mirror of
https://github.com/mpv-player/mpv
synced 2025-01-02 21:12:23 +00:00
bandaid build fix
git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@15352 b3059339-0415-0410-9bf9-f77b7e298cf2
This commit is contained in:
parent
cafaabbf54
commit
64e88c0501
@ -547,6 +547,149 @@ Apple,
|
||||
<step><para>ÓËÏÍÐÉÌÉÒÕÊÔÅ <application>MPlayer</application></para></step>
|
||||
</procedure>
|
||||
|
||||
</sect3>
|
||||
|
||||
<sect3 id="codec-x264">
|
||||
<title>x264</title>
|
||||
|
||||
<sect4 id="codec-x264-whatis">
|
||||
<title>What is x264?</title>
|
||||
<para>
|
||||
<systemitem class="library">x264</systemitem> is a library for
|
||||
creating H.264 video streams.
|
||||
It is not 100% complete, but currently it has at least some kind
|
||||
of support for most of the H.264 features which impact quality.
|
||||
There are also many advanced features in the H.264 specification
|
||||
which have nothing to do with video quality per se; many of these
|
||||
are not yet implemented in
|
||||
<systemitem class="library">x264</systemitem>.
|
||||
</para>
|
||||
|
||||
<itemizedlist>
|
||||
<title>Encoder features</title>
|
||||
<listitem><para>CAVLC/CABAC</para></listitem>
|
||||
<listitem><para>Multi-references</para></listitem>
|
||||
<listitem><para>Intra: all macroblock types (16x16 and 4x4 with
|
||||
all predictions)</para></listitem>
|
||||
<listitem><para>Inter P: all partitions (from 16x16 down to
|
||||
4x4)</para></listitem>
|
||||
<listitem><para>Inter B: partitions from 16x16 down to 8x8
|
||||
(including SKIP/DIRECT)</para></listitem>
|
||||
<listitem><para>Ratecontrol: constant quantizer, constant bitrate,
|
||||
or multipass ABR</para></listitem>
|
||||
<listitem><para>Scene cut detection</para></listitem>
|
||||
<listitem><para>Adaptive B-frame placement</para></listitem>
|
||||
<listitem><para>B-frames as references / arbitrary frame
|
||||
order</para></listitem>
|
||||
</itemizedlist>
|
||||
|
||||
<itemizedlist>
|
||||
<title>Encoder limitations</title>
|
||||
<listitem><para>No real RD</para></listitem>
|
||||
</itemizedlist>
|
||||
|
||||
|
||||
</sect4>
|
||||
|
||||
<sect4 id="codec-h264-whatis">
|
||||
<title>What is H.264?</title>
|
||||
<para>
|
||||
H.264 is one name for a new digital video codec jointly developed
|
||||
by the ITU and MPEG.
|
||||
It can also be correctly referred to by the cumbersome names of
|
||||
"ISO/IEC 14496-10" or "MPEG-4 Part 10".
|
||||
More frequently, it is referred to as "MPEG-4 AVC" or just "AVC".
|
||||
</para>
|
||||
<para>
|
||||
Whatever you call it, H.264 may be worth trying because it can
|
||||
typically match the quality of MPEG-4 ASP with 5%-30% less
|
||||
bitrate.
|
||||
Actual results will depend on both the source material and the
|
||||
encoder.
|
||||
The gains from using H.264 do not come for free: decoding H.264
|
||||
streams seems to have steep CPU and memory requirements.
|
||||
For instance, on a 1733 MHz Athlon, a 1500kbps H.264 video uses
|
||||
around 50% CPU to decode.
|
||||
By comparison, decoding a 1500kbps MPEG4-ASP stream requires
|
||||
around 10% CPU.
|
||||
This means that decoding high-definition streams is almost out of
|
||||
the question for most users.
|
||||
It also means that even a decent DVD rip may sometimes stutter on
|
||||
processors slower than 2.0 GHz or so.
|
||||
</para>
|
||||
<para>
|
||||
At least with <systemitem class="library">x264</systemitem>,
|
||||
encoding requirements are not much worse than what you are used to
|
||||
with MPEG4-ASP.
|
||||
For instance, on a 1733 MHz Athlon a typical DVD encode would run
|
||||
at 5-15fps.
|
||||
</para>
|
||||
<para>
|
||||
This document is not intended to explain the details of H.264,
|
||||
but if you are interested in a brief overview, you may want to read
|
||||
<ulink url="http://www.cdt.luth.se/~peppar/kurs/smd151/spie04-h264OverviewPaper.pdf">The H.264/AVC Advanced Video Coding Standard: Overview and Introduction to the Fidelity Range Extensions</ulink>.
|
||||
</para>
|
||||
</sect4>
|
||||
|
||||
<sect4 id="codec-x264-playback">
|
||||
<title>How can I play H.264 videos with <application>MPlayer</application>?</title>
|
||||
<para>
|
||||
<application>MPlayer</application> uses
|
||||
<systemitem class="library">libavcodec</systemitem>'s H.264
|
||||
decoder.
|
||||
<systemitem class="library">libavcodec</systemitem> has had at
|
||||
least minimally usable H.264 decoding since around July 2004,
|
||||
however major changes and improvements have been implemented since
|
||||
that time, both in terms of more functionalities supported and in
|
||||
terms of improved CPU usage.
|
||||
Just to be certain, it is always a good idea to use a recent CVS
|
||||
checkout.
|
||||
</para>
|
||||
<para>
|
||||
If you want a quick and easy way to know whether there have been
|
||||
recent changes to <systemitem class="library">libavcodec</systemitem>'s
|
||||
H.264 decoding, you might keep an eye on
|
||||
<ulink url="http://mplayerhq.hu/cgi-bin/cvsweb.cgi/ffmpeg/libavcodec/h264.c?cvsroot=FFMpeg">FFmpeg CVS repository's web interface</ulink>.
|
||||
</para>
|
||||
</sect4>
|
||||
|
||||
<sect4 id="codec-x264-encode">
|
||||
<title>How can I encode videos using <application>MEncoder</application> and <systemitem class="library">x264</systemitem>?</title>
|
||||
<para>
|
||||
If you have the subversion client installed, the latest x264
|
||||
sources can be gotten with this command:
|
||||
<screen>
|
||||
svn co svn://svn.videolan.org/x264/trunk x264
|
||||
</screen>
|
||||
<application>MPlayer</application> sources are updated whenever
|
||||
an <systemitem class="library">x264</systemitem> API change
|
||||
occurs, so it is always suggested to use CVS
|
||||
<application>MPlayer</application> as well.
|
||||
Perhaps this situation will change when and if an
|
||||
<systemitem class="library">x264</systemitem> "release" occurs.
|
||||
Meanwhile, <systemitem class="library">x264</systemitem> should
|
||||
be considered very unstable, in the sense that its programming
|
||||
interface is subject to change.
|
||||
</para>
|
||||
<para>
|
||||
<systemitem class="library">x264</systemitem> is built and
|
||||
installed in the standard way:
|
||||
<screen>
|
||||
./configure && make && sudo make install
|
||||
</screen>
|
||||
This installs libx264.a in /usr/local/lib and x264.h is placed in
|
||||
/usr/local/include.
|
||||
|
||||
With the <systemitem class="library">x264</systemitem> library
|
||||
and header placed in the standard locations, building
|
||||
<application>MPlayer</application> with
|
||||
<systemitem class="library">x264</systemitem> support is easy.
|
||||
Just run the standard:
|
||||
<screen>./configure && make && sudo make install</screen>
|
||||
The configure script will autodetect that you have satisfied the
|
||||
requirements for <systemitem class="library">x264</systemitem>.
|
||||
</para>
|
||||
</sect4>
|
||||
</sect3>
|
||||
</sect2>
|
||||
|
||||
|
Loading…
Reference in New Issue
Block a user