[poppler] poppler get bounding box of whole content

[Albert Astals Cid]

El Dimecres, 29 de maig de 2013, a les 23:57:44, Mihai Niculescu va escriure:
> mail list included. Replay below.
> 
> On 05/29/2013 11:39 PM, Albert Astals Cid wrote:
> > El Dimecres, 29 de maig de 2013, a les 21:54:43, Mihai Niculescu va 
escriure:
> >> Hi,
> >> 
> >> I am trying to get the bounding box of all content in a page(text,
> >> images, tables, etc) in poppler, but I can’t figure this out.
> >> 
> >> For example, I want to dublicate the result given by ghostscript:
> >>               gs -sDEVICE=bbox golfer.ps
> >>    
> >>    prints out
> >>    
> >>               %%BoundingBox: 0 25 583 732
> >>               
> >>               %%HiResBoundingBox: 0.808497 25.009496 582.994503
> >>               731.809445
> >> 
> >> How can this be done with poppler?
> > 
> > Is that the "real" bounding box or one of the pdf boxes (crop, bleed,
> > etc)?
> > 
> > Cheers,
> > 
> >    Albert
> >> 
> >> Thanks,
> >> Mihai
> >> _______________________________________________
> >> poppler mailing list
> >> poppler at lists.freedesktop.org
> >> http://lists.freedesktop.org/mailman/listinfo/poppler
> > 
> > _______________________________________________
> > poppler mailing list
> > poppler at lists.freedesktop.org
> > http://lists.freedesktop.org/mailman/listinfo/poppler
> 
> Not the pdf boxes. I mean the union of all bounding boxes of all
> elements (text, images, tables, glyphs, etc) in pdf. Let me explain more.
> 
> I tried to loop over all QList<TextBox> but these do not include other
> glyphs in the pdf (greek sigma - for summation in latex) or maybe
> poppler does not see it as a text:
> 
>    QList<Poppler::TextBox*> wholetext = pdfPage->textList();
> 
>      //float minX, maxX, minY, maxY;
> 
>      QRectF unitedTextbbox, textbbox;
> 
>      for(int i=0; i<wholetext.size(); ++i){
> 
>          Poppler::TextBox* textBox = wholetext.at(i);
> 
>          textbbox = textBox->boundingBox();
> 
>          if(i==0){
> 
>              unitedTextbbox=textbbox;
> 
>          }else{
> 
>              unitedTextbbox=unitedTextbbox.united(textbbox);
> 
>          }
> 
>      }
> 
> 
> This works great when there is simple text in pdf, but when there are
> other symbols it does not.  I need something like the example above but
> to include all elements in the pdf. I'll go and use only poppler
> (without qt4 wrapper) if I can have this.

Can't think on how to get what you want easily to be honest.

As a quick solution you can render the page at a relatively low res and work 
the bbox from it, just check if the 4 corners are the same color and iterate 
on that.

Cheers,
  Albert

> 
> Cheers,
> Mihai
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> poppler at lists.freedesktop.org
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