Question - Simple Classification ENVI 4.7/5.0

[raonizanovello]

Hi GIS Area,

 

I just made this account wondering if is anybody here could help me making a simple classification on high resolution satelite imagery (GeoEye). The problem is that the parameters in the software are not so clear for me, both, unsupervised and supervised, and I haven't found any conclusive solution on the web.

 

The methods I've tried are the K-mean, which gives me a highly fragmented image, and also ISOData, the parameters were all executed in the default, the only thing I did was to change classes from 5 to 3, or in the ISOData case, 3 or 4.

 

The supervised class. asks for a ROI and EVF file, which I searched on the internet and didn't understand what was going on with these files. What I did was to make some polygons in the ArcMAP 10.0 and did a supervised classification just there, again, with a very fragmented result.

 

I don't think it is a very hard situation, my objective here is just to divide the landscape into 2 or 3 main "clusters" which is pasture, forestry, and in some cases, water bodies (as is the case of the image posted in the topic) The softwares I have available are ENVI 4.7 and 5.0.

 

If someone could give me at least a hint or something like that, I would be really appreciate.

 

The satelite image is available for everyone in the google drive in the following link:

https://drive.google.com/file/d/0B1zf2D-uJw4wYWxQLWh0MFhZa3c/edit?usp=sharing

 

 

Regards!

 

Raôni Zanovello

[nnico]

For supervised classification you must first create source objects for classification (chose samples from image buy digitazing them). So, you must digitaze samle polygong in ENVI by ROI or EVF (Envi vector file).

I thing this link will be usefull for you:

http://www.exelisvis.com/portals/0/pdfs/envi/Classification_Methods.pdf