Printing Posters on GWDG Printers
=================================

Via one of GWDG's Linux Dialogservers
-------------------------------------

I was previously able to simple add the printer and type in my password when I wanted
to print, but this does not work anymore for me.
I wrote the GWDG Support and they gave me one way that worked:

#. Export your poster as an JPEG file. If you use Inkscape like me, you probably
   need to export it as PNG first and convert it to JPEG with imagemagick.
   When you export it to PNG, do not simply use :code:`save as`, rather use
   :code:`export as png`! There you can choose the size and everyting,
   make sure you use some physical length in mm, cm or inches, not pixels!
   You can convert with imagemagick in the command line:

   .. code:: bash

      $ convert poster.png poster.jpg

#. Check print parameters for your JPEG, again with imagemagick:

   .. code:: bash

      $ identify -verbose poster.jpg
   
   Important are the entries for :code:`Print size, Resolution`, and :code:`Units`.
   They have to be some physical units, that you can match to A0 or whatever size you
   want. If :code:`Units: PixelsPerInch`, the :code:`Print size` refers to Inches,
   If :code:`Units: PixelsPerCm` or something, the :code:`Print size` is in cm, etc.
   The :code:`Resolution` tells you the dpi or dots per cm or whatever your unit is.

   * example:

     .. code::

	$ identify -verbose DQ_A3_400ppi_sRGB_dt.jpg
	Image: DQ_A3_400ppi_sRGB_dt.jpg
	  Format: JPEG (Joint Photographic Experts Group JFIF format)
	  Mime type: image/jpeg
	  Class: DirectClass
	  Geometry: 6614x4677+0+0
	  Resolution: 400x400
	  Print size: 16.535x11.6925
	  Units: PixelsPerInch
	  ...

   * example:

     .. code::
	
	$ identify -verbose poster.jpg 
	Image: poster.jpg
	  Format: JPEG (Joint Photographic Experts Group JFIF format)
	  Mime type: image/jpeg
	  Class: DirectClass
	  Geometry: 9933x14043+0+0
	  Resolution: 118x118
	  Print size: 84.178x119.008
	  Units: PixelsPerCentimeter
	  ...

#. Copy file to an GWDG dialog server, e.g. :code:`gwdu60.gwdg.de`.
   You need an GWDG account for that! You can copy via scp or rsync. E.g.,
   I use:

   .. code:: bash

      $ rsync -uvt poster.jpg ikuhlem@gwdu60.gwdg.de:

   And then login to the server:

   .. code:: bash

      $ ssh ikuhlem@gwdu60.gwdg.de

#. Print from dialog server via command line. E.g. to print on the poster
   printer :code:`pcipls` in the physics library:

   .. code:: bash

      $ lpr -Ppcipls poster.jpg

Done!