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====== MEncoder ======

''mencoder'' is the video/audio transcoding utility shipped with ''mplayer''.
Like the player, it's a very mighty utility, perfectly performing the tasks it
was designed for.

===== DVD Ripping =====

This is how I used to rip my DVDs using ''mencoder'' (meanwhile I switched to using [[util:multimedia:ffmpeg#Encoding_Videos|ffmpeg]]:

==== Information to have at hand when beginning ====
  * title (and maybe chapters) which are to be ripped
  * start/end offsets of movie if parts of the title are crap
  * necessary cropping values
  * the original aspect ratio of the movie
  * the desired audio track's id
  * original number of audio channels, and number of channels to encode to
  * subtitle id if needed

==== Ripping The Audio Track ====
<code>
% mencoder dvd://3 -aid 129 -ss 0:03:18 -af pan=2:1:0:0:1:1:0:0:1:0.5:0.5:0.5:0.5 \
	-ovc frameno -o frameno.avi -oac mp3lame -lameopts vbr=2
</code>
  * **dvd:<nowiki>//</nowiki>3** specifies the title
  * **-aid 129** selects the second audio track
  * **-ss 0:03:18** starts ripping 3 minutes, 18 seconds after the original beginning
  * **-channels 6** force using six channels, so they can be customly mapped
  * **-af pan=2:1:0:0:1:1:0:0:1:0.5:0.5:0.5:0.5** output to 2 channels, map lf to l, rf to r, lb to l, rb to r, split center and subwoofer by half volume to l and r
  * **-ovc frameno** special video codec containing just audio
  * **-o frameno.avi** target filename, must be exactly like this
  * **-oac mp3lame** encode audio to mp3 using lame
  * **-lameopts vbr=2** encode to VBR
when ''mencoder'' finishes encoding audio, it will output some hints for later
choice of video bitrate, pasting them to a temporary place is a good idea.

==== First Pass Of Encoding ====
<code>
% mencoder -dvd-device NBK_18 dvd://3 -ss 0:03:18 -oac copy -o /dev/null -ovc lavc \
	-lavcopts vcodec=mpeg4:vbitrate=1400:vhq:vqmin=2:vqmax=31:aspect=16/9:threads=4:vpass=1 \
	-vf crop=710:430
</code>
  * **-oac copy** ''mencoder'' uses the file ''frameno.avi'' for audio, which is already perfectly encoded
  * **-o /dev/null** discard output, this run is just for getting some file information
  * **-ovc lavc** use ''lavc'' for encoding to avi
  * **-lavcopts vcodec=mpeg4:vbitrate=1400:vhq:vqmin=2:vqmax=31:aspect=16/9:threads=4:vpass=1** encode to mpeg4, 1400bit/s, enable high quality, set minimum/maximum compression to 2/31, encode aspect ratio in file (only supported by ''mplayer''), encode using four threads and set pass to first one
  * **-vf crop=710:430** crop to 710x430 video aspect

==== Second Pass Of Encoding ====
<code>
% mencoder -dvd-device NBK_18 dvd://3 -ss 0:03:18 -oac copy -o target_filename.avi -ovc lavc \
	-lavcopts vcodec=mpeg4:vbitrate=1400:vhq:vqmin=2:vqmax=31:aspect=16/9:threads=4:vpass=3 \
	-vf crop=710:430
</code>
  * **-o target_filename.avi** from now on, actually write to a file
  * **vpass=3** set this to be pass 2-N of an N-Pass encoding run

==== Third And Subsequent Passes Of Encoding ====
Just repeat the second pass to achieve better results. Doing this more than
four times is said to not help really much anymore.

==== Hints ====
To speed up or allow delayed encoding of a DVD, it's content is best copied to
disk. I do this using ''vobcopy''. Just create and change into a new directory,
then run:
<code>
% vobcopy -m -i /mnt/dvd
</code>
where ///mnt/dvd// is the path to the mounted DVD drive. To allow
''mplayer''/''mencoder'' to operate on the ripped files on disk, the option
''-dvd-device /path/to/rip'' can be used.

===== Converting Audio Tracks =====

Not as easy as one may think, at least ''mencoder'' itself didn't let me do
it. But luckily ''mplayer'' does the job:
<code>
% mplayer -ao pcm:file="audiotrack.pcm" -vo null audiotrack.m4a
</code>
for encoding I then simply use lame:
<code>
% lame -m s -q 2 --vbr-new -V 3 audiotrack.pcm audiotrack.mp3
</code>

===== Encoding to SVCD =====

DivX support in many DVD players is still completely broken. So instead of
trying to find the right DivX encoding parameters for each DVD player device
out there separately, using a well-known (and also well-supported) video
format instead seems to be more practical. And this is where good old SVCD
comes into play.

===== Links =====
[[http://www.bunkus.org/dvdripping4linux/single/index.html|Extensive DVD Ripping Howto]]
[[http://www.mplayerhq.hu/DOCS/HTML/de/menc-feat-vcd-dvd.html|Encoding to VCD,
SVCD or DVD]]