Peter Willis <pwillis <at> aslenv.com> writes: > > Hello, > > Sorry about the title but it's a bit of a bear finding answers if the > headers don't show the actual topic. > But I digress. > > My Issue: > I have an input image that covers coordinates 0,0 to 450,350 UTM zone 13 > North and the pixel size is 1 meter. > > I want to mosaic pixels 0,0 to 25,25 into a coverage of UTM coordinates > -25,-25 : 25, 25 at the output in 1 meter pixels. > This should show a 25x25 square portion of the image in one corner of the > 50x50 output image. > > 'gdal_translate' will not do this because -25,-25 are outside the bounds > of the original image. > > I have tried the following with gdalwarp: > > gdalwarp -overwrite -te -25 -25 25 25 -tr 1 1 ./input.tif ./output.tif > > This does not work. I get the following error: > > ERROR 1: Unable to compute a transformation between pixel/line > and georeferenced coordinates for ./input.tif. > There is no affine transformation and no GCPs. > > There is geography applied to the input file. > > What am I doing wrong ?
Hi, This is funny. GDAL seems not to believe in images with origo at 0,0. I tested with some dummy png file gdal_translate -of gtiff -co tfw=yes -co profile=baseline test.png test.png test.tif Input file size is 588, 321 0...10...20...30...40...50...60...70...80...90...100 - done. It does not create a tfw file. Now this fails gdalwarp test.tif test2.tif ERROR 1: Unable to compute a transformation between pixel/line and georeferenced coordinates for test.tif. There is no affine transformation and no GCPs. I made tfw file test.tfw by hand as 1 0 0 -1 0 0 and then this is successful gdalwarp test.tif test2.tif Creating output file that is 588P x 321L. Processing input file test.tif. 0...10...20...30...40...50...60...70...80...90...100 - done. and also what you want to do gdalwarp -te -1000 -1000 1000 1000 test.tif testi3.tif Creating output file that is 2000P x 2000L. Processing input file test.tif. 0...10...20...30...40...50...60...70...80...90...100 - done. So I feel there is a bug if corner coordinates are 0,0. Please verify with a handwritten tfw file and images with origo at, let's say, 1,1. -Jukka Rahkonen- > Thanks for any help. > > Peter > _______________________________________________ gdal-dev mailing list gdal-dev@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/gdal-dev