[gdal-dev] Wrong metadata or gdalinfo weakness (on Landsat scene over Madagascar)?
Kurtis Nelson
knelson at usgs.gov
Mon Aug 5 11:26:53 PDT 2013
Even is correct, all Landsat data from USGS (with very few exceptions)
are projected to UTM North zones, including southern hemisphere scenes.
The only difference between North and South UTM zones is a false
northing added to ensure positive y coordinates of southern scenes,
which is why the y coordinates in your data are negative.
PROJCS["WGS 84 / UTM zone 38N",
GEOGCS["WGS 84",
DATUM["WGS_1984",
SPHEROID["WGS 84",6378137,298.257223563,
AUTHORITY["EPSG","7030"]],
AUTHORITY["EPSG","6326"]],
PRIMEM["Greenwich",0,
AUTHORITY["EPSG","8901"]],
UNIT["degree",0.01745329251994328,
AUTHORITY["EPSG","9122"]],
AUTHORITY["EPSG","4326"]],
UNIT["metre",1,
AUTHORITY["EPSG","9001"]],
PROJECTION["Transverse_Mercator"],
PARAMETER["latitude_of_origin",0],
PARAMETER["central_meridian",45],
PARAMETER["scale_factor",0.9996],
PARAMETER["false_easting",500000],
_*PARAMETER["false_northing",0],*_
AUTHORITY["EPSG","32638"],
AXIS["Easting",EAST],
AXIS["Northing",NORTH]]
PROJCS["WGS 84 / UTM zone 38S",
GEOGCS["WGS 84",
DATUM["WGS_1984",
SPHEROID["WGS 84",6378137,298.257223563,
AUTHORITY["EPSG","7030"]],
AUTHORITY["EPSG","6326"]],
PRIMEM["Greenwich",0,
AUTHORITY["EPSG","8901"]],
UNIT["degree",0.01745329251994328,
AUTHORITY["EPSG","9122"]],
AUTHORITY["EPSG","4326"]],
UNIT["metre",1,
AUTHORITY["EPSG","9001"]],
PROJECTION["Transverse_Mercator"],
PARAMETER["latitude_of_origin",0],
PARAMETER["central_meridian",45],
PARAMETER["scale_factor",0.9996],
PARAMETER["false_easting",500000],
_*PARAMETER["false_northing",10000000],*_
AUTHORITY["EPSG","32738"],
AXIS["Easting",EAST],
AXIS["Northing",NORTH]]
__________________________________________________
Kurtis Nelson
Physical Scientist - Wildland Fire Science Team
United States Geological Survey (USGS)
Earth Resources Observation & Science (EROS) Center
knelson at usgs.gov
On 8/5/2013 12:38 PM, Even Rouault wrote:
> Selon Nikos Alexandris <nik at nikosalexandris.net>:
>
> GDAL is doing its job great on this case. The data is just oddly georeferenced,
> but the end result is OK if you look at the corner coordinates in longitude,
> latitude. The projection is UTM north, but with with negative y values, which
> means it is on the southern hemisphere. For a GEOTIFF GDAL will not look at the
> text files that might be or not be along the .TIF files. It will only look at
> the geotiff tags.
>
>
>> For the Landsat scene over Madagascar LE71610762013070PFS00, gdalinfo reports
>> UTM Zone 38N (EPSG:32638, <http://spatialreference.org/ref/epsg/32638/>).
>> This
>> is wrong. It should be UTM Zone 38 _S_ (EPSG:32738,
>> <http://spatialreference.org/ref/epsg/32738/>).
>>
>> Is it the metadata's fault or is gdalinfo wrongly guessing? Any help?
>>
>>
>> The scene contains in its (old) metadata file (that is the
>> LE71610762013070PFS00_MTLold.txt file):
>>
>> ,--%<---
>> GROUP = PROJECTION_PARAMETERS
>> REFERENCE_DATUM = "WGS84"
>> REFERENCE_ELLIPSOID = "WGS84"
>> GRID_CELL_SIZE_PAN = 15.000
>> GRID_CELL_SIZE_THM = 30.000
>> GRID_CELL_SIZE_REF = 30.000
>> ORIENTATION = "NUP"
>> RESAMPLING_OPTION = "CC"
>> SCAN_GAP_INTERPOLATION = 2
>> MAP_PROJECTION = "UTM"
>> END_GROUP = PROJECTION_PARAMETERS
>> GROUP = UTM_PARAMETERS
>> ZONE_NUMBER = 38
>> END_GROUP = UTM_PARAMETERS
>> `--->%--
>>
>>
>> The newer version of the metadata file reports:
>>
>> ,--%<---
>> GROUP = PROJECTION_PARAMETERS
>> MAP_PROJECTION = "UTM"
>> DATUM = "WGS84"
>> ELLIPSOID = "WGS84"
>> UTM_ZONE = 38
>> GRID_CELL_SIZE_PANCHROMATIC = 15.00
>> GRID_CELL_SIZE_REFLECTIVE = 30.00
>> GRID_CELL_SIZE_THERMAL = 30.00
>> ORIENTATION = "NORTH_UP"
>> RESAMPLING_OPTION = "CUBIC_CONVOLUTION"
>> SCAN_GAP_INTERPOLATION = 2.0
>> END_GROUP = PROJECTION_PARAMETERS
>> `--->%--
>>
>>
>> No sign of Northern or Southern hemisphere reference. Reporting on the scene
>> by using gdalinfo:
>>
>> ,--%<---
>> gdalinfo -nomd LE71610762013070PFS00_B1.TIF -proj4
>>
>> Driver: GTiff/GeoTIFF
>> Files: LE71610762013070PFS00_B1.TIF
>> Size is 8041, 6961
>> Coordinate System is:
>> PROJCS["WGS 84 / UTM zone 38N",
>> 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",45],
>> PARAMETER["scale_factor",0.9996],
>> PARAMETER["false_easting",500000],
>> PARAMETER["false_northing",0],
>> UNIT["metre",1,
>> AUTHORITY["EPSG","9001"]],
>> AUTHORITY["EPSG","32638"]]
>> PROJ.4 string is:
>> '+proj=utm +zone=38 +datum=WGS84 +units=m +no_defs'
>> Origin = (185385.000000000000000,-2452185.000000000000000)
>> Pixel Size = (30.000000000000000,-30.000000000000000)
>> Corner Coordinates:
>> Upper Left ( 185385.000,-2452185.000) ( 41d56'59.71"E, 22d 8'46.86"S)
>> Lower Left ( 185385.000,-2661015.000) ( 41d54'25.45"E, 24d 1'48.22"S)
>> Upper Right ( 426615.000,-2452185.000) ( 44d17'17.50"E, 22d10'24.01"S)
>> Lower Right ( 426615.000,-2661015.000) ( 44d16'41.43"E, 24d 3'34.61"S)
>> Center ( 306000.000,-2556600.000) ( 43d 6'20.60"E, 23d 6'24.43"S)
>> Band 1 Block=8041x1 Type=Byte, ColorInterp=Gray
>> `--->%--
>>
>> This is obviously wrong. It should be UTM Zone 38 _S_ (not _N_). That is EPSG
>> 32738 <http://spatialreference.org/ref/epsg/32738/> (and not 32638
>> <http://spatialreference.org/ref/epsg/32638/>).
>>
>> Thanks, Nikos
>> _______________________________________________
>> gdal-dev mailing list
>> gdal-dev at lists.osgeo.org
>> http://lists.osgeo.org/mailman/listinfo/gdal-dev
>>
>
> _______________________________________________
> gdal-dev mailing list
> gdal-dev at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/gdal-dev
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/gdal-dev/attachments/20130805/de90b1e2/attachment-0001.html>
More information about the gdal-dev
mailing list