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I have data as PDF file about the spatial categories of the German sea.

I sucessfully managed to import files about Windparks and military zones into QGIS by simply dragging them into the window and they matched with my other maps. My goal is to redraw the zones to get some vector files.

However when i tried the exact same thing with the PDF files of the protected sites ( Schutz und Eignungsgebiete) and other files, it only showed me empty layers.

I tried it with different CBS but i didnt seem to find the correct one even tho it says WSG 84.

When i import the files into an empty project they will show, however other files will then show empty.

Here's the dataset:

http://www.bsh.de/de/Meeresnutzung/Wirtschaft/CONTIS-Informationssystem/ContisKarten/NordseeSchutzUndEignungsgebiete.pdf

AndreJ
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K. Schwed
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1 Answers1

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The PDF contains raster and vector layers, but no CRS or extent information. So the data can not be shown at the right position.

gdalinfo Nordsee.pdf --mdd LAYERS reports these layers:

<Metadata domain="LAYERS">
  <MDI key="LAYER_00_NAME">Other_2</MDI>
  <MDI key="LAYER_01_NAME">Towns_Anno</MDI>
  <MDI key="LAYER_02_NAME">Grenzen</MDI>
  <MDI key="LAYER_03_NAME">Besondere_Eignungsgebiete</MDI>
  <MDI key="LAYER_04_NAME">Image</MDI>
  <MDI key="LAYER_05_NAME">Other</MDI>
</Metadata>

See How to have GDAL print layers of GeoPDF AND say which are raster vs vector on the export of PDF raster and vector layers.

Layers 00, 02, 03 and 05 are vector layers that can be saved with ogr2ogr into a spatialite database, the others seem to be rasters. You have to add the layers as Mercator projected, I took EPSG:3857.

Simply drag and drop to the legend returns just one layer with all data. If you want the individual raster layers, you have to use:

gdal_translate Nordsee.pdf Nordsee01.tif --config GDAL_PDF_LAYERS "Towns_Anno"
gdal_translate Nordsee.pdf Nordsee04.tif --config GDAL_PDF_LAYERS "Image"

The raster layers do not overlay the vector layers, because of the missing georeference (raster axis have a different orientation than usual CRS).

So you get this out of the PDF:

enter image description here

The only solution is to ask the data provider about the georeference. Maybe they don't want to publish the data georeferenced.

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AndreJ
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  • What about spatially adjusted the vector data (not sure if there are any good reference points in this data) like:http://gis.stackexchange.com/questions/33208/how-to-georeference-a-vector-layer-with-control-points – artwork21 Sep 01 '16 at 12:24
  • The PDF contains degree marks at the borders, but no values on the corners. You would have to approximate the degree intersections and do normal raster georeferencing on them. – AndreJ Sep 01 '16 at 13:16