mirror of https://github.com/mpv-player/mpv
284 lines
13 KiB
HTML
284 lines
13 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
|
|
<HTML>
|
|
|
|
<HEAD>
|
|
<TITLE>Sound - MPlayer - The Movie Player for Linux</TITLE>
|
|
<LINK REL="stylesheet" TYPE="text/css" HREF="default.css">
|
|
<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1">
|
|
</HEAD>
|
|
|
|
<BODY>
|
|
|
|
|
|
<H3><A NAME="audio">2.3.2 Audio output devices</A></H3>
|
|
|
|
<P><B>MPlayer</B>'s audio interface is called <I>libao2</I>. It currently
|
|
contains these drivers:</P>
|
|
|
|
<TABLE BORDER=0>
|
|
<TR><TD COLSPAN=4><P><B>General:</B></P></TD></TR>
|
|
<TR><TD> </TD><TD VALIGN=top>oss</TD><TD> </TD><TD>OSS (ioctl) driver (supports hardware AC3 passthrough)</TD></TR>
|
|
<TR><TD></TD><TD VALIGN=top>sdl</TD><TD></TD><TD>SDL driver (supports up/downsampling, <B>ESD</B>, <B>ARTS</B> etc)</TD></TR>
|
|
<TR><TD></TD><TD VALIGN=top>nas</TD><TD></TD><TD>NAS (Network Audio System) driver</TD></TR>
|
|
<TR><TD></TD><TD VALIGN=top>alsa5</TD><TD></TD><TD>native ALSA 0.5 driver</TD></TR>
|
|
<TR><TD></TD><TD VALIGN=top>alsa9</TD><TD></TD><TD>native ALSA 0.9 driver (supports hardware AC3 passthrough)</TD></TR>
|
|
<TR><TD></TD><TD VALIGN=top>sun</TD><TD></TD><TD>SUN audio driver (<CODE>/dev/audio</CODE>) for BSD and Solaris8 users</TD></TR>
|
|
<TR><TD></TD><TD VALIGN=top>arts</TD><TD></TD><TD>native ARTS driver (mostly for KDE users)</TD></TR>
|
|
</TABLE>
|
|
|
|
<P>Fact is, Linux sound card drivers have compatibility problems.
|
|
It <B>may</B> take a while to find your optimal settings.</P>
|
|
|
|
<UL>
|
|
<LI>If you have an OSS driver, first try <CODE>-ao oss</CODE> (this is the
|
|
default). If you experience glitches, halts or anything out of the
|
|
ordinary, try <CODE>-ao sdl</CODE> (NOTE: you need to have SDL libraries
|
|
and header files installed). The SDL audio driver helps in a lot of cases
|
|
and also supports ESD, ARTS, and up/downsampling. (ESD is the sound daemon
|
|
from GNOME, ARTS is from KDE.)</LI>
|
|
<LI>If you have ALSA version 0.5, then you almost always have to use
|
|
<CODE>-ao alsa5</CODE> , since ALSA 0.5 has buggy OSS emulation code, and
|
|
will <B>crash MPlayer</B> with a message like this:<BR>
|
|
<CODE>DEMUXER: Too many (945 in 8390980 bytes) video packets in the buffer!</CODE></LI>
|
|
<LI>If you have ALSA version 0.9 you may choose between <CODE>-ao oss</CODE>
|
|
and <CODE>-ao sdl</CODE>. You can also use <CODE>-ao alsa9</CODE>. It
|
|
works, but there may be problems like lost sync and disappearing
|
|
audio.</LI>
|
|
</UL>
|
|
|
|
<P>On <B>Solaris/FreeBSD</B> systems, use the SUN audio driver with the
|
|
<CODE>-ao sun</CODE> option, otherwise neither video nor audio will work.</P>
|
|
|
|
|
|
<H4><A NAME="experiences">2.3.2.1 Sound Card experiences, recommendations</A></H4>
|
|
|
|
<TABLE BORDER=0 WIDTH="100%">
|
|
<TR><TD COLSPAN=3><B>VIA onboard chipset (via82cxxx) 48kHz only</B></TD></TR>
|
|
<TR><TD></TD><TD>Driver:</TD><TD> from <A HREF="http://sourceforge.net/project/showfiles.php?group_id=3242&release_id=59602">sourceforge.net</A></TD></TR>
|
|
|
|
<TR><TD COLSPAN=3><B>Aureal Vortex 2</B></TD></TR>
|
|
<TR><TD> </TD><TD>OSS:</TD><TD>no driver</TD></TR>
|
|
<TR><TD></TD><TD>OSS/Pro:</TD><TD>OK</TD></TR>
|
|
<TR><TD></TD><TD>ALSA:</TD><TD>no driver</TD></TR>
|
|
<TR><TD></TD><TD>Max kHz:</TD><TD>48</TD></TR>
|
|
<TR><TD></TD><TD>Driver:</TD><TD><A HREF="http://aureal.sourceforge.net">aureal.sourceforge.net</A></TD></TR>
|
|
<TR><TD></TD><TD>Driver2:</TD><TD> from <A HREF="http://makacs.poliod.hu/~pontscho/aureal/au88xx-1.1.3.tar.bz2">Pontscho's page</A><BR>
|
|
(<I>buffer size increased to 32k</I>)</TD></TR>
|
|
|
|
<TR><TD COLSPAN=3><B>GUS PnP</B></TD></TR>
|
|
<TR><TD></TD><TD>OSS:</TD><TD>no driver</TD></TR>
|
|
<TR><TD></TD><TD>OSS/Pro:</TD><TD>OK</TD></TR>
|
|
<TR><TD></TD><TD>ALSA:</TD><TD>OK</TD></TR>
|
|
<TR><TD></TD><TD>Max kHz:</TD><TD>48</TD></TR>
|
|
|
|
<TR><TD COLSPAN=3><B>SB Live!</B></TD></TR>
|
|
<TR><TD></TD><TD>OSS:</TD><TD>Analog OK, SP/DIF not working</TD></TR>
|
|
<TR><TD></TD><TD>ALSA:</TD><TD>Both OK</TD></TR>
|
|
<TR><TD></TD><TD>Max kHz:</TD><TD>192</TD></TR>
|
|
|
|
<TR><TD COLSPAN=3><B>SB AWE 64</B></TD></TR>
|
|
<TR><TD></TD><TD>OSS:</TD><TD>max 44kHz</TD></TR>
|
|
<TR><TD></TD><TD>ALSA:</TD><TD>48kHz sounds bad</TD></TR>
|
|
<TR><TD></TD><TD>Max kHz:</TD><TD>48</TD></TR>
|
|
|
|
<TR><TD COLSPAN=3><B>Gravis UltraSound ACE</B></TD></TR>
|
|
<TR><TD></TD><TD>OSS:</TD><TD>not OK</TD></TR>
|
|
<TR><TD></TD><TD>ALSA:</TD><TD>OK</TD></TR>
|
|
<TR><TD></TD><TD>Max kHz:</TD><TD>44</TD></TR>
|
|
|
|
<TR><TD COLSPAN=3><B>Gravis UltraSound MAX</B></TD></TR>
|
|
<TR><TD></TD><TD>OSS:</TD><TD>OK</TD></TR>
|
|
<TR><TD></TD><TD>ALSA:</TD><TD>OK (?)</TD></TR>
|
|
<TR><TD></TD><TD>Max kHz:</TD><TD>48</TD></TR>
|
|
|
|
<TR><TD COLSPAN=3><B>ESS 688</B></TD></TR>
|
|
<TR><TD></TD><TD>OSS:</TD><TD>OK</TD></TR>
|
|
<TR><TD></TD><TD>ALSA:</TD><TD>OK (?)</TD></TR>
|
|
<TR><TD></TD><TD>Max kHz:</TD><TD>48</TD></TR>
|
|
|
|
<TR><TD COLSPAN=3><B>C-Media cards (which ones?)</B></TD></TR>
|
|
<TR><TD></TD><TD>OSS:</TD><TD>not OK (hissing) (?)</TD></TR>
|
|
<TR><TD></TD><TD>ALSA:</TD><TD>OK (?)</TD></TR>
|
|
<TR><TD></TD><TD>Max kHz:</TD><TD>?</TD></TR>
|
|
|
|
<TR><TD COLSPAN=3><B>Yamaha cards (*ymf*)</B></TD></TR>
|
|
<TR><TD></TD><TD>OSS:</TD><TD>not OK (?) (maybe <CODE>-ao sdl</CODE>)</TD></TR>
|
|
<TR><TD></TD><TD>ALSA:</TD><TD>OK only with ALSA 0.5 with OSS emulation <B>AND</B> <CODE>-ao sdl</CODE> (!) (?)</TD></TR>
|
|
<TR><TD></TD><TD>Max kHz:</TD><TD>?</TD></TR>
|
|
|
|
<TR><TD COLSPAN=3><B>Cards with envy24 chips (like Terratec EWS88MT)</B></TD></TR>
|
|
<TR><TD></TD><TD>OSS:</TD><TD>?</TD></TR>
|
|
<TR><TD></TD><TD>OSS/Pro:</TD><TD>OK</TD></TR>
|
|
<TR><TD></TD><TD>ALSA:</TD><TD>?</TD></TR>
|
|
<TR><TD></TD><TD>Max kHz:</TD><TD>?</TD></TR>
|
|
|
|
<TR><TD COLSPAN=3><B>PC Speaker or DAC</B></TD></TR>
|
|
<TR><TD></TD><TD>OSS:</TD><TD>OK (Use the SDL driver: <CODE>-ao sdl</CODE>)</TD></TR>
|
|
<TR><TD></TD><TD>ALSA:</TD><TD>no driver</TD></TR>
|
|
<TR><TD></TD><TD>Max kHz:</TD><TD>The driver emulates 44.1, maybe more.</TD></TR>
|
|
<TR><TD></TD><TD>Driver:</TD><TD><A HREF="ftp://ftp.infradead.org/pub/pcsp">ftp://ftp.infradead.org/pub/pcsp</A></TD></TR>
|
|
</TABLE>
|
|
|
|
<P>On Linux, a 2.4.x kernel is highly recommended. Kernel 2.2 is not tested.</P>
|
|
|
|
<P>If sound clicks when playing from CD-ROM, turn on IRQ unmasking, e.g.
|
|
<CODE>hdparm -u1 /dev/cdrom</CODE> (<CODE>man hdparm</CODE>). This is
|
|
generally beneficial and described more detailed in the <A
|
|
HREF="cd-dvd.html#drives">CD-ROM section</A>.</P>
|
|
|
|
<P>Sharing your sound card with another application like XMMS is <B>strongly
|
|
discouraged</B>! If the other sound application is using ESD, start
|
|
<B>MPlayer</B> with the <CODE>-vo sdl:esd</CODE> option to combine both
|
|
sound streams. In fact, the option <CODE>-vo sdl:esd</CODE> could be used
|
|
with ESD even when playing <B>Mplayer</B> alone.</P>
|
|
|
|
<P>Feedback to this document is welcome. Please tell us how <B>MPlayer</B>
|
|
and your sound card(s) worked together.</P>
|
|
|
|
|
|
<H4><A NAME="plugins">2.3.2.2 Audio plugins</A></H4>
|
|
|
|
<P><B>MPlayer</B> has support for audio plugins. Audio plugins can be used for
|
|
changing the properties of the audio data before the sound reaches the sound
|
|
card. They are enabled using the <CODE>-aop</CODE> switch which takes a
|
|
<CODE>list=plugin1,plugin2,...</CODE> argument. The <CODE>list</CODE> argument
|
|
is required and determines which plugins should be used and in which order they
|
|
should be executed. Example:</P>
|
|
|
|
<P> <CODE>mplayer media.avi -aop list=resample,format</CODE></P>
|
|
|
|
<P>would run the sound through the resampling plugin followed by the format
|
|
plugin.</P>
|
|
|
|
<P>The plugins can also have switches that change their behavior. These
|
|
switches are explained in detail in the sections below. A plugin will execute
|
|
using default settings if its switches are omitted. Here is an example of how
|
|
to use plugins in combination with plugin specific switches:</P>
|
|
|
|
<P> <CODE>mplayer media.avi -aop
|
|
list=resample,format:fout=44100:format=0x8</CODE></P>
|
|
|
|
<P>would set the output frequency of the resample plugin to 44100Hz and the
|
|
output format of the format plugin to AFMT_U8.</P>
|
|
|
|
<P>Currently audio plugins can not be used in <B>MEncoder</B>.</P>
|
|
|
|
|
|
<H5><A NAME="resample">2.3.2.2.1 Up/Downsampling</A></H5>
|
|
|
|
<P><B>MPlayer</B> fully supports up/downsampling of the sound. This plugin can
|
|
be used if you have a fixed frequency sound card or if you are
|
|
stuck with an old sound card that is only capable of max 44.1kHz.
|
|
Limitations in your hardware are not auto detected, so you have to specify
|
|
the sample frequency explicitly. This plugin has one switch:
|
|
<CODE>fout</CODE> which is used for setting the desired output sample
|
|
frequency. It defaults to 48kHz, and is given in
|
|
<Hz>.</P>
|
|
|
|
<P>Usage:<BR>
|
|
<CODE>mplayer media.avi -aop list=resample:fout=<required
|
|
frequency in Hz, like 44100></CODE></P>
|
|
|
|
<P>Note that the output frequency should not be scaled up from the default value.
|
|
Scaling up will cause the audio and video streams to be played in slow motion
|
|
in addition to audio distortion.</P>
|
|
|
|
|
|
<H5><A NAME="surround_decoding">2.3.2.2.2 Surround Sound decoding</A></H5>
|
|
|
|
<P><B>MPlayer</B> has an audio plugin that can decode matrix encoded
|
|
surround sound. Dolby Surround is an example of a matrix encoded format.
|
|
Many files with 2 channel audio actually contain matrixed surround sound.
|
|
To use this feature you need a sound card supporting at least 4 channels.</P>
|
|
|
|
<P>Usage:<BR>
|
|
<CODE>mplayer media.avi -aop list=surround</CODE></P>
|
|
|
|
|
|
<H5><A NAME="format">2.3.2.2.3 Sample format converter</A></H5>
|
|
|
|
<P>If your sound card driver does not support signed 16bit <CODE>int</CODE> data type,
|
|
this plugin can
|
|
be used to change the format to one which your sound card can understand. It
|
|
has one switch, <CODE>format</CODE>, which can be set to one of the numbers
|
|
found in <CODE>libao2/afmt.h</CODE>. This plugin is hardly ever needed and is
|
|
intended for advanced users. Keep in mind that this plugin only changes the
|
|
sample format and not the sample frequency or the number of channels.</P>
|
|
|
|
<P>Usage:<BR>
|
|
<CODE>mplayer media.avi -aop
|
|
list=format:format=<required output format></CODE></P>
|
|
|
|
|
|
<H5><A NAME="delay">2.3.2.2.4 Delay</A></H5>
|
|
|
|
<P>This plugin delays the sound and is intended as an example of how to develop
|
|
new plugins. It can not be used for anything useful from a users perspective
|
|
and is mentioned here for the sake of completeness only. Do not use this
|
|
plugin unless you are a developer.</P>
|
|
|
|
|
|
<H5><A NAME="volume">2.3.2.2.5 Software volume control</A></H5>
|
|
|
|
<P>This plugin is a software replacement for the volume control, and
|
|
can be used on machines with a broken mixer device. It can also be
|
|
used if one wants to change the output volume of <B>MPlayer</B>
|
|
without changing the PCM volume setting in the mixer. It has one
|
|
switch <CODE>volume</CODE> that is used for setting the initial
|
|
sound level. The initial sound level can be set to values between 0
|
|
and 255 and defaults to 101 which equals 0dB amplification. Use this
|
|
plugin with caution since it can reduce the signal to noise ratio of
|
|
the sound. In most cases it is best to set the level for the PCM
|
|
sound to max, leave this plugin out and control the output level to
|
|
your speakers with the master volume control of the mixer. If there is an
|
|
external amplifier connected to the computer (this is almost always
|
|
the case), the noise level can be minimized by adjusting the master
|
|
level and the volume knob on the amplifier until the hissing noise
|
|
in the background is gone.</P>
|
|
|
|
<P>Usage:<BR>
|
|
<CODE>mplayer media.avi -aop
|
|
list=volume:volume=<0-255></CODE></P>
|
|
|
|
<P>This plugin also has compressor or "soft-clipping" capabilities.
|
|
Compression can be used if the dynamic range of the sound is very
|
|
high or if the dynamic range of the loudspeakers is very
|
|
low. Be aware that this feature creates distortion and should be
|
|
considered a last resort.</P>
|
|
|
|
<P>Usage:<BR>
|
|
<CODE>mplayer media.avi -aop
|
|
list=volume:softclip</CODE></P>
|
|
|
|
|
|
<H5><A NAME="extrastereo">2.3.2.2.6 Extrastereo</A></H5>
|
|
|
|
<P>This plugin (linearly) increases the difference between left and right
|
|
channels (like the XMMS extrastereo plugin) which gives some sort of "live"
|
|
effect to playback.</P>
|
|
|
|
<P>Usage:<BR>
|
|
<CODE>mplayer media.avi -aop list=extrastereo</CODE><BR>
|
|
<CODE>mplayer media.avi -aop list=extrastereo:mul=3.45</CODE></P>
|
|
|
|
<P>The default coefficient (<CODE>mul</CODE>) is a float number that defaults
|
|
to 2.5. If you set it to 0.0, you will have mono sound (average of both
|
|
channels). If you set it to 1.0, sound will be unchanged, if you set it to
|
|
-1.0, left and right channels will be swapped.</P>
|
|
|
|
|
|
<H5><A NAME="normalizer">2.3.2.2.7 Volume normalizer</A></H5>
|
|
|
|
<P>This plugin maximizes the volume without distorting the sound.</P>
|
|
|
|
<P>Usage:<BR>
|
|
<CODE>mplayer media.avi -aop list=volnorm</CODE><BR>
|
|
|
|
|
|
<H5><A NAME="surround">2.3.2.2.8 Surround</A></H5>
|
|
|
|
<P>Someone should document something, sometime.</P>
|
|
|
|
</BODY>
|
|
</HTML>
|