Projection Keywords not Propogated (ISIS 2/3, PDS)

[thare]

Currently the project parametars are getting propogated correctly from ISIS2,3 and PDS images. However not all projection keywords are coming through. This apparently use to work with an earlier versions (probably < 1.4.x). Is this potentially an easy fix or a potential large fix? See the label below to show a fully correct label and then a label that is slightly off. For example, the DATUM, SPHEROID, and PRIMEM keywords mapped in the code are getting set to unknown, uknown, and Greenwich respectively on output.

If this is a larger issue please let me know and we can figure out a long-term plan to help with this.

-Trent

past version of GDAL (more correct like Reference_Merdian):

#gdalinfo DEM_1m_ColumbiaHills.tif |more
Driver: GTiff/GeoTIFF
Files: DEM_1m_ColumbiaHills.tif
       DEM_1m_ColumbiaHills.tif.aux
Size is 6625, 10847
Coordinate System is:
PROJCS["Mars_2000_Sphere_Equatorial_Clon180",
    GEOGCS["GCS_Mars_2000_Sphere",
        DATUM["Mars_2000_Sphere",
            SPHEROID["Mars_2000_Sphere_IAU_IAG",3396190.0,0.0]],
        PRIMEM["Reference_Meridian",0.0],
        UNIT["Degree",0.0174532925199433]],
    PROJECTION["Equirectangular"],
    PARAMETER["False_Easting",0.0],
    PARAMETER["False_Northing",0.0],
    PARAMETER["Central_Meridian",180.0],
    PARAMETER["Standard_Parallel_1",0.0],
    UNIT["Meter",1.0]]
Origin = (-270182.209121626860000,-859042.088077538180000)
Pixel Size = (1.010722175708251,-1.010722175708249)

Current 1.5.x and 1.6dev label after conversion

#gdalinfo DEM_1m_VictoriaCrater.tif
Driver: GTiff/GeoTIFF
Files: DEM_1m_VictoriaCrater.tif
Size is 1278, 1694
Coordinate System is:
PROJCS["EQUIRECTANGULAR_CYLINDRICAL MARS",
    GEOGCS["GCS_MARS",
        DATUM["unknown",
            SPHEROID["unnamed",3396190,0]],
        PRIMEM["Greenwich",0],
        UNIT["degree",0.0174532925199433]],
    PROJECTION["Equirectangular"],
    PARAMETER["latitude_of_origin",0],
    PARAMETER["central_meridian",180],
    PARAMETER["false_easting",0],
    PARAMETER["false_northing",0],
    UNIT["metre",1,
        AUTHORITY["EPSG","9001"]]]
Origin = (10343034.842341581000000,-120699.132580911000000)
Pixel Size = (1.011855074660779,-1.011855074660779)

[warmerdam]

Trent,

I think that this ticket is complaining that the geotiff driver is no longer capturing the SRS names (the PCS and GCS names for instance). Is that right?

I have an ISIS3 dataset called mola_test.cub with a gdalinfo SRS report like:

PROJCS["TransverseMercator Mars",
    GEOGCS["GCS_Mars",
        DATUM["D_Mars",
            SPHEROID["Mars",3396190,169.8944472236118]],
        PRIMEM["Reference_Meridian",0],
        UNIT["degree",0.0174532925199433]],
    PROJECTION["Transverse_Mercator"],
    PARAMETER["latitude_of_origin",0],
    PARAMETER["central_meridian",110],
    PARAMETER["scale_factor",1],
    PARAMETER["false_easting",0],
    PARAMETER["false_northing",0]]

If I translate this to GeoTIFF the gdalinfo report indicates:

PROJCS["TransverseMercator Mars",
    GEOGCS["GCS_Mars",
        DATUM["unknown",
            SPHEROID["unnamed",3396190,169.894447223611]],
        PRIMEM["Greenwich",0],
        UNIT["degree",0.0174532925199433]],
    PROJECTION["Transverse_Mercator"],
    PARAMETER["latitude_of_origin",0],
    PARAMETER["central_meridian",110],
    PARAMETER["scale_factor",1],
    PARAMETER["false_easting",0],
    PARAMETER["false_northing",0],
    UNIT["metre",1,
        AUTHORITY["EPSG","9001"]]]

This seems to have retained the PROJCS and GEOGCS name, though the DATUM name was lost. The GeoTIFF format is not particularly good at preserving arbitrary names. Currently I think the geotiff writer maps PROJCS name to GTCitationGeoKey, and GEOGCS name to GeogCitationGeoKey. I'm not sure how I would preserve the DATUM name.

I have attempted the same translation and check with 1.5.3 and get similar results. I think you will need to be more specific about the problem.

[warmerdam]

Trent,

Can you supply more details for this ticket?

[thare]

I have been testing several image types isis2, isis3, and pds using GDAL 1.7dev and I am happy to say it appears to have been corrected. The projection keywords are maintain from the input into the output.

Even "Reference_Meridian" is propogated instead of "Greenwich" which is odd to see in a planetary dataset.

thanks, Trent