This may be a similar problem to what was mentioned here: #6721: Simplifing use of gdalwarp with cutline with non-georeferenced rasters
https://trac.osgeo.org/gdal/ticket/6721 (which has not been reacted to) There the gal was to use gdalwarp, together with a cutline, to cut out a portion of the non georeferenced raster (sample: image with folds which need to be removed). Here the idea was to emulate any meter base system (such as 3395 WGS 84 / World Mercator), creating a world file that always looks like this: 1.00000000000000 0.00000000000000 0.00000000000000 -1.00000000000000 0.00000000000000 0.00000000000000 Sample: small non georeferenced raster map from Wiki (1200x864): wget https://upload.wikimedia.org/wikipedia/commons/a/a0/Karte_berlin_akzisemauer.png -O 18550101.Karte_berlin_akzisemauer.wiki.png echo -e "1.00000000000000\n 0.00000000000000\n 0.00000000000000\n -1.00000000000000\n 0.00000000000000\n 0.00000000000000" > 18550101.Karte_berlin_akzisemauer.wiki.pgw gdal_translate -a_srs epsg:3395 18550101.Karte_berlin_akzisemauer.wiki.png 18550101.Karte_berlin_akzisemauer.wiki.ref_3395.tif gdalinfo 18550101.Karte_berlin_akzisemauer.wiki.ref_3395.tif Using '-te' create a cutline around the boundry shown on the map - remembering the 'y/height' is always minus (i.e top=0, bottom=height*-1) --> top=-50 ; bottom=-690 gdalwarp -s_srs epsg:3395 -t_srs epsg:3395 -te 220 -690 1160 -50 18550101.Karte_berlin_akzisemauer.wiki.ref_3395.tif 18550101.Karte_berlin_akzisemauer.cut.ref_3395.tif Without a world file you get with: gdalwarp -s_srs epsg:3395 -t_srs epsg:3395 -te 220 -690 1160 -50 18550101.Karte_berlin_akzisemauer.wiki.png 18550101.Karte_berlin_akzisemauer.cut.ref_png.tif ERROR 1: The transformation is already "north up" or a transformation between pixel/line and georeferenced coordinates cannot be computed for 18550101.Karte_berlin_akzisemauer.wiki.png. There is no affine transformation and no GCPs. Specify transformation option SRC_METHOD=NO_GEOTRANSFORM to bypass this check. (which is what you got) What the meaning of is: SRC_METHOD=NO_GEOTRANSFORM - no idea But with a world file the expected result comes out. Mark Johnson Berlin Germany
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