Thank you for asking that question, Alex.
filters.odt (Writer version of filter.writer)
filters.ods (Calc version of filter.writer) (added 2015-11-18)
(filter.writer is hand-extracted from writer.xcd)
:~$ /opt/libreoffice5.0/program/soffice.bin --version
LibreOffice 5.0.0.5 437e4abdf9e72fd0a6e6f8697a0e659bc77f9b10
:~$ cat filter.writer | wc -l
69
Obtained from /opt/libreoffice5.0/share/registry/writer.xcd; Debian 6.0:
:~$ cat filter.writer | sort
"AbiWord Document" application/x-abiword Extensions:abw zabw
"Acta Mac v1-2 Document" Extensions:-
"Apple Pages 4" application/x-iwork-pages-sffpages Extensions:pages
"BeagleWorks/WordPerfect Works v1 Text Document" Extensions:-
"BroadBand eBook" application/x-sony-bbeb Extensions:lrf
"ClarisWorks/AppleWorks Text Document" application/clarisworks Extensions:cwk
"DOCMaker (v4) Document" Extensions:hqx zip
"eDOC (v2) Document" Extensions:hqx zip
"eReader eBook" application/vnd.palm Extensions:pdb
"FictionBook 2.0" application/x-fictionbook+xml Extensions:fb2 zip
"FullWrite Professional Document" Extensions:-
"GreatWorks Text Document" Extensions:-
"HanMac Word-J Document" Extensions:-
"HanMac Word-K Document" Extensions:-
"HTML Document" text/html Extensions:html htm
"LightWayText for Mac v4.5" Extensions:hqx zip
"Lotus WordPro Document" application/vnd.lotus-wordpro Extensions:lwp
"MacDoc v1 Document" Extensions:hqx zip
"MacWrite Document" application/macwriteii Extensions:mw mcw
"MacWriteII or MacWritePro Document" application/macwriteii Extensions:mw mcw
"Mariner Write Mac Classic v1.6 - v3.5" Extensions:mwd
"Microsoft Excel 4.0" application/vnd.ms-excel Extensions:xls xlw xlc xlm
"Microsoft Excel 5.0" application/vnd.ms-excel Extensions:xls xlc xlm xlw
"Microsoft Excel 95" application/vnd.ms-excel Extensions:xls xlc xlm xlw
"Microsoft WinWord 1/2/5" application/msword Extensions:doc
"Microsoft Word 2007-2013 XML" application/msword Extensions:docx docm
"Microsoft Word 2007-2013 XML Template" application/msword Extensions:dotx dotm
"Microsoft Word 6.0" application/msword Extensions:doc
"Microsoft Word 95" application/msword Extensions:doc
"Microsoft Word 95 Vorlage Template" application/msword Extensions:dot
"Microsoft Word 97-2003" application/msword Extensions:doc
"Microsoft Word 97-2003 Vorlage Template" application/msword Extensions:dot
"Microsoft Word for Mac (v1 - v5)" application/msword Extensions:doc
"Microsoft Works Document" application/vnd.ms-works Extensions:wps
"Microsoft Works for Mac Text Document (v1 - v4)" application/vnd.ms-works Extensions:wps
"MindWrite Document" Extensions:-
"MIZI Hangul WP 97" application/x-hwp Extensions:hwp
"More Mac v2-3 Document" Extensions:-
"Nisus Writer Mac Classic v3.4 - 6.5" Extensions:hqx zip
"Office Open XML Text Document" application/vnd.openxmlformats-officedocument.wordprocessingml.document Extensions:docx docm
"Office Open XML Text Template" application/vnd.openxmlformats-officedocument.wordprocessingml.template Extensions:dotx dotm
"OpenDocument Text Flat XML" application/vnd.oasis.opendocument.text-flat-xml Extensions:fodt odt xml
"OpenOffice.org 1.0 Master Document" application/vnd.sun.xml.writer.global Extensions:sxg
"PalmDoc eBook" application/x-aportisdoc Extensions:pdb
"PDF - Portable Document Format" application/pdf Extensions:pdf
"Plucker eBook" application/prs.plucker Extensions:pdb
"RagTime Mac v2-3 Document" Extensions:-
"Rich Text Format" application/rtf Extensions:rtf
"StarOffice XML (Writer 6.0) (OpenOffice.org 1.0 Text Document)" application/vnd.sun.xml.writer Extensions:sxw
"StarOffice XML (Writer 6.0) Template (OpenOffice.org 1.0 Text Template)" application/vnd.sun.xml.writer.template Extensions:stw
"StarOffice XML (Writer 6.0) Web Template (OpenOffice.org 1.0 HTML Template)" application/vnd.sun.xml.writer.web Extensions:stw
"StarOffice XML (Writer/Global 6.0)" application/vnd.sun.xml.writer.global Extensions:sxg
"T602 Document" application/x-t602 Extensions:602 txt
"TeachText/SimpleText v1 Document" Extensions:hqx zip
"TealDoc eBook" application/vnd.palm Extensions:pdb
"Tex-Edit v2 Document" Extensions:hqx zip
"Text - Choose Encoding (Master Document)" text/plain Extensions:csv tsv tab txt
"Text (Writer/Web 8 Template)" application/vnd.oasis.opendocument.text-web Extensions:oth
"WordPerfect Document" application/vnd.wordperfect Extensions:wpd
"WriteNow Document" Extensions:wn nx^d
"Writer 8 Document" application/vnd.oasis.opendocument.text Extensions:odt
"Writer 8 Document Template" application/vnd.oasis.opendocument.text-template Extensions:ott
"Writer 8 Master Document Template (Writer/Global 8 Template)" application/vnd.oasis.opendocument.text-master-template Extensions:otm
"Writer 8 Master Document (Writer/Global 8)" application/vnd.oasis.opendocument.text-master Extensions:odm
"Writer Layout Dump" Extensions:xml
"WriterPlus Document" Extensions:-
"Writer Web HTML Help content" Extensions:-
"zTXT eBook" application/vnd.palm Extensions:pdb
"Z-Write 1.3 Document" Extensions:hqx zip
My calculation is:
- Base: 1 filter
- Calc: 40 filters
- Graphics: 31 filters
- Impress: 21 filters
- Math: 5 filters
- Writer: 69 filters
Thus, 167 filters in total
If this helps then please show you like it with an uptick (∧)