envi feature extraction example based

toolbox -> example-based feature extraction -> enable preview 

change bands to NIR. Adjust scale and merge level

change class name to roof. enable show boundaries.

select some roofs from the segments

add grass, road, and concrete classes. Mark classes in different segments

attribute tab, auto select

algorithm tab -> select knn, increase Neighbours to 3

export raster

reference:

https://www.l3harrisgeospatial.com/docs/fxexamplebasedtutorial.html