I am trying to extract and georeference the orange polygons/lines from this PDF file of the city of São Paulo, in Brazil.

To do so, I am mostly trying to follow what was discussed in another question, but none of the proposed solutions are working for me.

I tried using Adobe Illustrator to extract those and export to a DXF archive, but the QGIS step is curbing my advances. I am working in EPSG 32723. My first attempt was to use the affine transformation, but the imported shapefile could not pass through: all polygons had invalid geometries.

The attempt to use JOSM also failed. I cannot process the output from downloading São Paulo's data.

Is there another path to extract those vector objects?

  • Why did you try JOSM? Is the data in OpenStreetMap?
    – Spacedman
    Jun 30, 2022 at 18:35
  • 2
    I've loaded the PDF into Inkscape which lets me inspect the vector data under the orange areas, and its a real mess. Each orange polygon can be made of several parts, often overlapping, drawn in a very thick line, and sometimes not joining up as a polygon loop. I think it would be very difficult to extract useful vector data from this.
    – Spacedman
    Jun 30, 2022 at 18:46
  • @Spacedman Thank you. I am unsure about how to use JOSM for this particular task. An alternative file from the same set is prefeitura.sp.gov.br/cidade/secretarias/upload/urbanismo/…
    – catatau
    Jun 30, 2022 at 20:08
  • 2
    An alternative I am considering is to extract the orange polygons using Illustrator, forcing a conversion to raster, georreferencing, and then rebuilding the vectors.
    – catatau
    Jun 30, 2022 at 20:14
  • Using QGIS 3.26, I could load your pdf as raster layer in the georeferencer, but not as a vector layer.
    – Babel
    Jun 30, 2022 at 20:35


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