S3A and GPT

[marpet]

Already answered here:

Gpt: geographic conversion

Hi Monica, first, you should use SNAP and not gpt as name for the application. gpt is just one command line tool provided by SNAP. However, there are different ways from lat/lon coordinates to x/y coordinates. It depends on which data you are using. Sometimes there is with each pixel x/y a lat/lon coordinate given, sometimes there is only a sparse tie-point grid and in between the tie-points we need to interpolate the lat/lon coordinates. And then are cases were an affine transform is availab…