<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"><title>4.16. MPEG decoders</title><link rel="stylesheet" type="text/css" href="default.css"><meta name="generator" content="DocBook XSL Stylesheets V1.76.1"><link rel="home" href="index.html" title="MPlayer - The Movie Player"><link rel="up" href="video.html" title="Chapter 4. Video output devices"><link rel="prev" href="dfbmga.html" title="4.15. DirectFB/Matrox (dfbmga)"><link rel="next" href="zr.html" title="4.17. Zr"><link rel="preface" href="howtoread.html" title="How to read this documentation"><link rel="chapter" href="intro.html" title="Chapter 1. Introduction"><link rel="chapter" href="install.html" title="Chapter 2. Installation"><link rel="chapter" href="usage.html" title="Chapter 3. Usage"><link rel="chapter" href="video.html" title="Chapter 4. Video output devices"><link rel="chapter" href="ports.html" title="Chapter 5. Ports"><link rel="chapter" href="mencoder.html" title="Chapter 6. Basic usage of MEncoder"><link rel="chapter" href="encoding-guide.html" title="Chapter 7. Encoding with MEncoder"><link rel="chapter" href="faq.html" title="Chapter 8. Frequently Asked Questions"><link rel="appendix" href="bugreports.html" title="Appendix A. How to report bugs"><link rel="appendix" href="skin.html" title="Appendix B. MPlayer skin format"><link rel="subsection" href="mpeg_decoders.html#dvb" title="4.16.1. DVB output and input"><link rel="subsection" href="mpeg_decoders.html#dxr2" title="4.16.2. DXR2"><link rel="subsection" href="mpeg_decoders.html#dxr3" title="4.16.3. DXR3/Hollywood+"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">4.16. MPEG decoders</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="dfbmga.html">Prev</a> </td><th width="60%" align="center">Chapter 4. Video output devices</th><td width="20%" align="right"> <a accesskey="n" href="zr.html">Next</a></td></tr></table><hr></div><div class="sect1" title="4.16. MPEG decoders"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="mpeg_decoders"></a>4.16. MPEG decoders</h2></div></div></div><div class="sect2" title="4.16.1. DVB output and input"><div class="titlepage"><div><div><h3 class="title"><a name="dvb"></a>4.16.1. DVB output and input</h3></div></div></div><p>
<span class="application">MPlayer</span> supports cards with the Siemens DVB chipset
from vendors like Siemens, Technotrend, Galaxis or Hauppauge. The latest DVB
drivers are available from the
<a class="ulink" href="http://www.linuxtv.org" target="_top">Linux TV site</a>.
If you want to do software transcoding you should have at least a 1GHz CPU.
</p><p>
Configure should detect your DVB card. If it did not, force detection with
</p><pre class="screen">./configure --enable-dvb</pre><p>
Then compile and install as usual.</p><p title="USAGE"><b>USAGE. </b>
Hardware decoding of streams containing MPEG-1/2 video and/or MPEG audio can be done with this
command:
</p><pre class="screen">
mplayer -ao mpegpes -vo mpegpes <em class="replaceable"><code>file.mpg|vob</code></em>
</pre><p title="USAGE">
</p><p>
Decoding of any other type of video stream requires transcoding to MPEG-1, thus it's slow
and may not be worth the trouble, especially if your computer is slow.
It can be achieved using a command like this:
</p><pre class="screen">
mplayer -ao mpegpes -vo mpegpes <em class="replaceable"><code>yourfile.ext</code></em>
mplayer -ao mpegpes -vo mpegpes -vf expand <em class="replaceable"><code>yourfile.ext</code></em>
</pre><p>
Note that DVB cards only support heights 288 and 576 for PAL or 240 and 480 for
NTSC. You <span class="bold"><strong>must</strong></span> rescale for other heights by
adding <tt class="option">scale=width:height</tt> with the width and height you want
to the <tt class="option">-vf</tt> option. DVB cards accept various widths, like 720,
704, 640, 512, 480, 352 etc. and do hardware scaling in horizontal direction,
so you do not need to scale horizontally in most cases.
For a 512x384 (aspect 4:3) MPEG-4 (DivX) try:
</p><pre class="screen">mplayer -ao mpegpes -vo mpegpes -vf scale=512:576</pre><p>
</p><p>
If you have a widescreen movie and you do not want to scale it to full height,
you can use the <tt class="option">expand=w:h</tt> filter to add black bands. To view a
640x384 MPEG-4 (DivX), try:
</p><pre class="screen">
mplayer -ao mpegpes -vo mpegpes -vf expand=640:576 <em class="replaceable"><code>file.avi</code></em>
</pre><p>
</p><p>
If your CPU is too slow for a full size 720x576 MPEG-4 (DivX), try downscaling:
</p><pre class="screen">
mplayer -ao mpegpes -vo mpegpes -vf scale=352:576 <em class="replaceable"><code>file.avi</code></em>
</pre><p>
</p><p>If speed does not improve, try vertical downscaling, too:
</p><pre class="screen">
mplayer -ao mpegpes -vo mpegpes -vf scale=352:288 <em class="replaceable"><code>file.avi</code></em>
</pre><p>
</p><p>
For OSD and subtitles use the OSD feature of the expand filter. So, instead of
<tt class="option">expand=w:h</tt> or <tt class="option">expand=w:h:x:y</tt>, use
<tt class="option">expand=w:h:x:y:1</tt> (the 5th parameter <tt class="option">:1</tt>
at the end will enable OSD rendering). You may want to move the image up a bit
to get a bigger black zone for subtitles. You may also want to move subtitles
up, if they are outside your TV screen, use the
<tt class="option">-subpos <0-100></tt>
option to adjust this (<tt class="option">-subpos 80</tt> is a good choice).
</p><p>
In order to play non-25fps movies on a PAL TV or with a slow CPU, add the
<tt class="option">-framedrop</tt> option.
</p><p>
To keep the aspect ratio of MPEG-4 (DivX) files and get the optimal scaling
parameters (hardware horizontal scaling and software vertical scaling
while keeping the right aspect ratio), use the new dvbscale filter:
</p><pre class="screen">
for a 4:3 TV: -vf dvbscale,scale=-1:0,expand=-1:576:-1:-1:1
for a 16:9 TV: -vf dvbscale=1024,scale=-1:0,expand=-1:576:-1:-1:1
</pre><p>
</p><p title="Digital TV (DVB input module)"><b>Digital TV (DVB input module). </b>You can use your DVB card for watching Digital TV.</p><p>
You should have the programs <span class="command"><strong>scan</strong></span> and
<span class="command"><strong>szap/tzap/czap/azap</strong></span> installed; they are all included in
the drivers package.
</p><p>
Verify that your drivers are working properly with a program such as
<a class="ulink" href="http://sf.net/projects/dvbtools/" target="_top"><span class="command"><strong>dvbstream</strong></span></a>
(that is the base of the DVB input module).
</p><p>
Now you should compile a <tt class="filename">~/.mplayer/channels.conf</tt>
file, with the syntax accepted by <span class="command"><strong>szap/tzap/czap/azap</strong></span>, or
have <span class="command"><strong>scan</strong></span> compile it for you.
</p><p>
If you have more than one card type (e.g. Satellite, Terrestrial, Cable and ATSC)
you can save your channels files as
<tt class="filename">~/.mplayer/channels.conf.sat</tt>,
<tt class="filename">~/.mplayer/channels.conf.ter</tt>,
<tt class="filename">~/.mplayer/channels.conf.cbl</tt>,
and <tt class="filename">~/.mplayer/channels.conf.atsc</tt>,
respectively, so as to implicitly hint <span class="application">MPlayer</span>
to use these files rather than <tt class="filename">~/.mplayer/channels.conf</tt>,
and you only need to specify which card to use.
</p><p>
Make sure that you have <span class="emphasis"><em>only</em></span> Free to Air
channels in your <tt class="filename">channels.conf</tt> file, or
<span class="application">MPlayer</span> will wait for an unencrypted transmission.
</p><p>
In your audio and video fields you can use an extended syntax:
<tt class="option">...:pid[+pid]:...</tt> (for a maximum of 6 pids each);
in this case <span class="application">MPlayer</span> will include in the
stream all the indicated pids, plus pid 0 (that contains the PAT).
You should always include in each row the PMT and PCR pids for the
corresponding channel (if you know them).
You can also specify 8192, this will select all pids on this frequency
and you can then switch between the programs with TAB.
This might need more bandwidth, though cheap cards always transfer all
channels at least to the kernel so it does not make much of a difference
for these.
Other possible uses are: televideo pid, second audio track, etc.
</p><p>
If <span class="application">MPlayer</span> complains frequently about
</p><pre class="screen">Too many video/audio packets in the buffer</pre><p> or
if you notice a growing desynchronization between audio and
video verify the presence of the PCR pid in your stream
(needed to comply with the buffering model of the transmitter)
and/or try to use the libavformat MPEG-TS demuxer by adding
<tt class="option">-demuxer lavf -lavfdopts probesize=128</tt>
to your command line.
</p><p>
To show the first of the channels present in your list, run
</p><pre class="screen">mplayer dvb://</pre><p>
</p><p>
If you want to watch a specific channel, such as R1, run
</p><pre class="screen">mplayer dvb://<em class="replaceable"><code>R1</code></em></pre><p>
</p><p>
If you have more than one card you also need to specify the number of the card
where the channel is visible (e.g. 2) with the syntax:
</p><pre class="screen">mplayer dvb://<em class="replaceable"><code>2@R1</code></em></pre><p>
</p><p>
To change channels press the <span class="keycap"><b>h</b></span> (next) and
<span class="keycap"><b>k</b></span> (previous) keys, or use the
<a class="link" href="fonts-osd.html#osdmenu" title="2.4.3. OSD menu">OSD menu</a>.
</p><p>
To temporarily disable the audio or the video stream copy the
following to <tt class="filename">~/.mplayer/input.conf</tt>:
</p><pre class="screen">
% set_property switch_video -2
& step_property switch_video
? set_property switch_audio -2
^ step_property switch_audio
</pre><p>
(Overriding the action keys as preferred.) When pressing the key
corresponding to switch_x -2 the associated stream will be closed;
when pressing the key corresponding to step_x the stream will be reopened.
Notice that this switching mechanism will not work as expected when there
are multiple audio and video streams in the multiplex.
</p><p>
During playback (not during recording), in order to prevent stuttering
and error messages such as 'Your system is too slow' it is advisable to add
</p><pre class="screen">
-mc 10 -speed 0.97 -af scaletempo
</pre><p>
to your command line, adjusting the scaletempo parameters as preferred.
</p><p>
If your <tt class="filename">~/.mplayer/menu.conf</tt> contains a
<code class="literal"><dvbsel></code> entry, such as the one in the example
file <tt class="filename">etc/dvb-menu.conf</tt> (that you can use to overwrite
<tt class="filename">~/.mplayer/menu.conf</tt>), the main menu will show a
sub-menu entry that will permit you to choose one of the channels present
in your <tt class="filename">channels.conf</tt>, possibly preceded by a menu
with the list of cards available if more than one is usable by
<span class="application">MPlayer</span>.
</p><p>
If you want to save a program to disk you can use
</p><pre class="screen">
mplayer -dumpfile <em class="replaceable"><code>r1.ts</code></em> -dumpstream dvb://<em class="replaceable"><code>R1</code></em>
</pre><p>
</p><p>
If you want to record it in a different format (re-encoding it) instead
you can run a command such as
</p><pre class="screen">
mencoder -o <em class="replaceable"><code>r1.avi</code></em> -ovc xvid -xvidencopts bitrate=800 \
-oac mp3lame -lameopts cbr:br=128 -pp=ci dvb://<em class="replaceable"><code>R1</code></em>
</pre><p>
</p><p>
Read the man page for a list of options that you can pass to the
DVB input module.
</p><p title="FUTURE"><b>FUTURE. </b>
If you have questions or want to hear feature announcements and take part in
discussions on this subject, join our
<a class="ulink" href="http://lists.mplayerhq.hu/mailman/listinfo/mplayer-dvb" target="_top">MPlayer-DVB</a>
mailing list. Please remember that the list language is English.
</p><p>
In the future you may expect the ability to display OSD and subtitles using
the native OSD feature of DVB cards.
</p></div><div class="sect2" title="4.16.2. DXR2"><div class="titlepage"><div><div><h3 class="title"><a name="dxr2"></a>4.16.2. DXR2</h3></div></div></div><p>
<span class="application">MPlayer</span> supports hardware accelerated playback
with the Creative DXR2 card.
</p><p>
First of all you will need properly installed DXR2 drivers. You can find
the drivers and installation instructions at the
<a class="ulink" href="http://dxr2.sf.net/" target="_top">DXR2 Resource Center</a> site.
</p><div class="variablelist" title="USAGE"><p class="title"><b>USAGE</b></p><dl><dt><span class="term"><tt class="option">-vo dxr2</tt></span></dt><dd><p>Enable TV output.</p></dd><dt><span class="term"><tt class="option">-vo dxr2:x11</tt> or <tt class="option">-vo dxr2:xv</tt></span></dt><dd><p>Enable Overlay output in X11.</p></dd><dt><span class="term"><tt class="option">-dxr2 <option1:option2:...></tt></span></dt><dd><p>
This option is used to control the DXR2 driver.
</p></dd></dl></div><p>
The overlay chipset used on the DXR2 is of pretty bad quality but the
default settings should work for everybody. The OSD may be usable with the
overlay (not on TV) by drawing it in the colorkey. With the default colorkey
settings you may get variable results, usually you will see the colorkey
around the characters or some other funny effect. But if you properly adjust
the colorkey settings you should be able to get acceptable results.
</p><p>Please see the man page for available options.</p></div><div class="sect2" title="4.16.3. DXR3/Hollywood+"><div class="titlepage"><div><div><h3 class="title"><a name="dxr3"></a>4.16.3. DXR3/Hollywood+</h3></div></div></div><p>
<span class="application">MPlayer</span> supports hardware accelerated playback
with the Creative DXR3 and Sigma Designs Hollywood Plus cards. These cards
both use the em8300 MPEG decoder chip from Sigma Designs.
</p><p>
First of all you will need properly installed DXR3/H+ drivers, version 0.12.0
or later. You can find the drivers and installation instructions at the
<a class="ulink" href="http://dxr3.sf.net/" target="_top">DXR3 & Hollywood Plus for Linux</a>
site. <tt class="filename">configure</tt> should detect your card automatically,
compilation should go without problems.
</p><div class="variablelist" title="USAGE"><p class="title"><b>USAGE</b></p><dl><dt><span class="term"><tt class="option">-vo dxr3:prebuf:sync:norm=x:<em class="replaceable"><code>device</code></em></tt></span></dt><dd><p>
<tt class="option">overlay</tt> activates the overlay instead of TV-out. It requires
that you have a properly configured overlay setup to work right. The easiest
way to configure the overlay is to first run autocal. Then run mplayer with
dxr3 output and without overlay turned on, run dxr3view. In dxr3view you can
tweak the overlay settings and see the effects in realtime, perhaps this feature
will be supported by the <span class="application">MPlayer</span> GUI in the future.
When overlay is properly set up you will no longer need to use dxr3view.
<tt class="option">prebuf</tt> turns on prebuffering. Prebuffering is a feature of the
em8300 chip that enables it to hold more than one frame of video at a time.
This means that when you are running with prebuffering
<span class="application">MPlayer</span> will try to keep the video buffer filled
with data at all times.
If you are on a slow machine <span class="application">MPlayer</span> will probably
use close to, or precisely 100% of CPU.
This is especially common if you play pure MPEG streams
(like DVDs, SVCDs a.s.o.) since <span class="application">MPlayer</span> will not have
to reencode it to MPEG it will fill the buffer very fast.
With prebuffering video playback is <span class="bold"><strong>much</strong></span>
less sensitive to other programs hogging the CPU, it will not drop frames unless
applications hog the CPU for a long time.
When running without prebuffering the em8300 is much more sensitive to CPU load,
so it is highly suggested that you turn on <span class="application">MPlayer</span>'s
<tt class="option">-framedrop</tt> option to avoid further loss of sync.
<tt class="option">sync</tt> will turn on the new sync-engine. This is currently an
experimental feature. With the sync feature turned on the em8300's internal
clock will be monitored at all times, if it starts to deviate from
<span class="application">MPlayer</span>'s clock it will be reset causing the em8300
to drop any frames that are lagging behind.
<tt class="option">norm=x</tt> will set the TV norm of the DXR3 card without the need
for external tools like em8300setup. Valid norms are 5 = NTSC, 4 = PAL-60,
3 = PAL. Special norms are 2 (auto-adjust using PAL/PAL-60) and 1 (auto-adjust
using PAL/NTSC) because they decide which norm to use by looking at the frame
rate of the movie. norm = 0 (default) does not change the current norm.
<tt class="option"><em class="replaceable"><code>device</code></em></tt> = device number to use if
you have more than one em8300 card. Any of these options may be left out.
<tt class="option">:prebuf:sync</tt> seems to work great when playing MPEG-4 (DivX)
movies. People have reported problems using the prebuf option when playing
MPEG-1/2 files.
You might want to try running without any options first, if you have sync
problems, or DVD subtitle problems, give <tt class="option">:sync</tt> a try.
</p></dd><dt><span class="term"><tt class="option">-ao oss:/dev/em8300_ma-<em class="replaceable"><code>X</code></em></tt></span></dt><dd><p>
For audio output, where <em class="replaceable"><code>X</code></em> is the device number
(0 if one card).
</p></dd><dt><span class="term"><tt class="option">-af resample=<em class="replaceable"><code>xxxxx</code></em></tt></span></dt><dd><p>
The em8300 cannot play back samplerates lower than 44100Hz. If the sample
rate is below 44100Hz select either 44100Hz or 48000Hz depending on which
one matches closest. I.e. if the movie uses 22050Hz use 44100Hz as
44100 / 2 = 22050, if it is 24000Hz use 48000Hz as 48000 / 2 = 24000
and so on.
This does not work with digital audio output (<tt class="option">-ac hwac3</tt>).
</p></dd><dt><span class="term"><tt class="option">-vf lavc</tt></span></dt><dd><p>
To watch non-MPEG content on the em8300 (i.e. MPEG-4 (DivX) or RealVideo)
you have to specify an MPEG-1 video filter such as
<code class="systemitem">libavcodec</code> (lavc).
See the man page for further info about <tt class="option">-vf lavc</tt>.
Currently there is no way of setting the fps of the em8300 which means that
it is fixed to 30000/1001 fps.
Because of this it is highly recommended that you use
<tt class="option">-vf lavc=<em class="replaceable"><code>quality</code></em>:25</tt>
especially if you are using prebuffering. Then why 25 and not 30000/1001?
Well, the thing is that when you use 30000/1001 the picture becomes a bit
jumpy.
The reason for this is unknown to us.
If you set it to somewhere between 25 and 27 the picture becomes stable.
For now all we can do is accept this for a fact.
</p></dd><dt><span class="term"><tt class="option">-vf expand=-1:-1:-1:-1:1</tt></span></dt><dd><p>
Although the DXR3 driver can put some OSD onto the MPEG-1/2/4 video, it has
much lower quality than <span class="application">MPlayer</span>'s traditional OSD,
and has several refresh problems as well. The command line above will firstly
convert the input video to MPEG-4 (this is mandatory, sorry), then apply an
expand filter which won't expand anything (-1: default), but apply the normal
OSD onto the picture (that's what the "1" at the end does).
</p></dd><dt><span class="term"><tt class="option">-ac hwac3</tt></span></dt><dd><p>
The em8300 supports playing back AC-3 audio (surround sound) through the
digital audio output of the card. See the <tt class="option">-ao oss</tt> option
above, it must be used to specify the DXR3's output instead of a sound card.
</p></dd></dl></div></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="dfbmga.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="video.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="zr.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">4.15. DirectFB/Matrox (dfbmga) </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> 4.17. Zr</td></tr></table></div></body></html>
