Hi there,

I was recently searching for a solution for not considering NoData values in ENVI calculations, but I was not able to find any solution in the user guides or even online. Basically, I have a big chunk of images organized in large time series, witch results in more than 300 bands (dates) images. My initial purpose is to calculate a few statistics based on this images, followed by vegetation indexes (per date). Obviously, NoData (witch in my MODIS images have the value of -9999) can not be considered when calculating anything for the time series, or the result would be modified.

The only efficient method I know for doing this on ENVI is to edit the header file of each image, indicating the ignore data value. But this method only works for the image display. When I calculate statistics or any kind of band combination, the NoData value (-9999) is considered. Based on this, I tried to indicate NoData values in some different GIS softwares, and the value was redefined. But, again, when the images are opened in ENVI, it considers the NoData real value for calculations. Masking the NoData seems not to be an efficient method for my data because NoData locations vary in each band, so I am searching for a simple way to ignore a single value.

Thank you very much for your attention, and I look forward for any possible solutions.