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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. Getting the most out of the texttopdf filter used with CUPS on jessie, stretch and buster
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<<Anchor(selection)>>
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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 configuration 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.

=== 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 [[https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=735223|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.
on the system. Supported font formats are [[WikiPedia:TrueType|TrueType]] (TTF), [[WikiPedia:OpenType|OpenType]] (OTF) and [[WikiPedia:TrueType#TrueType_Collection|TrueType Collection]] (TTC). The font should be [[WikiPedia:Monospaced_font|monospaced]].

Font selection is taken care of within the [[DebianPkg:fontconfig|fontconfig]] framework, documented in [[DebianMan:fonts-conf|fonts-conf]], in conjunction with ''pdf.utf-8'', which is found in ''/usr/share/cups/charsets'' and installed by the [[DebianPkg:cups-filters|cups-filters]] package. By default, ''pdf.utf-8'' is symlinked to ''pdf.utf-8.simple'', whose essential content on Debian 8.x (jessie) 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 that enable fontconfig to choose a monopaced font. The font used for printing will ''always'' be [[DebianPkg:fonts-freefont|FreeMono]] if fontconfig finds it on the system, but otherwise it will conduct a search based on the generic font group that 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.

On Debian 9.x (stretch) and Debian 10.x (buster) ''pdf.utf-8.simple'' [[DebianBug:788048|has been changed]] to contain

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

''monospace'' is still a selector for fontconfig but the hard-coded request for !FreeMono is changed to the generic monospace alias. fontconfig returns what it considers to be the best suitable monospaced font that is available on the system. This might be !FreeMono or [[DebianPkg:fonts-dejavu-core|DejaVuSansMono]] or any other monospaced font. A preference for a particular font can be configured on a [[#system|per-system]] basis by altering which file ''pdf.utf-8'' links to (jessie, stretch and buster) or by means of a fontconfig configuration file (stretch and buster only). A user with a font preference is [[#user|also catered for]].

<<Anchor(system)>>
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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 [[https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=788048|here]] and alter pdf.utf-8.simple to

{{{
  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.
The cups-filters package has [[DebianBug:735223|no dependency on a specific font package]] but it pulls in [[DebianPkg:fontconfig-config|fontconfig-config]] (via [[DebianPkg:libfontconfig1|libfontconfig1]]) because it depends on it. In its turn fontconfig-config has the dependency

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

All these four packages have a monospaced font. Consequently, there will always be one monospaced font on the system


 * '''jessie.'''
As ''pdf.utf-8.simple'' is written on jessie, fontconfig will always select [[DebianPkg:fonts-freefont-ttf|FreeMono]] if this font is installed. It will only fall back to one of [[DebianPkg:fonts-dejavu-core|DejaVuSansMono]] or [[DebianPkg:fonts-liberation|LiberationMono]] or [[DebianPkg:ttf-bitstream-vera|VeraMono]] if !FreeMono is not available. To specify exactly what font to use, the file ''pdf.utf-8.defaultfont'' can be created to replace ''pdf.utf-8.simple'' and linked to ''pdf.utf-8''. With the [[DebianPkg:fonts-linuxlibertine|fonts-linuxlibertine]] package it would be sufficient to have ''pdf.utf-8.defaultfont'' as

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

This bypasses fontconfig and also works on stretch and buster.

Substituting the stretch or buster ''pdf.utf-8.simple'' for the jessie version is also something to consider.

 * '''stretch and buster.'''
The preferred way of using a chosen ''textttopdf_font'' on stretch and buster would be to create ''/etc/fonts/local.conf'' with the contents

<<Anchor(snippet)>>
{{{
<?xml version='1.0'?>
<!DOCTYPE fontconfig SYSTEM 'fonts.dtd'>
<fontconfig>
 <alias>
   <family>monospace</family>
   <prefer>
     <family>textttopdf_font</family>
   </prefer>
 </alias>
</fontconfig>
}}}

<<Anchor(user)>>
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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. [LINK TO BE DONE]
Printing filters are always run as a non-privileged user, typically ''lp'', with no connection to the user's desktop. On jessie, stretch and buster a text file is first processed by texttopdf to produce a PDF that is then sent to the [[DissectingandDebuggingtheCUPSPrintingSystem#pdfcentric|pdftopdf]] filter. The PDF has the user-chosen font embedded in it.

 * '''jessie.'''
Create the directory ''$HOME/charsets'' and the file ''pdf.utf-8'' (examples below). Put ''pdf.utf-8'' into ''$HOME/charsets''. Convert the text file to a PDF with

{{{
CUPS_DATADIR=$HOME CHARSET=utf-8 /usr/lib/cups/filter/texttopdf 1 1 1 1 1 < text_file> > out.pdf
}}}

''$CUPS_DATADIR'' would normally be ''/usr/share/cups/'' but texttopdf will now look for the character set in a charsets directory in the home directory. Here are two example ''$HOME/charsets/pdf.utf-8'' files that will override the hard-coded !FreeMono font selection:

{{{
charset utf8
0000 04FF ltor single /usr/share/fonts/truetype/noto/NotoMono-Regular.ttf

charset utf8
0000 04FF ltor single LiberationMono LiberationMono:bold LiberationMono:oblique LiberationMono:bold:oblique
}}}

 * '''stretch and buster.'''
Use the xml snippet [[#snippet|above]] in ''$HOME/.config/fontconfig/fonts.conf''. The user's ''fonts.conf'' will take precedence over the system's ''/etc/fonts/local.conf'' because texttopdf is being run by an ordinary user. Produce a PDF with

{{{
CHARSET=utf-8 /usr/lib/cups/filter/texttopdf 1 1 1 1 1 < text_file> > out.pdf
}}}

The two-step production of a PDF and sending it to the printing system can be automated with [[Tea4CUPS#Text to PDF with a Selected Font|Tea4CUPS]]

<<Anchor(case)>>
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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.

[[http://www.gnu.org/software/freefont/|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
[[http://www.cl.cam.ac.uk/~mgk25/ucs/examples/|UTF-8-demo.txt]] using [[The cupsfilter Utility|cupsfilter.]]
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 [[WikiPedia:Glyphs|glyphs]] in the font and, by implication, the language(s) used in the text.

[[http://www.gnu.org/software/freefont/|GNU FreeMono]] has very good coverage of glyphs and caters for characters from many [[WikiPedia:Unicode_blocks|Unicode blocks]]. It can be compared with other monospaced fonts by [[#system|altering the system font]] and producing and viewing a PDF of
[[http://www.cl.cam.ac.uk/~mgk25/ucs/examples/|UTF-8-demo.txt]] using [[ThecupsfilterUtility|cupsfilter:]]

 * Produce a PDF with
{{{
/usr/sbin/cupsfilter UTF-8-demo.txt > out.pdf
}}}

 * Check the font used with
{{{
pdffonts out.pdf
}}}

 * View the PDF with
{{{
your_favourite_pdf_viewer out.pdf
}}}

<<Anchor(difference)>>
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Install fonts-freefont-ttf and print to file as described in [[The cupsfilter Utility|here.]]

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

Find the size of services.pdf and the fonts it uses.
Install [[DebianPkg:fonts-freefont-ttf|fonts-freefont-ttf]] and convert a text file to a PDF with [[DebianMan:cupsfilter|cupsfilter.]] The outputs below were obtained from a jessie machine with a default installation.

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

Find the size of services.pdf and run [[DebianMan:pdffonts|pdffonts]] to analyse the fonts it uses:
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Remove fonts-freefont-ttf, replace it with fonts-freefont-otf and
repeat.
Remove fonts-freefont-ttf, replace it with [[DebianPkg:fonts-freefont-otf|fonts-freefont-otf]] and repeat.
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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 [[https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=663192|not yet equivalent]] to using TTF as the monospaced font.
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 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 for the monospaced font.

<<Anchor(pdfs)>>
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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 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
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 [LINK TO COME] has a suggestion to make on this topic.
The primary purpose of cups-filters is to process files (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 text files and scripting batch production of PDFs from them using something that is probably on the system already.

The command to use has been [[#difference|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. Should this does not matter to you then you have a decent method to produce a PDF from a text file with

{{{
/usr/sbin/cupsfilter input.txt > out.pdf
}}}

Should a searchable PDF matter

{{{
/usr/lib/cups/filter/texttopdf 1 1 1 1 1 input.txt > out.pdf
}}}

can be resorted to; out.pdf is searchable and copyable. However, pdffonts shows there are no fonts embedded in the PDF, so printing it would have to rely on whatever fonts the printer provides. The PDF should be viewable on any machine because the font is courier.

Alternatively, the PDF produced by cupsfilter or texttopdf can be post-processed with [[DebianMan:pdftocairo|pdftocairo]] to obtain a searchable PDF with a chosen embedded font:

 * '''With the [[#system|system]] text font.'''
{{{
/usr/sbin/cupsfilter input.txt | pdftocairo -pdf - out.pdf
}}}

 * '''With a [[#user|user's]] text font on stretch and buster.'''

{{{
CHARSET=utf-8 /usr/lib/cups/filter/texttopdf 1 1 1 1 1 input.txt | pdftocairo -pdf - out.pdf
}}}

You might want to look at the [[Tea4CUPS|Tea4cups page]] for ideas on creating a searchable PDF with chosen embedded fonts as part of the printing system workflow.

=== Text Orientation ===

texttopdf handles a text file such as ''/etc/services'' by producing a [[pdftopdfandPageRotation#portrait|PDF portrait page]] with the text parallel to the short edge. If either ''landscape'' or ''orientation-requested=4'' is given as an option to texttopdf, the PDF is a [[pdftopdfandPageRotation#portrait|landscape page]] and the text is placed parallel to the long edge. The second PDF is [[pdftopdfandPageRotation#autorotate|processed by pdftopdf]] to print correctly.

{{{

lp -d <queue> /etc/services lp -d <queue> -o landscape /etc/services
     +------------+ +----------------------+
     |AAAAAAAAAAAA| |BBBBBBBBBBBBBBBBBBBBBB|
     | | | |
     | | | |
     | | +----------------------+
     | |
     | |
     +------------+
}}}
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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 Hoffmann)>> 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.

=== See Also ===
 * [[Printing|The Debian Printing Portal]]
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## If this page belongs to an existing Category, add it below.
## CategorySomething | CategoryAnother

CategoryPrinter

Translation(s): none


Getting the most out of the texttopdf filter used with CUPS on jessie, stretch and buster

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 should be monospaced.

Font selection is taken care of within the fontconfig framework, documented in fonts-conf, 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 on Debian 8.x (jessie) 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 that enable fontconfig to choose a monopaced font. The font used for printing will always be FreeMono if fontconfig finds it on the system, but otherwise it will conduct a search based on the generic font group that 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.

On Debian 9.x (stretch) and Debian 10.x (buster) pdf.utf-8.simple has been changed to contain

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

monospace is still a selector for fontconfig but the hard-coded request for FreeMono is changed to the generic monospace alias. fontconfig returns what it considers to be the best suitable monospaced font that is available on the system. This might be FreeMono or DejaVuSansMono or any other monospaced font. A preference for a particular font can be configured on a per-system basis by altering which file pdf.utf-8 links to (jessie, stretch and buster) or by means of a fontconfig configuration file (stretch and buster only). A user with a font preference is also catered for.

Altering the System-wide Default Font for Printing

The cups-filters package has no dependency on a specific font package but it pulls in fontconfig-config (via libfontconfig1) because it depends on it. In its turn fontconfig-config has the dependency

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

All these four packages have a monospaced font. Consequently, there will always be one monospaced font on the system

  • jessie.

As pdf.utf-8.simple is written on jessie, fontconfig will always select FreeMono if this font is installed. It will only fall back to one of DejaVuSansMono or LiberationMono or VeraMono if FreeMono is not available. To specify exactly what font to use, the file pdf.utf-8.defaultfont can be created to replace pdf.utf-8.simple and linked to pdf.utf-8. With the fonts-linuxlibertine package it would be sufficient to have pdf.utf-8.defaultfont as

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

This bypasses fontconfig and also works on stretch and buster.

Substituting the stretch or buster pdf.utf-8.simple for the jessie version is also something to consider.

  • stretch and buster.

The preferred way of using a chosen textttopdf_font on stretch and buster would be to 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>

User Control of the Default Printing Font

Printing filters are always run as a non-privileged user, typically lp, with no connection to the user's desktop. On jessie, stretch and buster a text file is first processed by texttopdf to produce a PDF that is then sent to the pdftopdf filter. The PDF has the user-chosen font embedded in it.

  • jessie.

Create the directory $HOME/charsets and the file pdf.utf-8 (examples below). Put pdf.utf-8 into $HOME/charsets. Convert the text file to a PDF with

CUPS_DATADIR=$HOME CHARSET=utf-8 /usr/lib/cups/filter/texttopdf 1 1 1 1 1 < text_file> > out.pdf

$CUPS_DATADIR would normally be /usr/share/cups/ but texttopdf will now look for the character set in a charsets directory in the home directory. Here are two example $HOME/charsets/pdf.utf-8 files that will override the hard-coded FreeMono font selection:

charset utf8
0000 04FF ltor single /usr/share/fonts/truetype/noto/NotoMono-Regular.ttf

charset utf8
0000 04FF ltor single LiberationMono LiberationMono:bold LiberationMono:oblique LiberationMono:bold:oblique
  • stretch and buster.

Use the xml snippet above in $HOME/.config/fontconfig/fonts.conf. The user's fonts.conf will take precedence over the system's /etc/fonts/local.conf because texttopdf is being run by an ordinary user. Produce a PDF with

CHARSET=utf-8 /usr/lib/cups/filter/texttopdf 1 1 1 1 1 < text_file> > out.pdf

The two-step production of a PDF and sending it to the printing system can be automated with 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 can be compared with other monospaced fonts by altering the system font and producing and viewing a PDF of UTF-8-demo.txt using cupsfilter:

  • Produce a PDF with

/usr/sbin/cupsfilter UTF-8-demo.txt > out.pdf
  • Check the font used with

pdffonts out.pdf
  • View the PDF with

your_favourite_pdf_viewer out.pdf

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 installation.

/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 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 for the monospaced font.

Using texttpdf to Produce PDFs

The primary purpose of cups-filters is to process files (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 text files and scripting batch production of PDFs from them using something that 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. Should this does not matter to you then you have a decent method to produce a PDF from a text file with

/usr/sbin/cupsfilter input.txt > out.pdf

Should a searchable PDF matter

/usr/lib/cups/filter/texttopdf 1 1 1 1 1 input.txt > out.pdf

can be resorted to; out.pdf is searchable and copyable. However, pdffonts shows there are no fonts embedded in the PDF, so printing it would have to rely on whatever fonts the printer provides. The PDF should be viewable on any machine because the font is courier.

Alternatively, the PDF produced by cupsfilter or texttopdf can be post-processed with pdftocairo to obtain a searchable PDF with a chosen embedded font:

/usr/sbin/cupsfilter input.txt | pdftocairo -pdf - out.pdf
  • With a user's text font on stretch and buster.

CHARSET=utf-8 /usr/lib/cups/filter/texttopdf 1 1 1 1 1 input.txt | pdftocairo -pdf - out.pdf

You might want to look at the Tea4cups page for ideas on creating a searchable PDF with chosen embedded fonts as part of the printing system workflow.

Text Orientation

texttopdf handles a text file such as /etc/services by producing a PDF portrait page with the text parallel to the short edge. If either landscape or orientation-requested=4 is given as an option to texttopdf, the PDF is a landscape page and the text is placed parallel to the long edge. The second PDF is processed by pdftopdf to print correctly.

lp -d <queue> /etc/services      lp -d <queue> -o landscape /etc/services
     +------------+                      +----------------------+
     |AAAAAAAAAAAA|                      |BBBBBBBBBBBBBBBBBBBBBB|
     |            |                      |                      |
     |            |                      |                      |
     |            |                      +----------------------+  
     |            |
     |            |
     +------------+ 

Credits

The texttopdf filter is based on CUPS' texttops filter and written by Tobias Hoffmann <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.

See Also


CategoryPrinter