I am tying to export an NDVI product to ENVI format but it is telling me that this is not possible and I should consider resampling first. Is there an easier way to just export the NDVI (ortho)? When I try to resample I get an error that says
An internal error occurred during the target product processing. Type: ConcurrentModificationExcception Message:null.
What kind of NDVI product are you using?
Have you used SNAP to compute it? If so, it should be already resampled.
Can you see some more details of the error message?
Hello,
Yes I did use SNAP to compute it. Sorry, I am new to Sentinel 2 and I have found that the tutorials offered do not provide me with the information I need. I did somehow figure out how to get the NDVI image exported however, I needed to export the entire image along with it. The NDVI band attaches to the bottom of the bands list for the initial image. Since I sort of figured out this issue I do not need help with it any more but possibly you can help me with another issue I am having?
I downloaded my images from the Copernicus site. I am able to import them into SNAP and work with them in SNAP but when I try to export the image and work with it in ENVI the reflectance values are not correct and the NDVI product I calculate using ENVI is drastically different (and incorrect) from the product created in SNAP. Are you able to explain to me why this is happening and possibly how to fix it so that I can work with the Sentinel 2 image in ENVI or Arcgis as well?
Thank you.
Exported are only the raw values. you need to apply the so called QUANTIFICATION_VALUE. It is in the metadata. The value is 10000. If you divide the values in ENVI by 10000 you should have the same values.
Thank you so much for your help.
Addy
Hi. When should we divide the values to 10000? Is it before exporting from SNAP or after importing to ENVI? Thank you
Actually it is not important when to do it. The result will be the same. But I think it is more practical if you divide the values in ENVI.
Before the export there are also other things to consider.
Hi Again. May I what are those things to consider?
Hi Sir Marco, Why is it that upon dividing the band with the quantification value of 10000 (Say, B2/10000), the wavelength value in ENVI Classic disappears?
I have no idea. I don’t use ENVI.