[Qgis-user] trying to convert geotiff UTM toWGS84

Donald Harter harterc2 at att.net
Mon Jun 18 02:40:58 PDT 2018


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.




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