[MPlayer-translations] CVS: main/DOCS/xml/ru codecs.xml,1.22,1.23

Diego Biurrun CVS syncmail at mplayerhq.hu
Thu May 5 15:27:01 CEST 2005


CVS change done by Diego Biurrun CVS

Update of /cvsroot/mplayer/main/DOCS/xml/ru
In directory mail:/var2/tmp/cvs-serv17707/ru

Modified Files:
	codecs.xml 
Log Message:
bandaid build fix


Index: codecs.xml
===================================================================
RCS file: /cvsroot/mplayer/main/DOCS/xml/ru/codecs.xml,v
retrieving revision 1.22
retrieving revision 1.23
diff -u -r1.22 -r1.23
--- codecs.xml	29 Nov 2004 19:43:29 -0000	1.22
+++ codecs.xml	5 May 2005 13:26:59 -0000	1.23
@@ -548,6 +548,149 @@
 </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 &amp;&amp; make &amp;&amp; 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 &amp;&amp; make &amp;&amp; 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>
 
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