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0 Replies and 1482 Views ROI random sample question  1482  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 1482
15 Apr 2013 10:16 AM
3 Replies and 2402 Views Error message  2402  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 2402
15 Apr 2013 08:39 AM
1 Replies and 1494 Views Gathering training data across images  1494  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 1494
11 Apr 2013 05:59 PM
4 Replies and 1672 Views VIIRS .h5 image in ENVI  1672  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 1672
11 Apr 2013 04:23 AM
2 Replies and 1206 Views Quantifying post-NDVI pixel values in ENVI  1206  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 1206
08 Apr 2013 01:56 PM
11 Replies and 1881 Views LDCM / Landsat 8 file open  1881  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 1881
08 Apr 2013 11:50 AM
1 Replies and 1360 Views SPOT-5 View Angle Definitions  1360  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 1360
04 Apr 2013 02:06 PM
1 Replies and 1554 Views new ENVI website...  1554  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 1554
04 Apr 2013 11:33 AM
2 Replies and 1437 Views Image Background Transperancy  1437  2 Started by  Deleted User Hi, How do I make the image background transparent in ENVI 5 Thanks
2 1437
04 Apr 2013 05:03 AM
1 Replies and 1331 Views Layer stacking  1331  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 1331
04 Apr 2013 02:24 AM
1 Replies and 1341 Views ENVI Tools for ArcGIS - Image Processing  1341  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 1341
02 Apr 2013 03:26 PM
1 Replies and 1231 Views Shapefile and ROIS  1231  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 1231
28 Mar 2013 05:49 AM
1 Replies and 1476 Views Eigenvalues Algorithm used in Histogram ENVI  1476  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 1476
25 Mar 2013 04:54 AM
2 Replies and 1731 Views ENVI directional filter  1731  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 1731
23 Mar 2013 02:37 PM
3 Replies and 1347 Views ENVI's ROI and IDL's ROI compatibility  1347  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 1347
22 Mar 2013 12:51 PM
1 Replies and 1863 Views Orthorectification and Google Earth  1863  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 1863
21 Mar 2013 12:28 AM
1 Replies and 1912 Views ENVI 5.0 JPEG world file functionaly seems to be missing  1912  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 1912
19 Mar 2013 11:51 PM
1 Replies and 1330 Views Coastline Overlay in ENVI 5.0  1330  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 1330
19 Mar 2013 02:52 PM
2 Replies and 1215 Views Prepocessing of AQUA  1215  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 1215
19 Mar 2013 06:10 AM
3 Replies and 1208 Views Confusion Matrix and Accuracy Assessment  1208  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 1208
18 Mar 2013 11:18 AM
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