs/ENVITime.html). The Activity Monitor only sees the X11 runtime resource usages. How could I measure the classification running times i...
1 1292
30 Nov 2013 02:49 PM
1 Replies and 1201 Views Detailes on ICA algorithm  1201  1 Started by  Deleted User I have few questions regarding ICA algorithm in ENVI 5.0. First of all is there any difference between ICA transformation accessed from Menu: Transform-> Independent Components and the one in the SPEAR toolbox My second question refers to the detailed description of the algorithm behind. I would be grateful if someone could shed some light on the Contrast Function option. What exactly it is referring to and how it affects the algorithm. I don’t want to use ICA as a black-box but the pro...
1 1201
28 Nov 2013 02:29 AM
1 Replies and 1258 Views Maximum Likelihood Classification and Unclassified Pixels  1258  1 Started by  Deleted User I am attempting to run a Maximum Likelihood classification using ENVI Classic and pixel-based ROIs. However, whenever I run the classification several (but not all) of my classes consistently are placed as 'unclassified' pixels. I have tried manually setting the threshold for all of the classes to 0, thinking it was possibly a problem with that, but the issue still persists. I thought maybe it was a problem with the scale factor, but why would it only be affecting 2 of the 12 classes And if...
1 1258
27 Nov 2013 01:21 PM
1 Replies and 1419 Views Transforming Worldview 2 image (in integer format) to byte format  1419  1 Started by  Deleted User Hi everybody: I am trying to do image incet in quick map (qm), however, I get the answer that "the image must be in byte format". My image is in Integer format. Can anyone advise me how to do it Thanks, Muhammad
1 1419
25 Nov 2013 05:52 AM
0 Replies and 1281 Views Soil Moisture from SAR  1281  0 Started by  Deleted User Hi, I would appreciate if anybody can share the indices (formula) to: Estimate the soil moisture from RADARSAT-2 data. RADAR vegetation index from RADARSAT-2 data. Regards, Partha Ghosh
0 1281
24 Nov 2013 11:56 AM
3 Replies and 3326 Views can ENVI process .ecw files?  3326  3 Started by  Deleted User Hi All, I have been trying to subset .ecw files using ENVI. but it somehow gives me an error: "Error: "Read_ECW: Error reading data." The result may be invalid." Now I am wondering whether envi/IDL can process .ecw file formats. Thank you very much in advance. Cheers, Tania
3 3326
21 Nov 2013 09:25 PM
1 Replies and 1402 Views FLAASH--  1402  1 Started by  Deleted User Hi-- OK, this one has been driving me mad for about 2 weeks. I'm using Envi 4.5, and successfully converted several subsetted ASTER files to reflectance about a month ago. For some reason, it no longer works--I have tried on 3 different machines. The error message I get is: ACC Error: Convert7 IDL Error End of Input Reached on File Unit: 0 ACC_Convert7 ACC_Hyper2 ACC_ACC ENVI_ACC_EVENT ENVI_FLAASH_PROCESSMANAGER IDLRTMAIN| $MAIN$ As far as I know, I haven't changed anything--I...
1 1402
21 Nov 2013 06:04 PM
1 Replies and 1146 Views Applying a classification model to another image  1146  1 Started by  Deleted User ENVI folks: Given a set of training points (shapefile) that overlap with, say, a single image, how do I go about taking the classification model (e.g. maximum likelihood) to a DIFFERENT image (e.g. taken on a different date), not one that the training data were extracted from On a related note: is it possible to extract training data from multiple files
1 1146
21 Nov 2013 11:11 AM
1 Replies and 1388 Views Endmember Spectra Table  1388  1 Started by  Deleted User In the Endmember Collection window in ENVI Classic, when I add spectra from a .sli file, the table does not show up. Instead it remains with the message "Drag and Drop Spectra Here" I know the spectra have been loaded because I can hit the "Plot" button the spectra I imported plot, but can't change the colors or see them in the table. Is there something I am missing Thanks, A
1 1388
20 Nov 2013 02:42 PM
0 Replies and 1289 Views Rule Image Classifier  1289  0 Started by  Deleted User Background: I'm working in ENVI Classic with Landsat 8 data corrected to reflectance with FLAASH. I created a stack including 7 Landsat OLI bands plus an NDVI image derived from the same scene. I subsetted it and then ran Maximum Likelihood classification and outputted the rule image too. I then tried to run Post Classification > Rule Image Classifier. I have negative values in the Rule Images for each of the 6 classes I created. Questions: 1) Are negative values okay to have in rule image...
0 1289
20 Nov 2013 02:00 PM
1 Replies and 1253 Views Accuracy assessment of a Land Use classification using ground truth data in ENVI 5.0  1253  1 Started by  Deleted User I am in the process of assessing the accuracy of a Land Use classification using ground truth point data in ENVI 5.0. The tool/option I find from the classification toolbox (post classification folder) is the “Confusion Matrix using Ground Truth image”. However, I have ground truth point data. Can anyone provide help on how to apply ground truth point data for land use accuracy assessment in ENVI 5.0 Thank you
1 1253
20 Nov 2013 02:15 AM
2 Replies and 1066 Views Unzipping ENVI Classic Tutorial Data  1066  2 Started by  Deleted User Hi: I am facing problem in unzipping ENVI Classic Tutorial Data.zip. I am using Mac OS X. When I click "Open with Archive Utility" it starts opening but I don't know where it is sending it OR what it is doing to it. Any help to solve this problem will be highly appreciated. Regards, Muhammad
2 1066
19 Nov 2013 09:17 PM
1 Replies and 1268 Views Save/Restore Display Group  1268  1 Started by  Deleted User How do I Save/Restore a Display Group (in ENVI Classic, it was called "Save Session to Script"
1 1268
19 Nov 2013 12:05 PM
0 Replies and 1095 Views Different results classifiying with ML with Envi 4.7 and Envi Classic (Envi 5 SP3)  1095  0 Started by  Deleted User I have been working with a Landsat 8 image (reflectance values) to create a land cover map.I have used the Maximum likelihood algorithm and a set of ROIS (6 classes:forest, agriculture, water, shrubs, infrastructures, water). I have used the same parameters for the algorithm (Scale factor: 1.00 and ProbabilityThreshold: 0.85). Using Envi5 SP3 (with the Landsat hotfix) or the Envi Classic I obtain the same result(with involves many unclassified pixels, as could be expected), but it is completely ...
0 1095
19 Nov 2013 05:47 AM
0 Replies and 1310 Views FLAASH output data  1310  0 Started by  Deleted User Hi there I,m Meisam from Tehran university of Iran.I used FLAASH for atmosphere correction but the reflectance output data at some cases are more than 10000. that mean's the reflectance is greater than 1 and it's note true. could you tell me where i have mistakes thank you very much
0 1310
18 Nov 2013 02:57 AM
0 Replies and 1258 Views FLAASH data download  1258  0 Started by  Deleted User Hi there I,m Meisam from Tehran university of Iran. I've read you're flaash tutorialPDF and I want to use the data that you used in this PDF(LandsatTM_JasperRidge). I can' find the data download link in this site. where can I download these files. thank you very much
0 1258
18 Nov 2013 02:50 AM
1 Replies and 1432 Views Extract all polygons of 1 region in ROI tool  1432  1 Started by  Deleted User Hello,Since I have different locations when selecting 1 region (attached image). In ROI tool table I can see it has (for example) 10/2282 in Polygons tab. What does the number 2282 mean Since each location of that region I chose have different size.Is there a way I can extract all pixel values and coordinates of all locations I draw in that region And read in Matlab for exampleThank you,Canadry
1 1432
17 Nov 2013 08:02 PM
1 Replies and 1296 Views landsat 8  1296  1 Started by  Deleted User hellog i want to convert my Landsat 8 image from radiance to emissivity values but i don't know what to put in assumed emissivity values, the default is 0.96 but i read a book saying that is better for geological data,anyone who can explain me the reason behind so that i know what to put inside, am dealing with vegetation
1 1296
14 Nov 2013 02:32 PM
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