I am working with Drone air images. These are geotiff images and clearly portray trees and buildings. I need to first classify the image according to land cover distribution, then need to remove the trees, grasses and buildings to get the original terrain model. I have another image of same area with elevation values and I need to reduce the elevation of objects over the surface.
I used ArcGIS 10.2 Spatial Analyst>Image Classification. I selected the Training Areas against my classification requirement and the generate signature file using automated toolset. I used this signature file for supervised classification and used Maximum likelihood for my classification.
The result of classification was awful. I found the big trees are classified as both grass land and trees as well as crops field also classified as big trees.
The image is RGB and it shows similar reflectance of big trees, crop fields and grass land. So, it is difficult for me to classify different classes separately to extract actual surface reducing tree height or crop height.
I am wondering if anybody has any suggestions regarding this issue.