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0 Replies and 1547 Views ROI random sample question  1547  0 Started by  Deleted User I am working on a land cover classification map. I need to divide the ROIs up for a k-class cross validation and am having difficulty determining a way to generate the random sample k-classes themselves without losing the ROI assignment to each individual class. For example, if I have 3 land cover classes that have ROIs created and 500 ROIs total, I want to divide those 500 ROIs into 5 randomly divided groups of 100, use 400 of them for the training of the supervised classifier and the other ...
0 1547
15 Apr 2013 10:16 AM
3 Replies and 2614 Views Error message  2614  3 Started by  Deleted User Hi experts, every time I try to open landsat-7 ETM data like this: File>open external file>Landsat>geotiff with metadata The scene bands appear in the available band list, but when trying opening any band I recieve the following error message along with a black image display: ENVI Retrieve Data: An error has occurred during processing Error:"Point_LUN: variable is undefined unit." the result may be invalid I need your help in this problem Thanks for all This is the metafile conte...
3 2614
15 Apr 2013 08:39 AM
1 Replies and 1586 Views Gathering training data across images  1586  1 Started by  Deleted User I'm currently carrying out a project for a class. I need to carry out a multi-temporal classification of two landsat scenes from Central America (both the same R/P). After some pre-processing I am now ready to classify, and I would like to use the same training data for both images as they are both corrected for atmospheric affects. Is there a way I can select training data pixel by pixel from both images For example, I have individually classified images in the past, but that makes change dete...
1 1586
11 Apr 2013 05:59 PM
4 Replies and 1795 Views VIIRS .h5 image in ENVI  1795  4 Started by  Deleted User Dear All, Is there any possibility to work with Visible Infrared Imaging Radiometer Suite (VIIRS) which are available in .h5 format Many articles say they used h5 browser but i am not able to find that in Code library. Please help me by sharing any possibility to open and work on these .h5 files. harisubash2002yahoo.com With Regards Hari Adhikari
4 1795
11 Apr 2013 04:23 AM
2 Replies and 1291 Views Quantifying post-NDVI pixel values in ENVI  1291  2 Started by  Deleted User Hi- I'm working with some high-resolution imagery in ENVI... I've masked it and run an NDVI analysis on it, and now I'd like to quantify the number of pixels in certain value ranges... like, for example, the number of pixels that are between -1 and -0.5, -0.5 and 0, 0 and 0.5, and 0.5 and 1. Does anyone know how I might go about this I'm not very experienced with IDL, but if there's no other way I could use it. Thanks! Emma
2 1291
08 Apr 2013 01:56 PM
11 Replies and 2050 Views LDCM / Landsat 8 file open  2050  11 Started by  Deleted User Is there a patch to open an LCDM (Landsat 8) image using the USGS MTL-txt file yet I am running ENVI 5.0 SP2. I have searched the Code Library and Forum but have not found this topic. Will this be supported in ENVI 5.0 SP3 I can open each TIF layer and stack the files, but I do love the MTL.TXT open feature for the TM and ETM images. NASA has released the first LDCM image at: http://landsat.usgs.gov/LDCM_DataProduct.php
11 2050
08 Apr 2013 11:50 AM
1 Replies and 1457 Views SPOT-5 View Angle Definitions  1457  1 Started by  Deleted User Hello, I was wondering if someone could define the SPOT-5 view angles and relate them to zenith and azimuth angles for input into the Advanced FLAASH Settings dialog box. Image Angles: Incidence = R20.27, and Orientation = 12.57 Thank you, Nick
1 1457
04 Apr 2013 02:06 PM
1 Replies and 1671 Views new ENVI website...  1671  1 Started by  Deleted User Hello, The new website has a great feel to it and generally looks good I think, but is it possible that not all posts were transferred over correctly When I googled some ENVI topic, I get a link to an Exelis website, but then the link is broken and takes me to the homepage. Is there any plan to fix those broken links. I think it'd be good because there's lots of useful info. Mike
1 1671
04 Apr 2013 11:33 AM
2 Replies and 1517 Views Image Background Transperancy  1517  2 Started by  Deleted User Hi, How do I make the image background transparent in ENVI 5 Thanks
2 1517
04 Apr 2013 05:03 AM
1 Replies and 1419 Views Layer stacking  1419  1 Started by  Deleted User how ENVI calculates the Sample Rate sub-images in the "Layer stacking" I want to Mathematics formulas that ENVI uses for this kind of calculation. thank you
1 1419
04 Apr 2013 02:24 AM
1 Replies and 1438 Views ENVI Tools for ArcGIS - Image Processing  1438  1 Started by  Deleted User I'm using the ENVI Tools extension for ArcGIS 10.1. How can I run a "calculate thematic change" without specifically using classification images In other words, how can I force an image with distinct classes to be seen as "classified" without having to run another classification on it
1 1438
02 Apr 2013 03:26 PM
1 Replies and 1345 Views Shapefile and ROIS  1345  1 Started by  Deleted User Good morning Last weeks i face a big problem and till now i haven't sove it yet. I am working on Landsat imagery and i start to create ROIS as shapefile in Arcgis 10. I design them and when i try to open them as ROIS (convert shp to evf and after as ROI) i see that on the same image i work in arcgis 10 to design the roi's, the polygon data are not in the same position, but have a shift effect of 2-3 pixels below. The strange is that in ENVI EX or in ENVI Zoom the data are on the correct posi...
1 1345
28 Mar 2013 05:49 AM
1 Replies and 1582 Views Eigenvalues Algorithm used in Histogram ENVI  1582  1 Started by  Deleted User When you compute statistics of an image in ENVI, you have option to calculate the covariance of that image too and at the end you will have Eigenvalue for each band. I would appreciate if you explain about the model of calculating this Eigenvalue. In IDL Eigenvalue computes based on (http://www.exelisvis.com/docs/EIGENVEC.htmlE_841667181_47274) and it is a complex number, how ENVI reports just a number as Eigenvalue for each band
1 1582
25 Mar 2013 04:54 AM
2 Replies and 1840 Views ENVI directional filter  1840  2 Started by  Deleted User Hi, I have a serie of jpg images on which i would like to apply various directional filter. So I used Envi to try various options, All worked fine. Now my problem is i have undred of images, and I would like for convinience and efficiency to write a code to do it. so question1: is anyone aware of an ENVI_doit function to call the ENVI directional filtering function from IDL cause I looked a bit but could not find anything.. question 2: i used David Fanning SHARPEN function, which worked fine...
2 1840
23 Mar 2013 02:37 PM
3 Replies and 1463 Views ENVI's ROI and IDL's ROI compatibility  1463  3 Started by  Deleted User Hi everyone, I was wondering if ENVI's roi and IDL's roi are compatibles between them; I mean, if I have an ENVI's roi, can I use it in a proper way with only IDL And viceversa How can I do this Thanks for the help, Álvaro.
3 1463
22 Mar 2013 12:51 PM
1 Replies and 1980 Views Orthorectification and Google Earth  1980  1 Started by  Deleted User We have Hyperion images which have been orthorectified. But, when we overlay it on Google Earth, using ENVI SPEAR tools, for two locations having the same latitude and longitude, there is no correspondence. Can anyone tell me why this is happening Thank you!!
1 1980
21 Mar 2013 12:28 AM
1 Replies and 2067 Views ENVI 5.0 JPEG world file functionaly seems to be missing  2067  1 Started by  Deleted User Envi 5.0 appears to no longer deal with JPEG images with .jgw world file sidecar files. In Envi 4.8 when opening a .jpg file when a worldfile .jgw sidecar file was present would ask for the projection which could then be selected. This seems to no longer be working. Is there a workaround for this problem Is there a way to edit the projection parameters after loadingAny suggestions Thanks Axel
1 2067
19 Mar 2013 11:51 PM
1 Replies and 1441 Views Coastline Overlay in ENVI 5.0  1441  1 Started by  Deleted User How do you generate a coastline overlay in Envi 5.0. Used to be able to do this from Vector-> Create World Boundaries Thanks
1 1441
19 Mar 2013 02:52 PM
2 Replies and 1319 Views Prepocessing of AQUA  1319  2 Started by  Deleted User I have a MODIS image that is still raw, directly downloaded from the satellite. The problem i have is how to calibrate it and convert from L0 to L1/L2. please can anyone assist. Thank you
2 1319
19 Mar 2013 06:10 AM
3 Replies and 1347 Views Confusion Matrix and Accuracy Assessment  1347  3 Started by  Deleted User I want to classify my hyperspectral images into six different classes using both supervised and unsupervised techniques. The problem is, I don't have a ground truth image. Can I generate the confusion matrix without the ground truth image Thank You!!
3 1347
18 Mar 2013 11:18 AM
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