< Projects | NepomukRevision as of 18:31, 10 September 2012 by Vhanda (talk | contribs)(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff) Nepomuk currently acts as the file indexer for the KDE platform, applications and workspaces. Even though we frequently tout that we are not just a file indexer, we need to index the files properly. Contents 1 File indexing solutions 1.1 Strigi 1.2 Roll our own? 2 File Formats 2.1 Images 2.2 Videos 2.3 Audio 2.4 Documents 2.4.1 Microsoft Formats 2.4.2 Open document formats 2.4.3 Ebook formats 2.4.4 Other 2.5 Archives 2.6 Emails 2.7 Text Files 2.8 ISO images 2.9 Executable files File indexing solutions Strigi The KDE software releases in version 4.9, currently use libstreamanalyzer to index the files. Current problems with strigi - Difficult to contribute to No documentation Un-maintained Does not reuse libraries Has its own huge parsers for archives, utf, etc. Roll our own? Maybe it would be better to roll our own file parsers which are just light wrappers over the existing libraries. File Formats We list down all the different file formats, and which all are supported by the different file indexing solutions. Images JPEG - Use exiv - strigi also uses exiv - currently broken PNG - Strigi rolls its own - detects the application name, color depth and interlace mode as well GIF - there isn't much metadata EXIF TIFF BMP SVG - Strigi stores them as plain text We just use exiv2 and cover almost everything. Plus the code would be super simple. Videos Strigi uses ffmpeg except for ID3, vorbis and OggS. It also has to seek through the file. Not sure what that is for. Overall, we could just use ffmpeg for everything. It's very fast and pretty much supports all the formats. Audio MP3 FLAC WAV Strigi rolls its own for id3 metadata. We should use taglib or ffmpeg. It seems to handle flac and wav files pretty well. Documents PDF - Strigi uses their own which is crap. We should use poppler. ODF - Strigi inbuilt. We should Microsoft Formats DOC - OLE 2 Compound Document and Office Open XML - Custom parser by Strigi. What can we use? <br\> XSL - http://qt-project.org/wiki/Handling_Microsoft_Excel_file_format <br\> spreadsheet formats <br\> Maybe we can use some libreoffice or calligra libraries? Open document formats ODF? Custom analyzer by Strigi. Ebook formats epub - Strigi reuses their ODF parser for epub mobi rtf lrf Checkout what Okular uses. Try using that. Other lyx tex cbz - Comic books Archives tar gzip whatever .. Strigi has its own analyzers for each archive which doesn't really add any metadata. It just adds the type nfo:Archive. We can do the same based on the mimetype. Emails mbox format - There was a bug report Text Files Text files Source Code ISO images Add the type based on the mimetype Executable files Use Mimetype Retrieved from "https://community.kde.org/index.php?title=Projects/Nepomuk/FileIndexing&oldid=23991" Content is available under Creative Commons License SA 4.0 unless otherwise noted.