Vobsub subtitles extraction

encode2mpeg uses MEncoder to extract vobsub subtitles from a dvd. There are 3 options about vobsub dumping: -encsid -encsdx -encsla.
Look at this output of mplayer when accessing a dvd:
   INFO: [mplayer] [open] audio stream: 0 audio format: ac3 (5.1) language: en aid: 128
   INFO: [mplayer] [open] audio stream: 1 audio format: ac3 (5.1) language: fr aid: 129
   INFO: [mplayer] [open] number of audio channels on disk: 2.
   INFO: [mplayer] [open] subtitle ( sid ): 0 language: en
   INFO: [mplayer] [open] subtitle ( sid ): 1 language: fr
   INFO: [mplayer] [open] subtitle ( sid ): 2 language: es
   INFO: [mplayer] [open] number of subtitles on disk: 3
   INFO: [mplayer] ==> Found video stream: 0
   INFO: [mplayer] ==> Found audio stream: 129
   INFO: [mplayer] ==> Found audio stream: 128
   INFO: [mplayer] ==> Found subtitle: 5
   INFO: [mplayer] ==> Found subtitle: 4
   INFO: [mplayer] ==> Found subtitle: 3
   INFO: [mplayer] ==> Found subtitle: 2
   INFO: [mplayer] ==> Found subtitle: 1
   INFO: [mplayer] ==> Found subtitle: 0
As you can see the dvd says it has 3 subtitles 0 (en) 1 (fr) 2 (es), but when mplayer access the mpeg stream it sees 6 subtitles (0 to 5); further investigation shows that subtitles 0 and 1 are English, subtitles 2 and 3 are French, subtitles 4 and 5 are Spanish. The subtitles of the same language are identical. In this case you do not need to dump all the six subtitles, only three. If you want to dump the english, french, spanish subtitles you can't use
-ecnsid 0,1,2
 because it will dump two times the English subtitles plus the French one.
-encsid 0,2,4
will dump all the three different subtitles, but now they will have sid 0 2 4 and you want 0 1 2. In this case use:
-encsid 0,2,4 -encsdx 0,1,2
The subtitles will have the correct sid but the wrong slang: instead of "en fr es" it will be "en es xx"; in order to correct this use:
-encsid 0,2,4 -encsdx 0,1,2 -encsla en,fr,es

Note: you don't need to encode a movie in order to dump the subtitles:
encode2mpeg -o MyDump dvd://1 -avionly -encsid 0,1
will do the work. -encode is missing, so no encoding is done.