path: root/DOCS/xml/en/faq.xml

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<chapter id="faq" xreflabel="FAQ">
<title>Frequently Asked Questions</title>

<qandaset defaultlabel="qanda">

<qandadiv id="faq-development">
<title>Development</title>

<qandaentry>
<question><para>
How do I create a proper patch for <application>MPlayer</application>?
</para></question>
<answer><para>
OUTDATED CONTENT REMOVED
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How do I translate <application>MPlayer</application> to a new language?
</para></question>
<answer><para>
OUTDATED CONTENT REMOVED
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How can I support <application>MPlayer</application> development?
</para></question>
<answer><para>
OUTDATED CONTENT REMOVED
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How can I become an <application>MPlayer</application> developer?
</para></question>
<answer><para>
OUTDATED CONTENT REMOVED
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
Why don't you use autoconf/automake?
</para></question>
<answer><para>
We have a modular, handwritten build system. It does a reasonably good
job, so why change? Besides, we dislike the auto* tools, just like
<ulink url="http://freshmeat.net/articles/view/889/">other people</ulink>.
</para></answer>
</qandaentry>
</qandadiv>

<!-- ********** -->

<qandadiv id="faq-compilation-installation">
<title>Compilation and installation</title>

<qandaentry>
<question><para>
Compilation fails with an error and <application>gcc</application> bails out
with some cryptic message containing the phrase
<systemitem>internal compiler error</systemitem> or
<systemitem>unable to find a register to spill</systemitem> or
<systemitem>can't find a register in class `GENERAL_REGS'
while reloading `asm'</systemitem>.
</para></question>
<answer><para>
You have stumbled over a bug in <application>gcc</application>. Please
<ulink url="http://gcc.gnu.org/bugs.html">report it to the gcc team</ulink>
but not to us. For some reason <application>MPlayer</application> seems to
trigger compiler bugs frequently. Nevertheless we cannot fix them and do not
add workarounds for compiler bugs to our sources. To avoid this problem,
either stick with a compiler version that is known to be reliable and
stable, or upgrade frequently.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
Are there binary (RPM/Debian) packages of <application>MPlayer</application>?
</para></question>
<answer><para>
OUTDATED CONTENT REMOVED
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How can I build a 32 bit <application>MPlayer</application> on a 64 bit Athlon?
</para></question>
<answer><para>
OUTDATED CONTENT REMOVED
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
During 'make', <application>MPlayer</application> complains about
missing X11 libraries. I don't understand, I <emphasis>do</emphasis>
have X11 installed!?
</para></question>
<answer><para>
... but you don't have the X11 development package installed. Or not correctly.
It's called <filename>XFree86-devel*</filename> under Red Hat,
<filename>xlibs-dev</filename> under Debian Woody and
<filename>libx11-dev</filename> under Debian Sarge. Also check if the
<filename class="directory">/usr/X11</filename> and
<filename class="directory">/usr/include/X11</filename> symlinks exist.
</para></answer>
</qandaentry>

</qandadiv>

<!-- ********** -->

<qandadiv id="faq-general">
<title>General questions</title>

<qandaentry>
<question><para>
Are there any mailing lists on <application>MPlayer</application>?
</para></question>
<answer><para>
OUTDATED CONTENT REMOVED
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I've found a nasty bug when I tried to play my favorite video!
Who should I inform?
</para></question>
<answer><para>
OUTDATED CONTENT REMOVED
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How can I make a screenshot?
</para></question>
<answer><para>
You have to use a video output driver that does not employ an overlay to be
able to take a screenshot. Under X11, <option>-vo x11</option> will do, under
Windows <option>-vo directx:noaccel</option> works.
</para>
<para>
Alternatively you can run <application>MPlayer</application> with the
<systemitem>screenshot</systemitem> video filter
(<option>-vf screenshot</option>), and press the <keycap>s</keycap>
key to grab a screenshot.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
What is the meaning of the numbers on the status line?
</para></question>
<answer><para>
Example:
<screen>
A: 2.1 V: 2.2 A-V: -0.167 ct: 0.042 57/57 41% 0% 2.6% 0 4 49% 1.00x
</screen>
<variablelist>
<varlistentry>
  <term><systemitem>A: 2.1</systemitem></term>
  <listitem><para>audio position in seconds</para></listitem>
</varlistentry>
<varlistentry>
  <term><systemitem>V: 2.2</systemitem></term>
  <listitem><para>video position in seconds</para></listitem>
</varlistentry>
<varlistentry>
  <term><systemitem>A-V: -0.167</systemitem></term>
  <listitem><para>audio-video difference in seconds (delay)</para></listitem>
</varlistentry>
<varlistentry>
  <term><systemitem>ct: 0.042</systemitem></term>
  <listitem><para>total A-V sync correction done</para></listitem>
</varlistentry>
<varlistentry>
  <term><systemitem>57/57</systemitem></term>
  <listitem><para>
  frames played/decoded (counting from last seek)
  </para></listitem>
</varlistentry>
<varlistentry>
  <term><systemitem>41%</systemitem></term>
  <listitem><para>
  video codec CPU usage in percent
  (for slice rendering and direct rendering this includes video_out)
  </para></listitem>
</varlistentry>
<varlistentry>
  <term><systemitem>0%</systemitem></term>
  <listitem><para>video_out CPU usage</para></listitem>
</varlistentry>
<varlistentry>
  <term><systemitem>2.6%</systemitem></term>
  <listitem><para>audio codec CPU usage in percent</para></listitem>
</varlistentry>
<varlistentry>
  <term><systemitem>0</systemitem></term>
  <listitem><para>frames dropped to maintain A-V sync</para></listitem>
</varlistentry>
<varlistentry>
  <term><systemitem>4</systemitem></term>
  <listitem><para>
  current level of image postprocessing (when using <option>-autoq</option>)
  </para></listitem>
</varlistentry>
<varlistentry>
  <term><systemitem>49%</systemitem></term>
  <listitem><para>
  current cache size used (around 50% is normal)
  </para></listitem>
</varlistentry>
<varlistentry>
  <term><systemitem>1.00x</systemitem></term>
  <listitem><para>playback speed as a factor of original speed</para></listitem>
</varlistentry>
</variablelist>
Most of them are for debug purposes, use the <option>-quiet</option>
option to make them disappear.
You might notice that video_out CPU usage is zero (0%) for some files.
This is because it is called directly from the codec and thus cannot
be measured separately. If you wish to know the video_out speed, compare
the difference when playing the file with <option>-vo null</option> and
your usual video output driver.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
There are error messages about file not found
<filename>/usr/local/lib/codecs/</filename> ...
</para></question>
<answer><para>
OUTDATED CONTENT REMOVED
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How can I make <application>MPlayer</application> remember the options I
use for a particular file, e.g. <filename>movie.avi</filename>?
</para></question>
<answer><para>
Create a file named <filename>movie.avi.conf</filename> with the file-specific
options in it and put it in <filename class="directory">~/.mplayer</filename>.
Also see the manpage about <option>-use-filedir-conf</option>.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How can I run <application>MPlayer</application> in the background?
</para></question>
<answer><para>
Use:
<screen>
OUTDATED CONTENT REMOVED
</screen>
</para></answer>
</qandaentry>
</qandadiv>

<!-- ********** -->

<qandadiv id="faq-playback">
<title>Playback problems</title>

<qandaentry>
<question><para>
I cannot pinpoint the cause of some strange playback problem.
</para></question>
<answer><para>
Do you have a stray <filename>codecs.conf</filename> file in
<filename>~/.mplayer/</filename>, <filename>/etc/</filename>,
<filename>/usr/local/etc/</filename> or a similar location? Remove it,
an outdated <filename>codecs.conf</filename> file can cause obscure
problems and is intended for use only by developers working on codec
support. It overrides <application>MPlayer</application>'s internal
codec settings, which will wreak havoc if incompatible changes are
made in newer program versions. Unless used by experts it is a recipe
for disaster in the form of seemingly random and very hard to localize
crashes and playback problems. If you still have it somewhere on your
system, you should remove it now.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How can I get subtitles to appear on the black margins around a movie?
</para></question>
<answer><para>
OUTDATED CONTENT REMOVED
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How can I select audio/subtitle tracks from a DVD, OGM, Matroska or NUT file?
</para></question>
<answer><para>
You have to use <option>-aid</option> (audio ID) or <option>-alang</option>
(audio language), <option>-sid</option>(subtitle ID) or <option>-slang</option>
(subtitle language), for example:
<screen>
mplayer -alang eng -slang eng <replaceable>example.mkv</replaceable>
mplayer -aid 1 -sid 1 <replaceable>example.mkv</replaceable>
</screen>
To see which ones are available:
<screen>
mplayer -vo null -ao null -frames 0 -v <replaceable>filename</replaceable> | grep sid
mplayer -vo null -ao null -frames 0 -v <replaceable>filename</replaceable> | grep aid
</screen>
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I downloaded a movie off a P2P network and it doesn't work!
</para></question>
<answer><para>
Your file is most probably broken or a fake file. If you got it from
a friend, and he says it works, try comparing
<application>md5sum</application> hashes.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I'm having trouble getting my subtitles to display, help!!
</para></question>
<answer><para>
OUTDATED CONTENT REMOVED
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
<application>MPlayer</application> dies with
<screen>MPlayer interrupted by signal 4 in module: decode_video</screen>
</para></question>
<answer><para>
Don't use <application>MPlayer</application> on a CPU different from the one
it was compiled on or recompile with runtime CPU detection
OUTDATED CONTENT REMOVED
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
When I try to grab from my tuner, it works, but colors are strange.
It's OK with other applications.
</para></question>
<answer><para>
Your card probably reports some colorspaces as supported when in fact
it does not support them. Try with YUY2 instead of the
default YV12 (see the <link linkend="tv-input">TV</link> section).
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
While playing a movie it suddenly gets jerky and I get the following message:
<screen>Badly interleaved AVI file detected - switching to -ni mode...</screen>
</para></question>
<answer><para>
Badly interleaved files and <option>-cache</option> don't work well together.
Try <option>-nocache</option>.
</para></answer>
</qandaentry>
</qandadiv>

<!-- ********** -->

<qandadiv id="faq-driver">
<title>Video/audio driver problems (vo/ao)</title>

<qandaentry>
<question><para>
When I go into fullscreen mode I just get black borders around the image
and no real scaling to fullscreen mode.
</para></question>
<answer><para>
Your video output driver does not support scaling in hardware and since
scaling in software can be incredibly slow <application>MPlayer</application>
does not automatically enable it. Most likely you are using the
<systemitem>x11</systemitem> instead of the <systemitem>xv</systemitem>
video output driver. Try adding <option>-vo xv</option> to the command
line or read the <link linkend="video">video section</link> to find out
about alternative video output drivers. The <option>-zoom</option>
option explicitly enables software scaling.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I've just installed <application>MPlayer</application>. When I want to
open a video file it causes a fatal error:
<screen>Error opening/initializing the selected video_out (-vo) device.</screen>
How can I solve my problem?
</para></question>
<answer><para>
Just change your video output device. Issue the following command to get
a list of available video output drivers:
<screen>mplayer -vo help</screen>
After you've chosen the correct video output driver, add it to
your configuration file. Add
<programlisting>
vo = <replaceable>selected_vo</replaceable>
</programlisting>
to <filename>~/.mplayer/config</filename>
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I have problems with <replaceable>[your window manager]</replaceable>
and fullscreen xv/xmga/sdl/x11 modes ...
</para></question>
<answer><para>
Read the <link linkend="bugreports">bug reporting guidelines</link> and send us
a proper bug report.
Also try experimenting with the <option>-fstype</option> option.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How can I use <application>dmix</application> with
<application>MPlayer</application>?
</para></question>
<answer><para>
After setting up your
<ulink url="http://alsa.opensrc.org/index.php?page=DmixPlugin">asoundrc</ulink>
you have to use <option>-ao alsa:device=dmix</option>.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I have no sound when playing a video and get error messages similar to this one:
<screen>
AO: [oss] 44100Hz 2ch Signed 16-bit (Little-Endian)
[AO OSS] audio_setup: Can't open audio device /dev/dsp: Device or resource busy
Could not open/initialize audio device -> no sound.
Audio: no sound
Starting playback...
</screen>
</para></question>
<answer><para>
Are you running KDE or GNOME with the aRts or ESD sound daemon? Try disabling
the sound daemon or use the <option>-ao arts</option> or
<option>-ao esd</option> option to make <application>MPlayer</application> use
aRts or ESD.
You might also be running ALSA without OSS emulation, try loading the ALSA OSS
kernel modules or add <option>-ao alsa</option> to your command line to
directly use the ALSA audio output driver.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
When starting <application>MPlayer</application> under KDE I just get a black
screen and nothing happens. After about one minute the video starts playing.
</para></question>
<answer><para>
The KDE aRts sound daemon is blocking the sound device. Either wait until the
video starts or disable the aRts daemon in control center. If you want to use
aRts sound, specify audio output via our native aRts audio driver
(<option>-ao arts</option>). If it fails or isn't compiled in, try SDL
(<option>-ao sdl</option>) and make sure your SDL can handle aRts sound. Yet
another option is to start <application>MPlayer</application> with artsdsp.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I have A/V sync problems.
Some of my AVIs play fine, but some play with double speed!
</para></question>
<answer><para>
You have a buggy sound card/driver. Most likely it's fixed at 44100Hz, and you
try to play a file which has 22050Hz audio. Try the
<systemitem>resample</systemitem> audio filter.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How can I get rid of A/V desynchronization
while seeking through RealMedia streams?
</para></question>
<answer><para>
<option>-mc 0.1</option> can help.
</para></answer>
</qandaentry>
</qandadiv>

<!-- ********** -->

<qandadiv id="faq-dvd">
<title>DVD playback</title>

<qandaentry>
<question><para>
What about DVD navigation/menus?
</para></question>
<answer><para>
<application>MPlayer</application> should support DVD menus nowadays.
Your mileage may vary.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
What about subtitles? Can <application>MPlayer</application> display them?
</para></question>
<answer><para>
Yes. See the <link linkend="dvd">DVD chapter</link>.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How can I set the region code of my DVD-drive? I don't have Windows!
</para></question>
<answer><para>
Use the
<ulink url="http://linvdr.org/projects/regionset/">regionset tool</ulink>.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I can't play a DVD, MPlayer hangs or outputs "Encrypted VOB file!" errors.
</para></question>
<answer><para>
CSS decryption code does not work with some DVD drives unless you set
the region code appropriately. See the answer to the previous question.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
Do I need to be (setuid) root to be able to play a DVD?
</para></question>
<answer><para>
No. However you must have the proper rights
on the DVD device entry (in <filename class="directory">/dev/</filename>).
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
Is it possible to play/encode only selected chapters?
</para></question>
<answer><para>
Yes, try the <option>-chapter</option> option.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
My DVD playback is sluggish!
</para></question>
<answer><para>
Use the <option>-cache</option> option (described in the man page) and try
enabling DMA for the DVD drive with the <command>hdparm</command> tool.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I copied a DVD using vobcopy. How do I play/encode it from my hard disk?
</para></question>
<answer><para>
Use the <option>-dvd-device</option> option to refer to the directory
that contains the files:
<screen>
mplayer dvd://1 -dvd-device <replaceable>/path/to/directory</replaceable>
</screen>
</para></answer>
</qandaentry>
</qandadiv>


<qandadiv id="faq-features">
<title>Feature requests</title>

<qandaentry>
<question><para>
I'd like to seek +/- 1 frame instead of 10 seconds.
</para></question>
<answer><para>
You can step forward one frame by pressing <keycap>.</keycap>.
If the movie was not paused it will be paused afterwards
(see the man page for details).
Stepping backwards is not currently implemented, but note that you can make
small seeks using the <option>-hr-seek</option> functionality.
</para></answer>
</qandaentry>
</qandadiv>

<!-- ********** -->

<qandadiv id="faq-encoding">
<title>Encoding</title>

<para>
OUTDATED CONTENT REMOVED
</para>
</qandadiv>

</qandaset>

</chapter>