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Anonymous
2010-05-11
2015-04-09
  • Anonymous

    Anonymous - 2010-05-11

    Hello,
    Can I change the resolution (DPI) of the generated pdf?
    I insert images to the document, and I want to print it on an A3 page with 300 dpi resolution.

    Thank you!

    Zoltan

     
  • Andrea M.F.

    Andrea M.F. - 2015-04-09

    same problem wheren i can find the document dpi ?

     
  • Stefano Chizzolini

    PDF documents have no intrinsic resolution (see my answer to a related question on stackoverflow for further details); their extrinsic resolution can only be reckoned ex-post depending on the device they are rendered through.

    The resolution of embedded sampled images is related to the coordinate system of the page where they are shown: if they are drawn in default user space units (that is typographic points, 1/72 inch), then you can calculate their point size given an internal resolution (samples / dpi * 72) or you can calculate their internal resolution given their point size (samples / pt * 72), for example:

    native image size: 1280x720 pixels
    
    1) calculate shown image size (points) given 300 dpi:
      internal resolution: 300 dpi
      shown image size:  307.2x172.8 points
    2) calculate internal resolution (dpi) given shown image size:
      shown image size:  460.8x259.2 points
      internal resolution: 200 dpi
    
     

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