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Answering the comment about the world file, the world file doesn't explicitly say which projection is being used by the tiff, though it does encapsulate the information. So yes you can directly use the world file information, or you can run gdalinfo and it should provide the projection information for you, it's just a convenience. For more information on ...


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Here is another workflow, using ogr2ogr with GCP points: Extract the lines as svg (as above) load into inkscape and save as dxf Load into QGIS, with EPSG:31467 as CRS Read a couple of coordinates from significant edges of the surrounding city border Open OSM editor JOSM and download the relation 62591 of the city border Save that as GPX Load the border ...


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I stumbled upon your question while trying to do the same thing, here's how I did it: Software used: Inkscape QGIS 2.2 Affine Transformation plugin for QGIS (required some modification, as the number fields didn't allow for enough digits and/or precision) Extracting vector data from PDF It's what you have already done, basically just open the PDF in ...


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If the files have a world file (.tfw, .jpgw or .pngw), they don't need to be georeferenced. You only have to find out the proper coordinate system. Other choice: If you forget to enter a new file name for the output, the georeferencer might overwrite your last georeferncing result.


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Try converting your file to another/the same format (Raster/conversion/translate(convert format).There you can define a value for "no data", which you can set to a number different than 0. Hope it helps


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Second try, with EPSG:4326 and the following GCP: mapX,mapY,pixelX,pixelY,enable -74,20.1666666666700003,2053.94253295474391052,-2419.17835250553116566,1 -73,20,5225.22388495872564818,-2983.42925651106543228,1 -72,20,8392.67980710504343733,-2983.42925651106588703,1 -71,20,11579.26287853968642594,-2991.08011622639514826,1 ...


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My Spanish (Portuguese?) is rusty but I'm going to guess that it refers to the Greenwich Meridian, so your map is probably in some form of Lat/Long with 0 degrees at Greenwich so try EPSG:4326 first. To really determine the projection we'd need more details than just the prime meridian.


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The affine transformation makes no sense if you have lat/lon coordinates and a map in some kind of projection. This is how a map of your region looks in UTM 36N projection: and this is IsraeliTM: You can easily see that the meridians are not parallel, and the latitudes are large circles. Affine projection only works when the grid is orthogonal. Try ...


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Typical - after spending hours on this, I realised the answer a few minutes after posting the question to Stack Exchange. At least others can learn from my stupidity. I needed to add a 3rd control point, in order to allow the affine transformation to apply the correct adjustment:


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If you already have the projected shapefile defining the various islands then you may use the georeferencing toolbar to georeference your images. Once you have the images georeferenced you should create another shapefile (districts or something) from your island shapefile, and start an edit session and split/cut the various boundaries out referencing your ...


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Why can't you use a global data set? http://www.arcgis.com/home/item.html?id=3864c63872d84aec91933618e3815dd2 or http://www.gadm.org/


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Yep, under Raster > Georeferencer


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haha - got it - I opend the original image and re-saved it after converting from greyscale to 24bit RGB. Then I GeoRef the image. No corner infills visible.


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There are a few Reference systems shapefiles data that ESRI provide them when we install ESRI ArcGIS from DVD. You could find it in the "C:\Program Files (x86)\ArcGIS\Desktop10.x\Reference Systems" and in it has a shapefile that has UTM zones, but the coordinate system is in Geographic Coordinate System WGS 1984. So perhaps when you load them your UTM with ...


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I have edited this answer to reflect the new information in the question. I am leaving the old solutions for anyone who might find the question in future searches but actually have those issues. As dklassen pointed out they may have been created in 21S even though they don't 'belong' there, in which case bringing them in/defining them as what they should ...



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