| 03 Nov 2012 03:07 PM |
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Hi All,
Kindly, could anyone please let me know; is it possible in ENVI 4.8 to classify the vegetation density using an NDVI image according to the NDVI pixel value into (for instance) five categories, as following:
1. >0 to 0.15
2. >0.15-0.30
3. >0.30-0.45
4. >0.45-0.60
5. >0.60
Whereat all pixels in the first category take the value 1, all pixels in the second category take the value 2, and so on. Then please how to convert each mentioned category from raster into vector format.
Thanks a lot in advance.
Rafil
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MariM
Veteran Member
Posts:2396  
| 05 Nov 2012 08:14 AM |
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You would use a Density Slice (or what is now called Raster Color Slice in ENVI 5) to color the data ranges you desire. Then from the tool you can save it has a classification image.
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Deleted User
New Member
Posts: 
| 05 Nov 2012 03:51 PM |
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[QUOTE]MariM wrote
You would use a Density Slice (or what is now called Raster Color Slice in ENVI 5) to color the data ranges you desire. Then from the tool you can save it has a classification image.
[/QUOTE]
Dear MariM,
Many thanks indeed for your concern and your reply. Kindly, I hope you could let me know how can I assign value 1 to the first category, value 2 to the second category, and so on for the five categories of the NDVI image? As well as, after doing that how can I save the image as a new raster file includes five classes (categories).
Thanks a lot again.
All the best.
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Deleted User
New Member
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| 09 Nov 2012 03:30 PM |
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Once you have the classification image you can change the values of the classes in the ENVI header.
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Deleted User
New Member
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| 17 Nov 2012 12:49 PM |
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[QUOTE]ccooling wrote
Once you have the classification image you can change the values of the classes in the ENVI header.[/QUOTE]
Thanks a lot for your concern.
Kindly, could anybody please let me know how can I do that?
Any help will be highly appreciated.
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Deleted User
New Member
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| 19 Nov 2012 05:16 AM |
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[QUOTE]rafil wrote
ccooling wrote
Once you have the classification image you can change the values of the classes in the ENVI header.
Thanks a lot for your concern.
Kindly, could anybody please let me know how can I do that?
Any help will be highly appreciated.
[/QUOTE]
Open the header file with a text editor ( notepad, notepad++) and modify the values there.
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