VobSub2SRT is a simple command line program to convert =.idx= / =.sub= subtitles into =.srt= text subtitles by using OCR. It is based on code from the [[http://www.mplayerhq.hu][MPlayer project]] - a really really great movie player. Some minor parts are copied from [[http://ffmpeg.org/][ffmpeg/avutil]] headers. [[http://code.google.com/p/tesseract-ocr/][Tesseract]] is used as OCR software.
vobsub2srt is released under the GPL3+ license. The MPlayer code included is GPL2+ licensed.
The quality of the OCR depends on the text in the subtitles. Currently the code does not use any preprocessing. But I'm currently looking into adding filters and scaling options to improve the OCR. You can correct mistakes in the =.srt= files with a text editor or a special subtitle editor.
sudo apt-get install libtiff5-dev libtesseract-dev tesseract-ocr-eng build-essential cmake pkg-config
You should also install the tesseract data for the languages you want to use! Note that the support for tesseract 2 is deprecated and will be removed in the future!
./configure make sudo make install
This should install the program vobsub2srt to =/usr/local/bin=. You can uninstall vobsub2srt with =sudo make uninstall=. ** Static binary I recommend using the dynamic binary! However if you really need a static binary you can add the flag =-DBUILD_STATIC=ON= to the =./configure= call. But be aware that building static binaries can be quite troublesome. You need the static library files for tesseract, libtill, libavutils, and for their dependencies as well. On Ubuntu 12.04 the static libraries are only included in the dev packages! You probably also need the Gold linker.
For Ubuntu 12.04 you need the following extra packages:
sudo apt-get install libleptonica-dev libpng12-dev libwebp-dev libgif-dev zlib1g-dev libjpeg-dev binutils-gold
If linking fails with undefined references then checking what other dependencies your version of leptonica has is a good starting point. You can do this by running =ldd /usr/lib/liblept.so= (or whatever the path to leptonica is on your system). Add those dependencies to =CMakeModules/FindTesseract.cmake=.
** Ubuntu PPA and .deb packages I have created a [[https://launchpad.net/~ruediger-c-plusplus/+archive/vobsub2srt][PPA (Personal Package Archive)]] to make installation on Ubuntu easy. Simply add the PPA to your apt-get sources and run an update and you can install the =vobsub2srt= package:
sudo add-apt-repository ppa:ruediger-c-plusplus/vobsub2srt sudo apt-get update sudo apt-get install vobsub2srt
** .deb (Debian/Ubuntu) You can build a .deb package (Debian/Ubuntu) with =make package=. The package is created in the =build= directory.
You can also create a source package and upload it to your own PPA by using the =UploadPPA.cmake=. But this is only recommended for people experienced with cmake and creating Debian packages.
** Homebrew Vobsub2srt contains a formula for [[http://mxcl.github.com/homebrew/][Homebrew]] (a package manager for OS X). It can be installed by using the following commands:
brew install --with-all-languages tesseract brew install --HEAD https://github.com/ruediger/VobSub2SRT/raw/master/packaging/vobsub2srt.rb
** Gentoo ebuild An [[http://en.wikipedia.org/wiki/Ebuild][ebuild]] for Gentoo Linux is also available. You can make it available to emerge with the following steps
sudo mkdir -p /usr/local/portage/media-video/vobsub2srt/ wget https://github.com/ruediger/VobSub2SRT/raw/master/packaging/vobsub2srt-9999.ebuild sudo mv vobsub2srt-9999.ebuild /usr/local/portage/media-video/vobsub2srt/ cd /usr/local/portage/media-video/vobsub2srt/ sudo ebuild vobsub2srt-999.ebuild digest
You should be able to install vobsub2srt with =emerge vobsub2srt= now. If you want to use a newer version (3+) of tesseract you have to use layman. See [[https://github.com/ruediger/VobSub2SRT/issues/13][#13]] for details. ** Arch AUR There also exist a [[https://wiki.archlinux.org/index.php/PKGBUILD][PKGBUILD]] file for Arch Linux in AUR: https://aur.archlinux.org/packages/vobsub2srt-git
vobsub2srt Filename
with =Filename= being the file name of the subtitle files WITHOUT the extension (=.idx= / =.sub=). vobsub2srt writes the subtitles to a file called =Filename.srt=.
If a subtitle file contains more than one language you can use the =--lang= parameter to set the correct language (Use =--langlist= to find out about the languages in the file). For some languages you might need to set the tesseract language yourself (e.g., chi_tra/chi_sim for traditional or simplified chinese characters). You can use =--tesseract-lang= to do this. In most cases this should however be autodetected.
If you want to dump the subtitles as images (e.g. to check for correct ocr) you can use the =--dump-images= flag.
Use =--help= or read the manpage to get more information about the options of vobsub2srt.
If you have problems with a specific subtitle file then please check if it works in mplayer first. If it does not then please report the bug to mplayer as well and link to the mplayer bug report.
For bug reports please run =vobsub2srt= with the =--verbose= option and copy and paste the full output to the bug report.