What is the exact problem that you are facing while extracting NDVI values from Landsat? If you specify your question with the exact error message, the RG community will be able to help you better. Are you using ERDAS Imagine Model Maker to create an NDVI Image? I have created an NDVI model in ERDAS Imagine, I can share it with you if you need. But before that it would be useful to know the error message associated with your NDVI extraction.

Hi Waheed,

Can you specify the issue or error you are getting in ERDAS while performing the NDVI. Which sensor data of Landsat you are using? and which version of ERDAS you are using etc.

This will help us to suggest a solution for your problem.

Vijith

I hope this helps