The call to GetProjectionRef() returns an empty string. You can verify with gdalinfo - it shows the reference projection as `'. There are over 200 GCPs in my particular s1 file.

My code tries to do a "GetGeoTransform(double [6]);

and a

GDALInvGeoTransform(double[6], double[6]);

and then compute ground to image and image to ground with

GDALApplyGeoTransform().

The call to GetGeoTransform() returns 0s and 1s in the array, so that converting from image x = 10 y =200 yields a lat = 200 and lon =10.

How do I work this thing?