====== Mplayer and mencoder ======

Mplayer was also very useful in extracting audio (AC3) and video (MPEG2) from a badly encoded DVD, see **[[dvd_ifo_errors]]**.

===== mplayer =====

=== -dvd-device <path to device> ===

Specifica il device DVD, predefinito ''**/dev/dvd**''. Si può indicare anche una directory che contiene i file precedentemente copiati dal DVD (ad esempio con ''**[[dvdbackup]]**'' o con ''**vobcopy**''). Di solito per copiare il contenuto di un DVD la via migliore è l'utilizzo dell'opzione ''**-dumpstream**''.

=== Selezione scheda ALSA per output audio ===

In questo esempio viene selezionata la seconda scheda audio (la prima ha il numero zero) per l'output:

<code>
mplayer -ao alsa:device=hw=1.0 file.avi
</code>

=== /dev/rtc ===

If you want to execute ''**mplayer**'' as non-privileged user, set ''/dev/rtc'' device to mode 0664. As far I know, this does not pose any security issuse. The usage of ''/dev/rtc'' can help synchronizing audio/video. Mplayer needs the ability to use high resolution timers, run this command as root every time your machine boots:

<code>
echo 1024 > /proc/sys/dev/rtc/max-user-freq
</code>

You can achieve the same result adding to ''**/etc/sysctl.conf**'' this line:

<file>
dev/rtc/max-user-freq=1024
</file>

=== /etc/mplayer/codecs.conf ===

Check that you have the latest version of the file. With the Debian Marillat package you get it into ''/usr/share/doc/mplayer-k6/examples/''. The same apply for the ''/etc/mplayer/mencoder_codecs.conf'' file.

==== Converting audio file with mplayer ====

In this example we will convert a **Microsoft ASF** audio file into a more usable **WAVE audio PCM**:

<code>
mplayer sample.asf -vo null -ao pcm:file=sample.wav
</code>

===== mencoder =====

==== How to extract subtitles from a DVD-Video into VobSub format ====

**A better way to convert DVD-Video subtitles** into VobSub format is to use **[[ripping_dvds_with_mencoder#subtitles|transcode]]**.

This is because mencoder seems to produce different image data into the ''**.sub**'' file and slightly different timestamps into the index (''**.idx**'') file depending on the used video codec (''-ovc'' option): strange enough, I got different outputs using //copy// and //raw// options. Transcode instead seems to be more deterministic.

We can use ''mplayer'' to identify subtitle streams contained into the DVD, they are identified by an ID and a language:

<code>
mplayer -dvd-device $RIPDIR dvd://$TITLE -identify
...
ID_SUBTITLE_ID=0
ID_SID_0_LANG=it
ID_SUBTITLE_ID=1
ID_SID_1_LANG=en
ID_SUBTITLE_ID=2
ID_SID_2_LANG=it
...
</code>

The following command will generate two files: ''**vobsubs-en.sub**'' and ''**vobsubs-en.idx**'' from the second subtitles stream (sid = 1).

<code>
mencoder -dvd-device $RIPDIR dvd://$TITLE \
    -nosound -ovc copy -o /dev/null \
    -ifo $RIPDIR/VIDEO_TS/VTS_01_0.IFO \
    -sid 1 -vobsubout vobsubs-en
</code>

With [[subtitleripper|vobsub2pgm]] you can convert VobSub subtitles into single .pgm images.

==== Ripping a DVD with mplayer ====

Sometimes trascoding a video DVD with **''avidemux''** (my favourite transcoding program) does not give correct results. I transcode the VOB files directly from the DVD, but the resulting video gets the multi-angle scenes interlaced. I think that the problem aroses from ''avidemux'' not being able to cope with [[wp>DVD-Video#Chapters_and_angles|DVD multi-angle scenes]].

**''mplayer''** instead plays the video correctly, so I use ''mplayer'' to extract a MPEG stream, and then I user ''avidemux'' to transcode.

First of all, we can play a DVD track from an .iso image mounted with the loop option. In this example we play track #27, using audio track ID 130 and no subtitles:

<code>
mount -o loop,ro dvdimage.iso /media/cdrom
mplayer dvd://27//media/cdrom -aid 130 -nosub
</code>

With this command we will dump track #27 to a raw compressed file, the file will contains all the audio tracks and subtitles:

<code>
mplayer dvd://27//media/cdrom -dumpstream -dumpfile dvd_track_27.vob
</code>

The dumped file can be played with ''mplayer'' or opened (and transcoded in XviD/mp3) with **''avidemux''**.