I am making a raster function using some band arithmetic and then applying a stretch the max is 162 and the min is -190, the mean is 0.18 and the std dev is 1.87.
I want to stretch those values between 0 and 255 to do more functions on this band. The problem is when I do a stretch with 2 std dev all values go to 127.5 everywhere. There is a large area in the centre of the image that pixels are all zero... It looks like the lack of statistics on the band calculation is preventing the stretch from being applies.