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## page was renamed from The texttopdf Filter
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A brief look at getting the most out of the texttopdf filter used with CUPS. A look at getting the most out of the texttopdf filter used with CUPS.
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On Debian 8.0.x (Jessie) and 7.0.x (Wheezy) font configuration is taken On Debian 8.0.x (Jessie) and 7.0.x (Wheezy) font selection is taken
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If pdf.utf-8.simple contains

{{{
  charset utf8
  0000 04FF ltor single monospace monospace:bold monospace:oblique monospace:bold:oblique
  0500 05FF rtol single monospace
}}}

you have version 1.0.68-2 or higher of cups-filters and are not using Wheezy or Jessie.

"monospace" is still a selector for fontconfig but the hard-coded request for !FreeMono is changed to the to the generic monospace alias. fontconfig returns the best suitable monospaced font that is available on the system. This might be !FreeMono or any other font. The actual preference of fonts can be configured per-system by means of fontconfig configuration files.
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  charset utf8
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Any of these three techniques can also be employed to get a particular font for printing with a system having cups-filters 1.0.68-2 or greater.
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technique involving Tea4cups. [LINK TO BE DONE] technique [[Tea4CUPS#Text to PDF with a Selected Font|involving Tea4cups]].
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Install fonts-freefont-ttf and print to file as described in [[The cupsfilter Utility|here.]] Install fonts-freefont-ttf and convert a text file to a PDF with [[http://manpages.debian.org/cgi-bin/man.cgi?query=cupsfilter|cupsfilter.]] The outputs below were obtained from a Jessie machine with a default install.
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Find the size of services.pdf and the fonts it uses. Find the size of services.pdf and run [[http://manpages.debian.org/cgi-bin/man.cgi?query=pdffonts|pdffonts]] to analyse the fonts it uses.
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The second file has the fonts embedded but not subset, In other words, The second file has the fonts embedded but not subset. In other words,
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out.pdf is searchable but not copyable. If you use pdffonts it can be seen there are no fonts embedded in it, so printing it would have to rely on whatever out.pdf is searchable and copyable. If you use pdffonts it can be seen there are no fonts embedded in it, so printing it would have to rely on whatever
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look elsewhere. The Tea4cups page [LINK TO COME] has a suggestion to make on this topic. look elsewhere. The Tea4cups page [[Tea4CUPS#Creating Searchable PDFs from Text Files|has a suggestion to make on this topic]].
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<<MailTo(smilingthax@googlemail.com,Tobias Hoffman)>> under the auspices of the [[https://wiki.linuxfoundation.org/en/OpenPrinting|OpenPrinting]] group. Significant work has been done in [[https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=662660| bug #662660]] and [[https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=663070|bug #663070]] by <<MailTo(fabian@debian.org,Fabian Greffrath)>> to integrate the use of fontconfig into the filter. <<MailTo(smilingthax SPAMFREE AT googlemail DOT com,Tobias Hoffman)>> under the auspices of the [[https://wiki.linuxfoundation.org/en/OpenPrinting|OpenPrinting]] group. Significant work has been done in [[https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=662660| bug #662660]] and [[https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=663070|bug #663070]] by <<MailTo(fabian SPAMFREE AT debian DOT org,Fabian Greffrath)>> to integrate the use of fontconfig into the filter.

Translation(s): none


A look at getting the most out of the texttopdf filter used with CUPS.

Font Selection and fontconfig

Printing a text file requires at least one suitable font to be available on the system. Supported font formats are TrueType (TTF), OpenType (OTF) and TrueType Collection (TTC). The font must be monospaced.

On Debian 8.0.x (Jessie) and 7.0.x (Wheezy) font selection is taken care of by fontconfig in conjunction with pdf.utf-8, which is found in /usr/share/cups/charsets and installed by the cups-filters package. By default pdf.utf-8 is symlinked to pdf.utf-8.simple, whose essential content is

  charset utf8
  0000 04FF ltor single FreeMono FreeMono:bold FreeMono:oblique FreeMono:bold:oblique
  0500 05FF rtol single FreeMono

Note that the font names are not file names but selectors which enable fontconfig to choose a monopaced font. The font used for printing will be FreeMono if fontconfig finds it on the system but otherwise it will conduct a search based on the generic font group which Freemono belongs to. FreeMono belongs to the monospace group of fonts so fontconfig will search for other fonts that are registered in this group and use the first match it finds.

If pdf.utf-8.simple contains

  charset utf8
  0000 04FF ltor single monospace monospace:bold monospace:oblique monospace:bold:oblique
  0500 05FF rtol single monospace

you have version 1.0.68-2 or higher of cups-filters and are not using Wheezy or Jessie.

"monospace" is still a selector for fontconfig but the hard-coded request for FreeMono is changed to the to the generic monospace alias. fontconfig returns the best suitable monospaced font that is available on the system. This might be FreeMono or any other font. The actual preference of fonts can be configured per-system by means of fontconfig configuration files.

Jessie and Wheezy Default Text Printing Font

Assuming a minimal Debian install (text mode, no desktop or window manager environment) the following will be the case:

On Jessie the cups-filters package pulls in fontconfig-config (via libfontconfig1) because it depends on it. In its turn fontconfig-config has the dependency

  ttf-dejavu-core | ttf-bitstream-vera | fonts-liberation | ttf-freefont

and so there is bound to be one monspaced TrueType font (from ttf-dejavu-core) installed. Because FreeMono is not there fontconfig will search and supply texttopdf with DejaVuSansMono. If you really wanted LiberationMono for your printed texts you could pre-empt the installation of ttf-dejavu-core by installing fonts-liberation before cups-filters.

On Wheezy the fontconfig-config font dependency is different:

  ttf-dejavu-core | ttf-bitstream-vera | ttf-freefont | gsfonts-x11

Also, while the Jessie cups-filters has no font dependency, the package for Wheezy has a Depends: line with

  ttf-freefont | fonts-liberation | ttf-dejavu

This means that ttf-freefont will be installed to satisfy both fontconfig-config and cups-filters and again texttopdf will have the use of a monospaced font because fontconfig will search and find FreeMono. To have DejaVuSansMono as the default font for printing the pre-emption would be done with ttf-dejavu.

Altering the System-wide Default Font for Printing

As pdf.utf-8.simple is written in Jessie and Wheezy fontconfig will always select FreeMono if this font is installed and only fall back to DejaVuSansMono or LiberationMono if it is not available. One of these must then be on the system to satisfy dependencies.

The previous section indicates one way of not using FreeMono but this is on a rather basic system. As the system develops FreeMono may become a requirement for other packages, such as vlc. So the question becomes: how can we have FreeMono but not use it for printing text files?

One way is to create the file pdf.utf-8.defaultfont and have pdf.utf-8 link to it.

  charset utf8
  0000 04FF ltor single defaultfont defaultfont:bold defaultfont:oblique defaultfont:bold:oblique

fontconfig will search first for defaultfont. Depending on the font, some adjustment may be needed to the typefaces used.

A second method is not to use fontconfig but specify exactly what font file to load in pdf.utf-8.defaultfont. For example, with the fonts-linuxlibertine package:

  • charset utf8 0000 04FF ltor single /usr/share/fonts/opentype/linux-libertine/LinLibertine_M.otf

A third approach is to follow the proposal here and alter pdf.utf-8.simple to

  charset utf8
  0000 04FF ltor single monospace monospace:bold monospace:oblique monospace:bold:oblique
  0500 05FF rtol single monospace

Then create /etc/fonts/local.conf with the contents

  <?xml version='1.0'?>
  <!DOCTYPE fontconfig SYSTEM 'fonts.dtd'>
  <fontconfig>
   <alias>
     <family>monospace</family>
     <prefer>
       <family>textttopdf_font</family>
     </prefer>
   </alias>
  </fontconfig>

to have a chosen font for printing.

Any of these three techniques can also be employed to get a particular font for printing with a system having cups-filters 1.0.68-2 or greater.

User Control of the Default Printing Font

If the print job is being sent to a local CUPS server it is possible to select the font used by putting the previous xml snippet in ~/.config/fontconfig/fonts.conf. This works whether or not root access to the server is available.

When the job is sent to a remote server the processing by texttopdf takes place there, so local font configuration in principle has no bearing on what font is used for printing. However, control of the font used can be gained with a technique involving Tea4cups.

The Case for FreeMono

The choice of a font for printing text files may very well be based on the look of the font. This is a reasonable criterion. However, there are other factors such as the range of glyphs in the font and, by implication, the language(s) used in the text.

GNU FreeMono has very good coverage of glyphs and caters for characters from many Unicode blocks. It may be compared with other monospaced fonts by producing and viewing a PDF of the UTF-8-demo.txt using ?cupsfilter.

A Difference Between TrueType and OpenType Fonts When Printing

Install fonts-freefont-ttf and convert a text file to a PDF with cupsfilter. The outputs below were obtained from a Jessie machine with a default install.

  /usr/sbin/cupsfilter /etc/services > services.pdf

Find the size of services.pdf and run pdffonts to analyse the fonts it uses.

brian@jessie:~$ ls -l services.pdf
-rw-r--r-- 1 brian brian 239047 Jun  9 16:35 services.pdf
brian@jessie:~$ pdffonts services.pdf
name             type          encoding    emb sub uni object ID
---------------  ------------  ----------  ---------------------
SHXZNP+FreeMono  CID TrueType  Identity-H  yes yes no      41  0

Remove fonts-freefont-ttf, replace it with fonts-freefont-otf and repeat.

brian@jessie:~$ ls -l services.pdf
-rw-r--r-- 1 brian brian 755004 Jun  9 16:23 services.pdf
brian@jessie:~$ pdffonts services.pdf
name                     type         encoding    emb sub uni object ID
-----------------------  -----------  ----------  ---------------------
FreeMonoBold-Identity-H  CID Type 0C  Identity-H  yes no  no      40  0
FreeMono-Identity-H      CID Type 0C  Identity-H  yes no  no      45  0

The second file has the fonts embedded but not subset. In other words, the complete font has been included in the file produced by texttopdf. This results in a much larger file to be sent to the printer and it might result in a longer printing time. This is not necessarily a problem but it is as well to be aware that using OTF is not yet equivalent to using TTF as the monospaced font.

Using texttpdf to Produce PDFs

The primary purpose of cups-filters is to process files (often in conjunction with CUPS) to produce an end product of toner or ink being put on a medium such as paper. However, it didn't take long for people to realise the CUPS+cupsfilters combination gave a way of capturing a PDF file without sending it to a printer. This opens up a way of archiving of files and scripting batch production of PDFs from them using something which is probably on the system already.

The command to use has been given earlier. Please look again at both pdffonts outputs in that section and note that uni is "no". This means there is no ToUnicode map in the PDF file and this in turn implies the text in the PDF is not searchable or capable of being copied. If this does not matter to you you have a decent method to produce a PDF from a text file.

If it does matter there is

   /usr/lib/cups/filter/texttopdf 1 2 3 4 5 input.txt > out.pdf

out.pdf is searchable and copyable. If you use pdffonts it can be seen there are no fonts embedded in it, so printing it would have to rely on whatever fonts the printer provides. It should be viewable on any machine because the font is courier.

For creating a searchable PDF with chosen embedded fonts you will have look elsewhere. The Tea4cups page has a suggestion to make on this topic.

Credits

The texttopdf filter is based on CUPS' texttops filter and written by Tobias Hoffman <smilingthax SPAMFREE AT googlemail DOT com> under the auspices of the OpenPrinting group. Significant work has been done in bug #662660 and bug #663070 by Fabian Greffrath <fabian SPAMFREE AT debian DOT org> to integrate the use of fontconfig into the filter.