Hi, If you are using gdal translate with -a_srs "EPSG:4326", you are simply overwriting the CRS in the file. That is likely messing thing up as the file is not actually reprojected. Nicolas
> Le 18 juin 2018 à 03:40, Donald Harter <harte...@att.net> a écrit : > > I started out trying to merge some geotiff topo maps of a state. I kept > getting results that were all black. It seems that style was palletee > unique values and that merge could not handle that. So I converted them > to multiband color using gdal_translate. Some of the merged topos were > not lining up next to each other as they should. It seems that they > were on the edge of a UTM region, each one in a different one. So I > decided to convert them to WGS84 latitude and longitude. I can > partially do that but when I display the files the coordinates seem to > be in utm instead of latitude and longitude. > Here is info on one such file: > > Original > out2 > Name > out2 > Source > /tmp/out2.tif > Provider > gdal > CRS > EPSG:4326 - WGS 84 - Geographic > Extent > 212740.2107839999953285,3630863.9934609998017550 : > 413984.4187070000916719,3772545.1990390000864863 > Unit > degrees > Width > 7923 > Height > 5578 > Data type > Byte - Eight bit unsigned integer > GDAL Driver Description > GTiff > GDAL Driver Metadata > GeoTIFF > Dataset Description > /tmp/out2.tif > Compression > > Band 1 > STATISTICS_MAXIMUM=255 > STATISTICS_MEAN=238.21578824081 > STATISTICS_MINIMUM=131 > STATISTICS_STDDEV=37.09178797644 > More information > AREA_OR_POINT=Area > TIFFTAG_DATETIME=1996:10:29 16:21:10 > TIFFTAG_IMAGEDESCRIPTION=USGS GeoTIFF DRG 1:250000 Quad of Tularosa. > Product:487866 > TIFFTAG_RESOLUTIONUNIT=2 (pixels/inch) > TIFFTAG_SOFTWARE=USGS CD Archiver program tif2usgsdrg v.1.0 > TIFFTAG_XRESOLUTION=250 > TIFFTAG_YRESOLUTION=250 > Dimensions > X: 7923 Y: 5578 Bands: 1 > Origin > 212740,3.77255e+6 > Pixel Size > 25.4,-25.4 > Its coordinates are EPSG:4326, but they display as UTM and not latitude > and longitude. It is as if the pixel data coordinates were not > converted but everthing else one. I have tried gdaltransform and > gdal_translate. > So how do I do this? Maybe I am forgetting a parameter. > Here is what I ran on the command line after the gui did not work: > > gdal_translate -a_nodata 0.0 -ot Byte -a_srs "EPSG:4326" -expand rgba > -of GTiff /srv/data/nm_topo/scale_250k/c33106a1.tif /tmp/out2.tif > > gdalwarp -ot Byte -s_srs "EPSG:4267" -t_srs "EPSG:4326" -of GTiff > /srv/data/nm_topo/scale_250k/c33106a1.tif /tmp/out2.tif > > I am using the latest version of qgis. If I try to use -expand in the > processing gui for translate it says that it is an invalid parameter. > It works on the command line though. > > _______________________________________________ > Qgis-user mailing list > Qgis-user@lists.osgeo.org > List info: https://lists.osgeo.org/mailman/listinfo/qgis-user > Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user _______________________________________________ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
