[poppler] Problem with pdfimages

[Adrian Johnson]

Jean-Claude REPETTO wrote:
> Hello,
> 
> I am trying to extract an image from a PDF file, with pdfimages 0.10.2. 
> But pdfimages does not create any image, and reports no problem.
> So I am wondering what is wrong :
> - either the PDF contain no image (unlikely, because the document 
> contains only a scan of a geographic map)
> - either pdfimages is unable to read the image.
> 
> A few samples of these files can be downloaded at :
> <http://www.megaupload.com/?d=NSZXCZL9>
> 
> Can somebody have a look at these files and explain why pdfimages is not 
> able to extract the images ?
> 
> Thanks,
> Jean-Claude

The PDF files do not contain any images (except for the thumbnail 
images). The scanned image has been converted a vector format by drawing 
lots of closely spaced parallel lines. You can see this if you zoom in 
on the page. I assume this is for printing on a pen plotter.

You can create an image from each PDF page with pdftoppm. After 
converting to PNG this results in a much smaller and faster to render 
image but it does lose the shading effects that were created by the 
hatching.