Rodolfo, I don't remember how to choose the matrix to be inverted here. However you can read about GDAL's affine transformation coefficients in the documentation for GDALDataset::GetGeoTransform() [1]. You can also find relevant info at the GDAL Data Model page [2].
[1]: http://www.gdal.org/classGDALDataset.html#f9593cc241e7d140f5f3c4798a43a668 [2]: http://www.gdal.org/gdal_datamodel.html On Wed, Jul 6, 2011 at 12:03 AM, Rodolfo Bonnin < rodolfobon...@suremptec.com.ar> wrote: > Hello All, > > I'm working on a new PRISM driver, and it can now read the rasterbands from > all products. Now I'm working on reading the georeferencing data, and trying > to set the affine matrix coefficients. The format specification* says in > page 53 for one of the map projection fields: > > > Field No 58 > > Coefficient of F4 function (a, b, c, d, e, f) > > x' a b x e > = + > y' c d y f > > (x,y) : Map coordinate > (x',y') : Corrected Image address > > Remarks: > > Map projection origin = (0,0). > In case of UTM, map coordinate at an > intersection of the equator and UTM > zone refelence (sic) circles of longitude = (0,0) > > _____ > > * http://www.eorc.jaxa.jp/ALOS/en/doc/fdata/PRISM_L1_J_ENa.zip > > > Shall I assume the affine coefficients gdal requires, are those of the > inverse of the given matrix? Just to confirm. > Many thanks in advance. > > -- > Ing. Rodolfo Bonnin > SUR Emprendimientos Tecnológicos > > Perú 345 Piso 5to Oficina "B" (C1067AAG) > Ciudad de Buenos Aires, Argentina > Tel. +54 (11) 4342-2976/84 > rodolfobon...@suremptec.com.ar > www.suremptec.com > > _______________________________________________ > gdal-dev mailing list > gdal-dev@lists.osgeo.org > http://lists.osgeo.org/mailman/listinfo/gdal-dev > -- Best regards, Chaitanya kumar CH. /tʃaɪθənjə/ /kʊmɑr/ +91-9494447584 17.2416N 80.1426E
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