1
vote
1answer
25 views

Creating training areas for parametric classifcation

I am creating a signature file for a supervised classification for a subset of a LANDSAT image. I know what classes I would like to create, and have identified ideal areas for training. However, I am ...
1
vote
0answers
56 views

Importing GPS coordinates to extract multiple DN values in ERDAS

I have a set of GPS points (stored as a csv for now) and would like to import these points to ERDAS to find the DN values associated with each location. I am able to import a SHP to ERDAS but the ...
2
votes
1answer
863 views

Open Source Alternatives to Erdas ATCOR

I have been using Erdas ATCOR for atmospheric correction of ASTER imagery. What opensource options exist for atmospheric correction of ASTER Level 1B products? I'm primarily interested in converting ...
7
votes
1answer
239 views

How to produce a vegetation stress map utilizing the spectral blue shift of the red edge?

I am interested in mapping vegetation stress utilizing the blue shift to the red edge phenomenon in remote sensing. The figure below shows the expected change in reflectance of green leaves under ...
4
votes
2answers
155 views

What Information Does the Blue Band Provide?

I am playing around with ERDAS and was implementing image difference on two rasters separated by interval of time. I was using a blue band raster and I created a default threshold for percentage ...
6
votes
1answer
322 views

How to remove clouds in High resolution Imagery(.5 mGeoeye)

i have imagery with high resolution .5m, large parts covered with clouds,so it's obscure many urban areas. thank you.
3
votes
1answer
301 views

Cloud and Snow Differentiation

I am doing unsupervised classification of a mountaneous terrain and I have used 500 classes to classify the land use. In my result, cloud and the snow are categorized in the same class. How do I ...
3
votes
3answers
1k views

Problem with NDVI image value

I'm really happy to find this website. It is very helpful for the learners of Arcgis. Now I wanna ask a question. When i open NDVI image in ENVI, its value is still within the range (-1 to 1). But ...