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3. Scripts

A script is a file containing the text of the subtitles you want to display along with the exact times that each subtitle is to be displayed on the screen. Different subtitling programs use different file formats for their scripts. The subtitling program that we use, called transcode, supports a single script format, called PPML. Unfortunately, nobody outside of the Linux world uses PPML scripts, so we will first need to convert scripts to PPML format before we can use them. Don't worry about this too much, it will all be covered in the following sections.

There are basically three ways to obtain a script for a DVD:

3.1 Downloading timed scripts

Occasionally it is possible to find the scripts that you want on the internet. For example, scripts for many of the most popular anime titles are available at

Because of the great diversity of users on the internet, the various scripts available on the internet come in a wide variety of file formats. The best strategy here is to use mplayer to convert the script to SRT format, and then afterwards convert the SRT script to PPML format as described in this section.

Mplayer supports about a dozen different formats, which are listed here. You can convert any of these formats to SRT by using the -dumpsrtsub option in mplayer. For example,

mplayer -sub example.ssa -dumpsrtsub -dvd 1

The conversion process is not perfect because mplayer (and transcode for that matter) only supports one subtitle stream. Newer versions of mplayer make some attempt to simulate multiple subtitle streams within a single stream, but in most cases overlapping subtitles still require manual intervention to reconstruct. Also, mplayer does not support any formatting capabilities, so as a rule all formatting in the original script is lost as well.

3.2 Ripping subtitles off of the DVD

A lot of DVDs are starting to include subtitles on the disc itself. If your DVD comes with subtitles in the language you want, then you can rip those subtitles off of the disc and essentially get yourself a script for free. This procedure is useful even if the subtitles on the DVD are not in the same language as the language you want to subtitle in, since the timings on the disc will still be accurate even if the language is wrong.

The mplayer program comes with a subrip.c program in the TOOLS/ subdirectory, which is what we will use to rip the subtitles. You have to change a couple of lines in this program in order to get it to work:

  1. Change the #define GOCR_PROGRAM ... line to point to the actual installed location of the gocr program on your system.
  2. In the sprintf(cmd, GOCR_PROGRAM" ... line, get rid of all the -m options.

Then compile it according to the instructions at the top of the file.

You also need to have gocr installed.

Now you are ready to rip the subtitles off of your DVD:

rm frameno.avi
mencoder -dvd T -vobsubout subtitles -vobsuboutindex 0 -sid N -o frameno.avi -ovc frameno -nosound
subrip subtitles 0
where T is the title you want to rip, N is the subtitle number you want (see mplayer manpage), and is the output file for the subtitles.

Note that the gocr program is not very good at OCR, so you will definitely have to edit with a text editor and correct all of the character recognition mistakes that gocr makes. If the subtitles are not in a language that at least uses the Roman alphabet, then the gocr output is completely useless, but the times listed in the file should still be accurate.

The file is in SubRip (SRT) format, which can be converted to PPML as described in the conversion section.

3.3 Making your own script

In order to make your own script, you need to record all the lines of dialogue in the movie, translate them, and then record the start time and end time of each line so that you know when to have the subtitle appear and disappear. While the translation process is straightforward (assuming you know the language...), the task of timing the dialogue is almost impossible without specialized software to help you out. Here you have two options. You can use Windows software, which is what everybody else does, or you can be brave and try to do it in Linux as I describe below.

Obtaining a WAV file

You need to capture the audio from your DVD into a WAV file in order to be able to use the audio for timing. To do this, put the DVD into your drive and type:

mplayer -dvd 1 -vc null -vo null -ao pcm

to extract the audio from title number 1 into the file audiodump.wav (for another title number, change the number 1 to whatever number it is that you want). If your DVD title has multiple audio tracks, you may need to use some combination of the -alang or -aid options to get mplayer to extract the right audio track. You might also need to use the -chapter option if you only want to extract specific chapters.

Timing in Windows

To time the dialogue in windows, use the freeware Windows program Sub Station Alpha to time the dialogue from the above .wav file as described in the Sub Station Alpha documentation. The Karinkuru Guide To Subtitling also has many useful tips on how to use Sub Station Alpha for timing.

If you use Sub Station Alpha for timing then you will end up with a script in Sub Station Alpha format. You can then use mplayer to convert the resulting script into SRT format, as described here.

Timing in Linux

I have a separate page explaining the setup that I use for WAV timing in Linux. This procedure does work, and it is very easy for me to use, but most people will probably find it too hard to get running.

Another alternative is to use xste, which claims to perform WAV timing, but I have never gotten this software working.

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