Here is the function that I use to convert from pixel x,y to lat,lon coordinate:
public static Coordinate imageToWorld(Dataset gds, int x, int y) { double[] adfGeoTransform = new double[6]; double[] p = new double[3]; gds.GetGeoTransform(adfGeoTransform); p[0] = adfGeoTransform[0] + adfGeoTransform[1] * x + adfGeoTransform[2] * y; p[1] = adfGeoTransform[3] + adfGeoTransform[4] * x + adfGeoTransform[5] * y; OSGeo.OSR.SpatialReference src = new OSGeo.OSR.SpatialReference(""); string s = gds.GetProjectionRef(); src.ImportFromWkt(ref s); //src.SetUTM(41, 1); OSGeo.OSR.SpatialReference wgs84 = new OSGeo.OSR.SpatialReference(""); wgs84.SetWellKnownGeogCS("WGS84"); OSGeo.OSR.CoordinateTransformation ct = new OSGeo.OSR.CoordinateTransformation(src, wgs84); ct.TransformPoint(p); return new Coordinate(p[0], p[1]); } but this function doesn't work for utm projection and gives incorrect longitude. for example for an image with the following WKT it gives 35.25,3.65 but it should be 35.29,61.17 @(x=0,y=0). if I uncomment line 12 it gives correct result only for this image.
PROJCS["WGS 84 / UTM zone 41N",GEOGCS["WGS 84",DATUM["WGS_1984",SPHEROID["WGS 84",6378137,298.257223563,AUTHORITY["EPSG","7030"]],AUTHORITY["EPSG","6326"]],PRIMEM["Greenwich",0],UNIT["degree",0.0174532925199433],AUTHORITY["EPSG","4326"]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",0],PARAMETER["central_meridian",0],PARAMETER["scale_factor",0.9996],PARAMETER["false_easting",0],PARAMETER["false_northing",0],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AUTHORITY["EPSG","32641"]]
