mpv/DOCS/xml/en/faq.xml

<?xml version="1.0" encoding="iso-8859-1"?>
<!-- $Revision$ -->
<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>
We made a <ulink url="../../tech/patches.txt">short document</ulink>
describing all the necessary details. Please follow the instructions.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How do I translate <application>MPlayer</application> to a new language?
</para></question>
<answer><para>
Read the <ulink url="../../tech/translations.txt">translation HOWTO</ulink>,
it should explain everything. You can get further help on the
<ulink url="http://mplayerhq.hu/mailman/listinfo/mplayer-docs">MPlayer-docs</ulink>
mailing list.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How can I support <application>MPlayer</application> development?
</para></question>
<answer><para>
We are more than happy to accept your hardware and software
<ulink url="http://www.mplayerhq.hu/homepage/donations.html">donations</ulink>.
They help us in continuously improving <application>MPlayer</application>.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How can I become an <application>MPlayer</application> developer?
</para></question>
<answer><para>
We always welcome coders and documenters. Read the
<ulink url="../../tech/">technical documentation</ulink>
to get a first grasp. Then you should subscribe to the
<ulink url="http://mplayerhq.hu/mailman/listinfo/mplayer-dev-eng">MPlayer-dev-eng</ulink>
mailing list and start coding. If you want to help out with the documentation,
join the
<ulink url="http://mplayerhq.hu/mailman/listinfo/mplayer-docs">MPlayer-docs</ulink>
mailing list.
</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">
<title>Compilation</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>.
</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/deb) packages of <application>MPlayer</application>?
</para></question>
<answer><para>
See the <link linkend="debian">Debian</link> and <link linkend="rpm">RPM</link>
section for details.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How can I build a 32 bit <application>MPlayer</application> on 64 bit Athlon?
</para></question>
<answer><para>
Try the following configure options:
<screen>
./configure --target=athlon_xp --cc="gcc -m32" --as="as --32" --with-extralibdir=/usr/lib
</screen>
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
Compilation stops with an error message similar to this one:
<screen>
    cfft.c: In function`passf2':
    cfft.c:556: unable to find a register to spill in class `FLOAT_REGS'
    cfft.c:556: this is the insn:
    (insn 235 233 246 (set (subreg:SF (reg/v:DI 29 rmm0 [110]) 0)
            (minus:SF (mem:SF (plus:SI (mult:SI (reg:SI 1 edx [112])
                            (const_int 8 [0x8]))
                        (reg/v/f:SI 3 ebx [62])) [4 S4 A32])
                (reg:SF 8 st(0) [132]))) 533 {*fop_sf_1_nosse} (insn_list
    232 (nil))    (expr_list:REG_DEAD (reg:SF 8 st(0) [132])
            (nil)))
    cfft.c:556: confused by earlier errors, bailing out
</screen>
</para></question>
<answer><para>
This is a known problem of <application>gcc</application> 3.2, upgrade
to 3.3 to solve the problem. How to install gcc is described in the
<link linkend="gcc-296">gcc 2.96</link> section. Alternatively you can use
an external FAAD library as described in the
<link linkend="aac">AAC</link> section.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
Compilation stops with an error message similar to this one:
<screen>
    In file included from mplayer.c:34:
    mw.h: In function `mplMainDraw':
    mw.h:209: Internal compiler error in print_rtl_and_abort, at flow.c:6458
    Please submit a full bug report,
    with preprocessed source if appropriate.
</screen>
</para></question>
<answer><para>
This is a known problem of <application>gcc</application> 3.0.4, upgrade
to 3.1 to solve the problem. How to install gcc is described in the
<link linkend="gcc-296">gcc 2.96</link> section.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
Configure ends with this text, and <application>MPlayer</application> won't compile!
<screen>Your gcc does not support even i386 for '-march' and '-mcpu'</screen>
</para></question>
<answer><para>
Your gcc isn't installed correctly, check the <filename>configure.log</filename>
file for details.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
What's the problem with gcc 2.96?
</para></question>
<answer><para>
<emphasis role="bold">We strongly discourage the use of gcc 2.96!</emphasis>
Read <link linkend="gcc-296">this</link> document for details about why Red Hat
released gcc 2.96 and what the problems are all about. If you still really really
want to use it, be sure to get the latest release and give the
<option>--disable-gcc-checking</option> option to configure. Remember that you
are on your own from this point. Do <emphasis role="bold">not</emphasis> report
bugs, do <emphasis role="bold">not</emphasis> ask for help on the mailing lists.
We will <emphasis role="bold">not</emphasis> provide any support in case you run
into problems.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
Great, I have gcc 3.0.1 from Red Hat/Mandrake, then I'm fine!
</para></question>
<answer><para>
No, since there have been/are issues with these compilers as well.
To check the status of current compilers' <application>MPlayer</application>
support, see the <link linkend="install">Installation</link> section.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
.. gcc 2.96 ... (Yes, some people are STILL flaming about gcc 2.96!)
</para></question>
<answer><para>
Quoted from a <ulink url="http://www.mplayerhq.hu/pipermail/mplayer-users/2001-October/005351.html">mail</ulink>
A'rpi sent to the <ulink url="http://mplayerhq.hu/pipermail/mplayer-users/">MPlayer-users</ulink>
list (the word 'ideg' is described below):
<blockquote>
<para>
And we have idegs. And our idegcounter overflowed again and again.
</para>
<para>
Unfortunately <application>MPlayer</application> is out of our control.
It's used by lamers, Linux users who can't even use Windows, and never
tried to compile a kernel. They installed (with default options) Mandrake
or Red Hat or SuSE, and without RTFM'ing they send messages saying
'it doesn't work! help me! please! i'm new to Linux! help! oh! help me!'.
We can't stop them, but at least we try to force them to RTFM and to read
the messages of ./configure and <application>MPlayer</application>.
</para>
<para>
And you clever guys come and flame us with gcc 2.96 and binary packages.
Instead of helping users or making patches to help solve problems.
</para>
<para>
Half of our spare/free time is spent by answering silly mails here and
making newer tricks and checks to configure to avoid such mails.
</para>
<para>
And there is a balance. On the one side are you, clever guys, saying we
are very bad because we don't like buggy gcc 2.96, and on the other side
there are the 'new to Linux' guys who are showing us gcc 2.96 is buggy.
</para>
<para>
Conclusion: We can't be good. Half the people will always say we are bad.
</para>
<para>
Maybe we should close the project, make it closed source, commercial, and
provide install support for it. then we could leave current work, so development
could go faster, and we could earn lots of money with it and buy a big house,
etc etc. Do you really want it? It seems.
</para>
</blockquote>
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
SDL output doesn't work or compile. The problem is ...
</para></question>
<answer><para>
It was tested to work with SDL 1.2.x and may run on SDL 1.1.7+. It does
<emphasis role="bold">not</emphasis> work with any previous version. So
if you choose to use such a version, you are on your own.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I am still having trouble compiling with SDL support. gcc says something
about <screen>undefined reference to SDL_EnableKeyRepeat</screen>. What now?
</para></question>
<answer><para>
Where did you install the SDL library? If you installed in
<filename class="directory">/usr/local</filename> (the default) then edit the
top level <filename>config.mak</filename> and add
<systemitem>-L/usr/local/lib</systemitem> after <systemitem>X_LIBS=</systemitem>.
Now type <command>make</command>. You're done!
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I have a Matrox G200/G400/G450/G550, how do I compile/use the mga_vid driver?
</para></question>
<answer><para>
Read the <link linkend="mga_vid">mga_vid</link> section.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
During 'make', <application>MPlayer</application> complains about X11 libraries.
I don't understand, I DO have X installed!?
</para></question>
<answer><para>
... but you don't have the X development package installed. Or not correctly.
It's called <filename>XFree86-devel*</filename> under Red Hat, and
<filename>xlibs-dev</filename> under Debian Woody,
<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 (this
can be a problem on Mandrake systems). They can be created with these commands:
<screen>
     # ln -sf /usr/X11R6 /usr/X11
     # ln -sf /usr/X11R6/include/X11 /usr/include/X11
</screen>
Your distribution may differ from the
<ulink url="http://www.pathname.com/fhs/">Filesystem Hierarchy Standard</ulink>.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I can't compile SVGAlib. I'm using kernel 2.3/2.4 ...
</para></question>
<answer><para>
You have to edit SVGAlib's <filename>Makefile.cfg</filename> and comment
<systemitem>BACKGROUND = y</systemitem> out.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I compiled <application>MPlayer</application> with libdvdcss/libdivxdecore support,
but when I try to start it, it says:
<screen>
error while loading shared libraries: lib*.so.0: cannot load shared object file: No such file or directory
</screen>
I checked up on the file and it IS there in <filename class="directory">/usr/local/lib</filename> ...
</para></question>
<answer><para>
Add <filename class="directory">/usr/local/lib</filename> to <filename>/etc/ld.so.conf</filename>
and run <command>ldconfig</command>.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
When compiling <application>MEncoder</application>, it segfaults at linking!
</para></question>
<answer><para>
This is a linker problem. Upgrading binutils should help (2.11.92.*
or newer should be good). Since it is not our fault, please do
<emphasis role="bold">not</emphasis> report!
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
<application>MPlayer</application> dies with segmentation fault upon pthread check!
</para></question>
<answer><para>
<command>chmod 644 /usr/lib/libc.so</command>
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I'd like to compile <application>MPlayer</application> on Minix!
</para></question>
<answer><para>
Me too. :)
</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>
Yes. See the <link linkend="mailinglists">mailing lists</link>
section.
</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>
Please read the
<link linkend="bugreports">bug reporting guidelines</link>
and follow the instructions.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I have problems playing files with the ... codec. Can I use them?
</para></question>
<answer><para>
Check the <ulink url="../../codecs-status.html">codec status</ulink>,
if it doesn't contain your codec, read the <link linkend="codecs">codec documentation</link>,
especially the <link linkend="codec-importing">codec importing HOWTO</link> and contact us.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
When I start playing, I get this message but everything seems fine:
<screen>Linux RTC init: ioctl (rtc_pie_on): Permission denied</screen>
</para></question>
<answer><para>
You need root privileges or a specially set up kernel to use the new timing
code. For details see the <link linkend="rtc">RTC</link> section of the documentation.
</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></answer>
</qandaentry>

<qandaentry>
<question><para>
There is a timer in the upper left corner. How can I get rid of it?
</para></question>
<answer><para>
Press <keycap>o</keycap> and try the <option>-osdlevel</option> option.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
The <option>-xy</option> or <option>-fs</option> option doesn't work with
the x11 driver (<option>-vo x11</option>) ...
</para></question>
<answer><para>
It does, but you have to explicitly specify software scaling (very slow) with the
<option>-zoom</option> option. You better use XF86VidMode support: You must
specify the <option>-vm</option> and the <option>-fs</option> option, and you're
done. Make sure you have the right modelines in your <filename>XF86Config</filename>
file, and try to make the <link linkend="dga">DGA driver</link> and
<link linkend="sdl">SDL's DGA driver</link> work for you. It's much
faster. If SDL's DGA works, use that, it'll be even faster.
</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%</screen>
<itemizedlist>
<listitem><para>A: audio position in seconds</para></listitem>
<listitem><para>V: video position in seconds</para></listitem>
<listitem><para>A-V: audio-video difference in seconds (delay)</para></listitem>
<listitem><para>ct: total A-V sync correction done</para></listitem>
<listitem><para>frames played (counting from last seek)</para></listitem>
<listitem><para>frames decoded (counting from last seek)</para></listitem>
<listitem><para>video codec CPU usage in percent (for slices and DR this includes
video_out)</para></listitem>
<listitem><para>video_out CPU usage</para></listitem>
<listitem><para>audio codec CPU usage in percent</para></listitem>
<listitem><para>frames needed to drop to maintain A-V sync</para></listitem>
<listitem><para>current level of image postprocessing (when using
<option>-autoq</option>)</para></listitem>
<listitem><para>current cache size used (around 50% is normal)</para></listitem>
<listitem><para>playback speed as a factor of original speed</para></listitem>
</itemizedlist>
Most of them are for debug purposes and will be removed at some point.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
What if I don't want them to appear?
</para></question>
<answer><para>
Use the <option>-quiet</option> option and read the man page.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
Why is video_out CPU usage zero (0%) for some files?
</para></question>
<answer><para>
It's not zero, but it's called from the codec and thus cannot be measured
separately. You should try to play the file using <option>-vo null</option> and
then <option>-vo ...</option> and check the difference to see the video_out speed.
</para></answer>
<answer><para>
You are using Direct Rendering, where the codec renders to the video memory
itself. In this case, the decoding percentage contains the display percentage, too.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
There are error messages about file not found <filename>/usr/local/lib/codecs/</filename> ...
</para></question>
<answer><para>
Download the Win32 codecs from our
<ulink url="http://www.mplayerhq.hu/MPlayer/releases/codecs/">codecs page</ulink>
(avifile's codec package has a different DLL set) and install it.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
Umm, what is &quot;IdegCounter&quot;?
</para></question>
<answer><para>
A combination of a Hungarian and an English word. &quot;Ideg&quot; in Hungarian
means the same as &quot;nerve&quot; in English, and is pronounced as something like
&quot;ydaegh&quot;. It was first used to measure the nervousness of A'rpi, after
some (umm) &quot;mysterious&quot; disappearance of CVS code ;)
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
And what is &quot;Faszom(C)ounter&quot;?
</para></question>
<answer><para>
&quot;Fasz&quot; is a Hungarian word you don't want to know, the others are
connected to the perverted minds of the <application>MPlayer</application> developers.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
Subtitles are very nice, the most beautiful I've ever seen, but they
slow down playing! I know it's unlikely ...
</para></question>
<answer><para>
After running <filename>./configure</filename>, edit <filename>config.h</filename>
and replace <systemitem>#undef FAST_OSD</systemitem> with
<systemitem>#define FAST_OSD</systemitem>. Then recompile.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
What exactly is this <systemitem class="library">libavcodec</systemitem> thing?
</para></question>
<answer><para>
See the
<link linkend="ffmpeg"><systemitem class="library">libavcodec</systemitem></link>
section.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
But configure tells me
<screen>Checking for libavcodec ... no</screen>
</para></question>
<answer><para>
You need to get <systemitem class="library">libavcodec</systemitem> from
FFmpeg's CVS. Read the instructions in the
<link linkend="ffmpeg"><systemitem class="library">libavcodec</systemitem></link>
section.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I can't access the GUI menu. I press right click, but I can't
access any menu items!
</para></question>
<answer><para>
Are you using FVWM? Try the following:
<orderedlist>
<listitem><para>Start -> Settings -> Configuration -> Base Configuration</para></listitem>
<listitem><para>Set <systemitem>Use Applications position hints</systemitem>
to <systemitem>Yes</systemitem></para></listitem>
</orderedlist>
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How can I run <application>MPlayer</application> in the background?
</para></question>
<answer><para>
Use:
<screen>mplayer <replaceable>options</replaceable> <replaceable>filename</replaceable> &lt; /dev/null &amp;</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 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 example.mkv -alang eng -slang eng
mplayer example.mkv -aid 1 -sid 1
</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'm trying to play a random stream off the internet but it fails.
</para></question>
<answer><para>
Try playing the stream with the <option>-playlist</option> option.
</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'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> and/or
<programlisting>
vo_driver = <replaceable>selected_vo</replaceable>
</programlisting>
to <filename>~/.mplayer/gui.conf</filename>.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I'm having trouble getting my subtitles to display, help!!
</para></question>
<answer><para>
Make sure you have installed fonts properly. Run through the steps in the
<link linkend="mpsub-install">OSD and subtitle</link> part of the installation
section again. If you are using TrueType fonts, verify that you have the
<systemitem class="library">FreeType</systemitem> library installed.
Other things include checking your subtitles in a text editor or with other
players. Also try converting them to another format.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
Why doesn't <application>MPlayer</application> work on Fedora Core?
</para></question>
<answer><para>
There is a bad interaction on Fedora between exec-shield,
prelink, and any applications which use Windows DLLs
(such as <application>MPlayer</application>).
</para>
<para>
The problem is that exec-shield randomizes the load addresses of all the
system libraries. This randomization happens at prelink time (once every
two weeks).
</para>
<para>
When <application>MPlayer</application> tries to load a Windows DLL it
wants to put it at a specific address (0x400000). If an important system
library happens to be there already, <application>MPlayer</application>
will crash.
(A typical symptom would be a segmentation fault when trying
to play Windows Media 9 files.)
</para>
<para>
If you run into this problem you have two options:
<itemizedlist>
<listitem><para>Wait two weeks. It might start working again.</para></listitem>
<listitem><para>Relink all the binaries on the system with different
prelink options. Here are step by step instructions:</para>
<para>
<orderedlist>
<listitem><para>Edit <filename>/etc/syconfig/prelink</filename> and change</para>
<para>
<programlisting>
PRELINK_OPTS=-mR
</programlisting>
</para>
<para>
to
<programlisting>
PRELINK_OPTS="-mR --no-exec-shield"
</programlisting>
</para>
</listitem>
<listitem><para><command>touch /var/lib/misc/prelink.force</command></para></listitem>
<listitem><para><command>/etc/cron.daily/prelink</command>
(This relinks all the applications, and it takes
quite a while.)</para></listitem>
<listitem>
<para><command>execstack -s <replaceable>/path/to/</replaceable>mplayer</command>
(This turns off exec-shield for the <application>MPlayer</application> binary.)
</para>
</listitem>
</orderedlist>
</para>
</listitem>
</itemizedlist>
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
... works with <application>xine/vlc/...</application> but doesn't with
<application>MPlayer</application>.
</para></question>
<answer><para>
<application>MPlayer</application> is not <application>xine/vlc/...</application>.
Although these players have some code in common, the codecs (DLL) set,
synchronization, demultiplexing etc is different and should not be
compared. If you have a file <application>MPlayer</application> fails to
play correctly but works in another player, please read the
<link linkend="bugreports">bug reporting guidelines</link> and upload
the file to our FTP server.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
Audio goes out of sync playing an AVI file.
</para></question>
<answer><para>
Try the <option>-bps</option> or <option>-nobps</option> option. If it does not
improve, read the
<link linkend="bugreports">bug reporting guidelines</link>
and upload the file to FTP.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
<application>MPlayer</application> exits with some error when using <filename>l3codeca.acm</filename>.
</para></question>
<answer><para>
Check <command>ldd /usr/local/bin/mplayer</command> output. If it contains
<screen>libc.so.6 => /lib/libc.so.6 (0x4???????)</screen>
where &quot;?&quot; is any number then it's OK, the error is not here. If it is:
<screen>libc.so.6 => /lib/libc.so.6 (0x00??????)</screen>
then there is a problem with your kernel/libc. Maybe you are using some security
patches (for example Solar Designer's OpenWall patch) which forces loading
libraries to very low addresses. Because <filename>l3codeca.acm</filename> is a
non-relocatable DLL, it must be loaded to <literal>0x40000000</literal>, we can't
change this. You should use a non-patched kernel, or use <application>MPlayer</application>'s
<option>-afm 1</option> option to disable using <filename>l3codeca.acm</filename>.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
My computer plays MS DivX AVIs with resolutions ~ 640x300 and stereo MP3 sound
too slow. When I use <option>-nosound</option> option, everything is OK (but quiet).
</para></question>
<answer><para>
Your machine is too slow or your sound card driver is broken. Consult the
documentation to see if you can improve performance.
</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>
Try running <application>MPlayer</application> on the machine you compiled on.
Or recompile with runtime CPU detection
(<command>./configure --enable-runtime-cpudetection</command>).
Don't use <application>MPlayer</application> on a CPU different from the one
it was compiled on, without using the feature mentioned just now.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I have problems with [your window manager] 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>
I got this playing MPEG files: Can't find codec for video format 0x10000001!
</para></question>
<answer><para>
You have an old version of <filename>codecs.conf</filename> in
<filename class="directory">~/.mplayer/</filename>,
<filename class="directory">/etc/</filename>,
<filename class="directory">/usr/local/etc/</filename> or similar. Remove it,
it's not needed anymore.
<emphasis role="bold">OR</emphasis> you have the <option>vc=</option> option or
something similar in your config file(s).
</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 an AVI that produces a gray screen when played with <option>-vc odivx</option>
and a green one with <option>-vc divx4</option>.
</para></question>
<answer><para>
It's not a DivX file, but an MS MPEG4v3.
If you have an old version of <filename>codecs.conf</filename> in
<filename class="directory">~/.mplayer/</filename>,
<filename class="directory">/etc/</filename>,
<filename class="directory">/usr/local/etc/</filename> or similar, remove it.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
When I play this movie I get video-audio desync and/or <application>MPlayer</application>
crashes with the following message:
<screen>DEMUXER: Too many (945 in 8390980 bytes) video packets in the buffer!</screen>
</para></question>
<answer><para>
This can have multiple reasons.
<itemizedlist>
<listitem><para>
Your CPU <emphasis role="bold">and/or</emphasis> video card <emphasis role="bold">and/or</emphasis>
bus is too slow. <application>MPlayer</application> displays a message if this is the case (and the
dropped frames counter goes up fast).
</para></listitem>
<listitem><para>
If it is an AVI, maybe it has bad interleaving. Try the <option>-ni</option> option.
</para></listitem>
<listitem><para>
Your sound driver is buggy, or you use ALSA 0.5 with <option>-ao oss</option>.
See the <link linkend="audio">sound card section</link>.
</para></listitem>
<listitem><para>
The AVI has a bad header, try the <option>-nobps</option> option, and/or <option>-mc 0</option>.
</para></listitem>
</itemizedlist>
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I have an MJPEG file which works with other players but displays only a black image in
<application>MPlayer</application>
</para></question>
<answer><para>
Use another codec to play the file, try <option>-vc ffmjpeg</option>.
</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>
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 resample audio filter.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
All the WMV (or other..) files I play create a green/gray window and there is
only sound! <application>MPlayer</application> prints:
<screen>Detected video codec: [null] drv:0 (NULL codec (no decoding))</screen>
</para></question>
<answer><para>
If you have an old version of <filename>codecs.conf</filename> in
<filename class="directory">~/.mplayer/</filename>,
<filename class="directory">/etc/</filename>,
<filename class="directory">/usr/local/etc/</filename> or similar, remove it.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I get very strange percentage values (way too big) while playing files on my notebook.
</para></question>
<answer><para>
It's an effect of the power management / power saving system of your notebook
(BIOS, not kernel). Plug the external power connector in
<emphasis role="bold">before</emphasis> you power on your notebook. You can also
try whether <ulink url="http://www.brodo.de/cpufreq/">cpufreq</ulink>
(a SpeedStep interface for Linux) helps you.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
The audio/video gets totally out of sync when I run <application>MPlayer</application>
as root on my notebook. It works normal when i run it as a user.
</para></question>
<answer><para>
This is again a power management effect (see above). Plug the external power
connector in <emphasis role="bold">before</emphasis> you power on your notebook
or use the <option>-nortc</option> option.
</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>

<qandaentry>
<question><para>
How can I play MPEG Layer 2 (MP2) audio files?
</para></question>
<answer><para>
You have to use <option>-rawaudio on:format=0x50</option>.
</para></answer>
</qandaentry>
</qandadiv>


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

<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)
    audio_setup: Can't open audio device /dev/dsp: Device or resource busy
    couldn't open/init audio device -> NOSOUND
    Audio: no sound!!!
    Start playing...
</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>
What about the DGA driver? I can't find it!
</para></question>
<answer><para>
<filename>./configure</filename> autodetects your DGA driver. If <option>-vo help</option>
doesn't show DGA, then there's a problem with your X installation. Try
<command>./configure --enable-dga</command> and read the
<link linkend="dga">DGA</link> section. Alternatively, try SDL's DGA driver
with the <option>-vo sdl:dga</option> option.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
OK, <option>-vo help</option> shows DGA driver, but it complains about permissions.
Help me!
</para></question>
<answer><para>
It works only if running as root! It's a DGA limitation. You should become root
(<command>su -</command>), and try again. Another solution is making
<application>MPlayer</application> SUID root, but it's not recommended!
<screen>
     chown root /usr/local/bin/mplayer
     chmod 755 /usr/local/bin/mplayer
     chmod +s /usr/local/bin/mplayer
 </screen>
<warning><para>
This is a <emphasis role="bold">big</emphasis> security risk! <emphasis role="bold">Never</emphasis>
do this on a server or on a computer that you do not control completely because
other users can gain root privileges through SUID root <application>MPlayer</application>.
<emphasis role="bold">You have been warned</emphasis>.
</para></warning>
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
When using XVideo, my Voodoo 3/Banshee says:
<screen>
X Error of failed request: BadAccess (attempt to access private resource denied)
   Major opcode of failed request: 147 (MIT-SHM)
   Minor opcode of failed request: 1 (X_ShmAttach)
   Serial number of failed request: 26
   Current serial number in output stream:27
</screen>
</para></question>
<answer><para>
The <systemitem>tdfx</systemitem> driver in XFree86 4.0.2/4.0.3 had this bug. This was
solved by <ulink url="http://www.xfree86.org/cvs/changes_4_1.html">bug fix #621
of the XFree86 4.1.0 CVS log</ulink>. So upgrade to XFree86 4.1.0 or later.
Alternatively, either download (at least) DRI version 0.6 from the
<ulink url="http://dri.sf.net">DRI homepage</ulink>, or use CVS DRI.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
OpenGL (<option>-vo gl</option>) output doesn't work (hang/black window/X11
errors/...).
</para></question>
<answer><para>
Your OpenGL driver doesn't support dynamic texture changes (glTexSubImage).
It's known not to work with nVidia's binary mess. It's known to work with
Utah-GLX/DRI and Matrox G400 cards. Also with DRI and Radeon cards. It won't
work with DRI and other cards. it will not work with 3DFX cards because of
the 256x256 texture size limit.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I have an nVidia TNT/TNT2 card, and I have a band with strange colors, right
under the movie! Whose fault is this?
</para></question>
<answer><para>
This is a bug of nVidia's binary X driver. These bugs appear ONLY with the
TNT/TNT2 cards, and we can't do anything about it. To fix the problem, upgrade
to the latest nVidia binary driver version. If still bad, complain to nVidia!
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I have an nVidia XYZ card, and when I click on the GUI's display window to
toggle displaying the GUI panel, a black square appears where I clicked. I have
the newest driver.
</para></question>
<answer><para>
Yes, nVidia corrected a previous bug (above), and introduced a new one.
Let's congratulate them. UPDATE: According to <link linkend="nvidia">nVidia</link>,
this has already been fixed.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
Oh the world is cruel ...! SDL has only <systemitem>x11</systemitem> target,
but not <systemitem>xv</systemitem>!
</para></question>
<answer><para>
Try that <systemitem>x11</systemitem> target again. Now try <option>-vo x11
-fs -zoom</option>. See the difference? No?! OK, here comes the enlightenment:
SDL's <systemitem>x11</systemitem> target uses xv when available, you don't have
to worry about it ... Note: With SDL you can force/disable Xv using
<option>-forcexv</option> and <option>-noxv</option>.
</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> does not support DVD menus due to serious
architectural limitations that prevent proper handling of still images and
interactive content. If you want to have fancy menus, you will have to use
another player like <application>xine</application>,
<application>vlc</application> or <application>Ogle</application>.
If you want to see DVD navigation in <application>MPlayer</application> you
will have to implement it yourself, but be aware that it is a major
undertaking.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
While playing a DVD, I encountered this error:
<screen>mplayer: ifo_read.c:1143: ifoRead_C_ADT_internal: Assertion nfo_length / sizeof(cell_adr_t) >= c_adt->nr_of_vobs' failed.</screen>
</para></question>
<answer><para>
This is a known libdvdread 0.9.1/0.9.2 bug. Use <emphasis role="bold">libmpdvdkit2</emphasis>,
which is present in <application>MPlayer</application> source, and used by default.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
Can I compile libdvdread and libdvdcss on my sweet SPARC under Solaris?
</para></question>
<answer><para>
Who knows ... It's said to work, so please test it and send feedback. Refer to
the documentation of libdvdread and its homepage as well. We're not the authors
of libdvdread. Use <emphasis role="bold">libmpdvdkit2</emphasis>, which is present
in <application>MPlayer</application> source, and used by default.
</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>
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>
Where can I get libdvdread and libdvdcss packages?
</para></question>
<answer><para>
You don't need to. Use <emphasis role="bold">libmpdvdkit2</emphasis>, which is
present in the <application>MPlayer</application> source, and used by default.
You can get the mentioned packages from the
<ulink url="http://www.dtek.chalmers.se/groups/dvd/">Ogle site</ulink>.
</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 (described
in the <link linkend="drives">CD chapter</link>).
</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 /path/to/directory
</screen>
</para></answer>
</qandaentry>
</qandadiv>

<qandadiv id="faq-features">
<title>Feature requests</title>
<qandaentry>
<question><para>
If <application>MPlayer</application> is paused and I try to seek or press any key at all,
<application>MPlayer</application> ceases to be paused. I would like to be able
to seek in the paused movie.
</para></question>
<answer><para>
This is very tricky to implement without losing A/V synchronization.
All attempts have failed so far, but patches are welcome.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I'd like to seek +/- 1 frames 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 unlikely to be implemented anytime soon.
</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> or
in the same directory as the file.
</para></answer>
</qandaentry>
</qandadiv>

<qandadiv id="faq-encoding">
<title>Encoding</title>
<qandaentry>
<question><para>
How can I encode?
</para></question>
<answer><para>
Read the <link linkend="mencoder"><application>MEncoder</application></link>
section.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How can I dump a full DVD title to a file?
</para></question>
<answer><para>
Once you selected your title, and made sure it plays fine with
<application>MPlayer</application>, use the option <option>-dumpstream</option>
For example:
<screen>
mplayer -dumpstream dvd://5 -dumpfile <replaceable>dvd_dump.vob</replaceable>
</screen>
will dump the 5th title of the DVD into the file
<replaceable>dvd_dump.vob</replaceable>
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How can I create VCDs?
</para></question>
<answer><para>
Try the <filename>mencvcd</filename> script from the <filename class="directory">TOOLS</filename>
subdirectory. With it you can encode DVDs or other movies to VCD or SVCD format
and even burn them directly to CD.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How can I join two video files?
</para></question>
<answer><para>
MPEG files can be concatenated into a single file with luck.
For AVI files, you can use <application>MEncoder</application>'s
multiple file support like this:
<screen>
mencoder -ovc copy -oac copy -o out.avi file1.avi file2.avi
</screen>
This will only work if the files are of the same resolution and codec.
You can also try
<ulink url="http://fixounet.free.fr/avidemux/">avidemux</ulink> and
<application>avimerge</application> (part of the
<ulink url="http://www.transcoding.org/">transcode</ulink>
tool set).
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How can I fix AVI files with broken index or interleaving?
</para></question>
<answer><para>
Simply copy the video and audio streams into a new file, and
<application>MEncoder</application> generates the index.
Of course this cannot fix possible bugs in the video and/or audio streams.
It also fixes files with broken interleaving, thus the
<option>-ni</option> option will not be needed for them anymore.
<screen>
mencoder -idx <replaceable>input.avi</replaceable> -ovc copy -oac copy -o <replaceable>output.avi</replaceable>
</screen>
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How can I fix the aspect ration of an AVI file?
</para></question>
<answer><para>
You can do such a thing thanks to <application>MEncoder</application>'s
<option>-force-avi-aspect</option> option, which overrides the aspect
stored in the AVI OpenDML vprp header option. For example:
<screen>
mencoder <replaceable>input.avi</replaceable> -ovc copy -oac copy -o <replaceable>output.avi</replaceable> -force-avi-aspect 4/3
</screen>
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I can't encode DVD subtitles into the AVI!
</para></question>
<answer><para>
You have to specify the <option>-sid</option> option correctly!
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How can I encode only selected chapters from a DVD?
</para></question>
<answer><para>
Use the <option>-chapter</option> option correctly, like: <option>-chapter 5-7</option>
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I'm trying to work with 2GB+ files on a VFAT file system. Does it work?
</para></question>
<answer><para>
No, VFAT doesn't support 2GB+ files.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
Why is the recommended bitrate printed by <application>MEncoder</application> negative?
</para></question>
<answer><para>
Because the bitrate you encoded the audio with is too large to fit the
movie on any CD. Check if you have libmp3lame installed properly.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
I can't encode an ASF file to AVI/MPEG-4 (DivX) because it uses 1000 fps.
</para></question>
<answer><para>
Because ASF uses variable frame rate but AVI uses a fixed one, you
have to set it by hand using <option>-ofps</option>.
</para></answer>
</qandaentry>


<qandaentry>
<question><para>
How can I put subtitles in the output file?
</para></question>
<answer><para>
Just pass the <option>-sub &lt;filename&gt;</option> (or <option>-sid</option>,
respectively) option to <application>MEncoder</application>.
</para></answer>
</qandaentry>

<qandaentry>
<question><para>
How do I encode only sound from a music video?
</para></question>
<answer><para>
It's not possible directly, but you can try this (note the
<emphasis role="bold">&amp;</emphasis> at the end of
<command>mplayer</command> command):
<screen>
    mkfifo encode
    mplayer -ao pcm -aofile encode dvd://1 &amp;
    lame <replaceable>your_opts</replaceable> encode music.mp3
    rm encode
</screen>
This allows you to use any encoder, not only <application>LAME</application>,
just replace <command>lame</command> with your favorite audio encoder in the
above command.
</para></answer>
</qandaentry>

</qandadiv>
</qandaset>

</chapter>