[MPlayer-DOCS] CVS: main/DOCS/xml/en mencoder.xml,1.75,1.76
Guillaume Poirier CVS
syncmail at mplayerhq.hu
Wed Jul 6 10:40:00 CEST 2005
CVS change done by Guillaume Poirier CVS
Update of /cvsroot/mplayer/main/DOCS/xml/en
In directory mail:/var2/tmp/cvs-serv29780/DOCS/xml/en
Modified Files:
mencoder.xml
Log Message:
Documentation for VCD/SVCD/DVD encoding, patch by Brendan McCarthy < bmccarthy AH iinet POUM net POUM au>
Index: mencoder.xml
===================================================================
RCS file: /cvsroot/mplayer/main/DOCS/xml/en/mencoder.xml,v
retrieving revision 1.75
retrieving revision 1.76
diff -u -r1.75 -r1.76
--- mencoder.xml 6 Jul 2005 07:56:41 -0000 1.75
+++ mencoder.xml 6 Jul 2005 08:39:57 -0000 1.76
@@ -2767,6 +2767,610 @@
</sect2>
</sect1>
+<sect1 id="menc-feat-vcd-dvd">
+<title>Using MEncoder to create VCD/SVCD/DVD-compliant files.</title>
+
+<sect2 id="menc-feat-vcd-dvd-constraints">
+<title>Format Constraints</title>
+<para>
+ <application>MEncoder</application> is capable of creating VCD, SCVD
+ and DVD format MPEG files using the
+ <systemitem class="library">libavcodec</systemitem> library.
+ These files can then be used in conjunction with
+ <ulink url="http://www.gnu.org/software/vcdimager/vcdimager.html">vcdimager</ulink>
+ or
+ <ulink url="http://dvdauthor.sourceforge.net/">dvdauthor</ulink>
+ to create discs that will play on a standard set-top player.
+</para>
+
+<para>
+ The DVD, SVCD, and VCD formats are subject to heavy constraints.
+ Only a small selection of encoded picture sizes and aspect ratios are
+ available.
+ If your movie does not already meet these requirements, you may have
+ to scale,crop or add black borders to the picture to make it
+ compliant.
+</para>
+
+<sect3 id="menc-feat-vcd-dvd-constraints-resolution">
+<title>Format Constraints</title>
+
+<informaltable frame="all">
+<tgroup cols="9">
+<thead>
+ <row>
+ <entry>Format</entry>
+ <entry>Resolution</entry>
+ <entry>V. Codec</entry>
+ <entry>V. Bitrate</entry>
+ <entry>Sample Rate</entry>
+ <entry>A. Codec</entry>
+ <entry>A. Bitrate</entry>
+ <entry>FPS</entry>
+ <entry>Aspect</entry>
+ </row>
+</thead>
+<tbody>
+ <row>
+ <entry>NTSC DVD</entry>
+ <entry>720x480, 704x480, 352x480, 352x240</entry>
+ <entry>MPEG-2</entry>
+ <entry>9800 kbps</entry>
+ <entry>48000 Hz</entry>
+ <entry>AC3,PCM</entry>
+ <entry>1536 kbps</entry>
+ <entry>23.976, 29.97</entry>
+ <entry>4:3, 16:9 (only for 720x480)</entry>
+ </row>
+ <row>
+ <entry>NTSC DVD</entry>
+ <entry>352x240*</entry>
+ <entry>MPEG-1</entry>
+ <entry>1856 kbps</entry>
+ <entry>48000 Hz</entry>
+ <entry>AC3,PCM</entry>
+ <entry>1536 kbps</entry>
+ <entry>23.976, 29.97</entry>
+ <entry>4:3, 16:9</entry>
+ </row>
+ <row>
+ <entry>NTSC SVCD</entry>
+ <entry>480x480</entry>
+ <entry>MPEG-2</entry>
+ <entry>2600 kbps</entry>
+ <entry>44100 Hz</entry>
+ <entry>MP2</entry>
+ <entry>384 kbps</entry>
+ <entry>29.97</entry>
+ <entry>4:3</entry>
+ </row>
+ <row>
+ <entry>NTSC VCD</entry>
+ <entry>352x240</entry>
+ <entry>MPEG-1</entry>
+ <entry>1150 kbps</entry>
+ <entry>44100 Hz</entry>
+ <entry>MP2</entry>
+ <entry>224 kbps</entry>
+ <entry>23.976, 29.97</entry>
+ <entry>4:3</entry>
+ </row>
+ <row>
+ <entry>PAL DVD</entry>
+ <entry>720x576, 704x576, 352x576, 352x288</entry>
+ <entry>MPEG-2</entry>
+ <entry>9800 kbps</entry>
+ <entry>48000 Hz</entry>
+ <entry>MP2,AC3,PCM</entry>
+ <entry>1536 kbps</entry>
+ <entry>25</entry>
+ <entry>4:3, 16:9 (only for 720x576)</entry>
+ </row>
+ <row>
+ <entry>PAL DVD</entry>
+ <entry>352x288*</entry>
+ <entry>MPEG-1</entry>
+ <entry>1856 kbps</entry>
+ <entry>48000 Hz</entry>
+ <entry>MP2,AC3,PCM</entry>
+ <entry>1536 kbps</entry>
+ <entry>25</entry>
+ <entry>4:3, 16:9</entry>
+ </row>
+ <row>
+ <entry>PAL SVCD</entry>
+ <entry>480x576</entry>
+ <entry>MPEG-2</entry>
+ <entry>2600 kbps</entry>
+ <entry>44100 Hz</entry>
+ <entry>MP2</entry>
+ <entry>384 kbps</entry>
+ <entry>25</entry>
+ <entry>4:3</entry>
+ </row>
+ <row>
+ <entry>PAL VCD</entry>
+ <entry>352x288</entry>
+ <entry>MPEG-1</entry>
+ <entry>1150 kbps</entry>
+ <entry>44100 Hz</entry>
+ <entry>MP2</entry>
+ <entry>224 kbps</entry>
+ <entry>25</entry>
+ <entry>4:3</entry>
+ </row>
+</tbody>
+</tgroup>
+</informaltable>
+<para>
+ * These resolutions are rarely used for DVDs because they are fairly low
+ quality.
+</para>
+
+<para>
+ If your movie has 2.35:1 aspect (most recent action movies), you will
+ have to add black borders or crop the movie down to 16:9 to make a DVD
+ or VCD.
+ If you add black borders, try to align them at 16-pixel boundaries in
+ order to minimize the impact on encoding performance.
+ Thankfully DVD has sufficiently excessive bitrate that you do not have
+ to worry too much about encoding efficiency, but SVCD and VCD are
+ highly bitrate-starved and require effort to obtain acceptable quality.
+</para>
+</sect3>
+
+<sect3 id="menc-feat-vcd-dvd-constraints-gop">
+<title>GOP Size Constraints</title>
+<para>
+ DVD, VCD, and SVCD also constrain you to relatively low
+ GOP (Group of Pictures) sizes.
+ For 30 fps material the largest allows GOP size is 18.
+ For 25 or 25 fps, the maximum is 15.
+ The GOP size is set using the <option>keyint</option> option.
+</para>
+</sect3>
+
+<sect3 id="menc-feat-vcd-dvd-constraints-bitrate">
+<title>Bitrate Constraints</title>
+<para>
+ VCD video is required to be CBR at 1152 kbps.
+ This highly limiting constraint also comes along with an extremly low vbv
+ buffer size of 327 kilobits.
+ SVCD allows varying video bitrates up to 2500 kbps, and a somewhat less
+ restrictive vbv buffer size of 917 kilobits is allowed.
+ DVD video bitrates may range anywhere up to 9800 kbps (though typical
+ bitrates are about half that), and the vbv buffer size is 1835 kilobits.
+</para>
+</sect3>
+</sect2>
+
+<sect2 id="menc-feat-vcd-dvd-output">
+<title>Output Options</title>
+<para>
+ <application>MEncoder</application> has options to control the output
+ format.
+ Using these options we can instruct it to create the correct type of
+ file.
+</para>
+
+<para>
+ The options for VCD and SVCD are called xvcd and xsvcd, because they
+ are extended formats.
+ They are not strictly compliant, mainly because the output does not
+ contain scan offsets.
+ If you need to generate an SVCD image, you should pass the output file
+ to
+ <ulink url="http://www.gnu.org/software/vcdimager/vcdimager.html">vcdimager</ulink>.
+</para>
+
+<para>
+ VCD:
+ <screen>
+ -of mpeg -mpegopts format=xvcd
+ </screen>
+</para>
+
+<para>
+ SVCD:
+ <screen>
+ -of mpeg -mpegopts format=xsvcd
+ </screen>
+</para>
+
+<para>
+ DVD:
+ <screen>
+ -of mpeg -mpegopts format=dvd
+ </screen>
+</para>
+
+<sect3 id="menc-feat-vcd-dvd-output-aspect">
+<title>Aspect Ratio</title>
+<para>
+ The aspect argument of <option>-lavcopts</option> is used to encode
+ the aspect ratio of the file.
+ During playback the aspect ratio is used to restore the video to the
+ correct size.
+</para>
+
+<para>
+ 16:9 or "Widescreen"
+ <screen>
+ -lavcopts aspect=16/9
+ </screen>
+</para>
+
+<para>
+ 4:3 or "Fullscreen"
+ <screen>
+ -lavcopts aspect=4/3
+ </screen>
+</para>
+
+<para>
+ 2.35:1 or "Cinemascope" NTSC
+ <screen>
+ -vf scale=720:368,expand=720:480 -lavcopts aspect=16/9
+ </screen>
+ To calculate the correct scaling size, use the expanded NTSC width of
+ 854/2.35 = 368
+</para>
+
+<para>
+ 2.35:1 or "Cinemascope" PAL
+ <screen>
+ -vf scale="720:432,expand=720:576 -lavcopts aspect=16/9
+ </screen>
+ To calculate the correct scaling size, use the expanded PAL width of
+ 1024/2.35 = 432
+</para>
+
+</sect3>
+
+<sect3 id="menc-feat-vcd-dvd-output-srate">
+<title>Sample Rate Conversion</title>
+<para>
+ If the audio sample rate in the original file is not the same as
+ required by the target format, sample rate conversion is required.
+ This is acheived using the <option>-srate</option> and
+ <option>-af lavcresample</option> options together.
+ </para>
+ <para>
+ DVD:
+ <screen>
+ -srate 48000 -af lavcresample=48000
+ </screen>
+</para>
+<para>
+ VCD and SVCD:
+ <screen>
+ -srate 44100 -af lavcresample=44100
+ </screen>
+ </para>
+</sect3>
+</sect2>
+
+<sect2 id="menc-feat-vcd-dvd-lavc">
+<title>Using libavcodec for VCD/SVCD/DVD Encoding</title>
+
+<sect3 id="menc-feat-vcd-dvd-lavc-intro">
+<title>Introduction</title>
+<para>
+ <systemitem class="library">libavcodec</systemitem> can be used to
+ create VCD/SVCD/DVD compliant video by using the appropriate options.
+</para>
+</sect3>
+
+<sect3 id="menc-feat-vcd-dvd-lavc-options">
+<title>lavcopts</title>
+<para>
+ This is a list of fields in <option>-lavcopts</option> that you may
+ be required to change in order to make a complaint movie for VCD, SVCD,
+ or DVD:
+</para>
+
+<itemizedlist>
+<listitem><para>
+ <emphasis role="bold">acodec</emphasis>:
+ <option>mp2</option> for VCD, SVCD, or PAL DVD;
+ <option>ac3</option> is most commonly used for DVD.
+ PCM audio may also be used for DVD, but this is mostly a big waste of
+ space.
+ Note that mp3 audio is not compliant for any of these formats, but
+ players often have no problem playing it anyway.
+</para></listitem>
+
+<listitem><para>
+ <emphasis role="bold">abitrate</emphasis>:
+ 224 for VCD; up to 384 for SVCD; up to 1536 for DVD, but commonly
+ used values range from 192 kbps for stereo to 384 kbps for 5.1 channel
+ sound.
+</para></listitem>
+
+<listitem><para>
+ <emphasis role="bold">vcodec</emphasis>:
+ <option>mpeg1video</option> for VCD;
+ <option>mpeg2video</option> for SVCD;
+ <option>mpeg2video</option> is usually used for DVD but you may also use
+ <option>mpeg1video</option> for CIF resolutions.
+</para></listitem>
+
+<listitem><para>
+ <emphasis role="bold">keyint</emphasis>:
+ Used to set the GOP size.
+ 18 for 30fps material, or 15 for 25/24 fps material.
+ Commercial producers seem to prefer keyframe intervals of 12.
+ It is possible to make this much larger and still retain compatibility
+ with most players.
+ A <option>keyint</option> of 25 should never cause any problems.
+</para></listitem>
+
+<listitem><para>
+ <emphasis role="bold">vrc_buf_size</emphasis>:
+ 327 for VCD, 917 for SVCD, and 1835 for DVD.
+</para></listitem>
+
+<listitem><para>
+ <emphasis role="bold">vrc_minrate</emphasis>:
+ 1152, for VCD. May be left alone for SVCD and DVD.
+</para></listitem>
+
+<listitem><para>
+ <emphasis role="bold">vrc_maxrate</emphasis>:
+ 1152 for VCD; 2500 for SVCD; 9800 for DVD.
+ For SVCD and DVD, you might wish to use lower values depending on your
+ own personal preferences and requirements.
+</para></listitem>
+
+<listitem><para>
+ <emphasis role="bold">vbitrate</emphasis>:
+ 1152 for VCD;
+ up to 2500 for SVCD;
+ up to 9800 for DVD.
+ For the latter two formats, vbitrate should be set based on personal
+ preference.
+ For instance, if you insist on fitting 20 or so hours on a DVD, you
+ could use vbitrate=400.
+ The resulting video quality would probably be quite bad.
+ If you are trying to squeeze out the maximum possible quality on a DVD,
+ use vbitrate=9800, but be warned that this could constrain you to less
+ than an hour of video on a single-layer DVD.
+</para></listitem>
+</itemizedlist>
+</sect3>
+
+<sect3 id="menc-feat-vcd-dvd-lavc-examples">
+<title>Examples</title>
+<para>
+ This is a typical minimum set of <option>-lavcopts</option> for
+ encoding video:
+</para>
+<para>
+ VCD:
+ <screen>
+ -lavcopts vcodec=mpeg1video:vrc_buf_size=327:vrc_minrate=1152:\
+ vrc_maxrate=1152:vbitrate=1152:keyint=15:acodec=mp2
+ </screen>
+</para>
+
+<para>
+ SVCD:
+ <screen>
+ -lavcopts vcodec=mpeg2video:vrc_buf_size=917:vrc_maxrate=2500:vbitrate=1800:\
+ keyint=15:acodec=mp2
+ </screen>
+</para>
+
+<para>
+ DVD:
+ <screen>
+ -lavcopts vcodec=mpeg2video:vrc_buf_size=1835:vrc_maxrate=9800:vbitrate=5000:\
+ keyint=15:acodec=ac3
+ </screen>
+</para>
+
+</sect3>
+
+<sect3 id="menc-feat-vcd-dvd-lavc-advanced">
+<title>Advanced Options</title>
+<para>
+ For higher quality encoding, you may also wish to add quality-enhancing
+ options to lavcopts, such as <option>trell</option>,
+ <option>mbd=2</option>, and others.
+ Note that <option>qpel</option> and <option>v4mv</option>, while often
+ useful with MPEG-4, are not usable in MPEG-1 or MPEG-2.
+ Also, if you are trying to make a very high quality DVD encode, it may
+ be useful to add <option>dc=10</option> to lavcopts.
+ Doing so may help reduce the appearance of blocks in flat-colored areas.
+ Putting it all together, this is an example of a set of lavcopts for a
+ higher quality DVD:
+</para>
+
+<para>
+ <screen>
+ -lavcopts vcodec=mpeg2video:vrc_buf_size=1835:vrc_maxrate=9800:vbitrate=8000:\
+ keyint=15:trell:mbd=2:precmp=2:subcmp=2:cmp=2:dia=-10:predia=-10:cbp:mv0:\
+ vqmin=1:lmin=1:dc=10
+ </screen>
+</para>
+
+</sect3>
+</sect2>
+
+<sect2 id="menc-feat-vcd-dvd-audio">
+<title>Encoding Audio</title>
+<para>
+ VCD and SVCD supports MPEG-1 layer II audio, using one of
+ <systemitem class="library">toolame</systemitem>,
+ <systemitem class="library">twolame</systemitem>,
+ or <systemitem class="library">libavcodec</systemitem>'s mp2 encoder.
+ The libavcodec mp2 is far from being as good as the other two libraries,
+ however it should always be available to use.
+</para>
+
+<para>
+ For DVD audio, <systemitem class="library">libavcodec</systemitem>'s
+ AC3 codec is used.
+</para>
+
+<sect3 id="menc-feat-vcd-dvd-audio-toolame">
+<title>toolame</title>
+<para>
+ For VCD and SVCD:
+ <screen>
+ -oac toolame -toolameopts br=224
+ </screen>
+</para>
+</sect3>
+
+<sect3 id="menc-feat-vcd-dvd-audio-twolame">
+<title>twolame</title>
+<para>
+ For VCD and SVCD:
+ <screen>
+ -oac twolame -twolameopts br=224
+ </screen>
+</para>
+</sect3>
+
+<sect3 id="menc-feat-vcd-dvd-audio-lavc">
+<title>libavcodec</title>
+<para>
+ For DVD with 2 channel sound:
+ <screen>
+ -oac lavc -lavcopts acodec=ac3:abitrate=192
+ </screen>
+</para>
+<para>
+ For DVD with 5.1 channel sound:
+ <screen>
+ -channels 6 -oac lavc -lavcopts acodec=ac3:abitrate=384
+ </screen>
+</para>
+<para>
+ For VCD and SVCD:
+ <screen>
+ -oac lavc -lavcopts acodec=mp2:abitrate=224
+ </screen>
+</para>
+</sect3>
+
+</sect2>
+
+<sect2 id="menc-feat-vcd-dvd-all">
+<title>Putting it all Together</title>
+<para>
+ This section shows some complete commands for creating VCD/SVCD/DVD
+ compliant videos.
+</para>
+
+<sect3 id="menc-feat-vcd-dvd-all-pal-dvd">
+<title>PAL DVD</title>
+<para>
+ <screen>
+ mencoder -oac lavc -ovc lavc -of mpeg -mpegopts format=dvd -vf scale=720:576,\
+ harddup -srate 48000 -af lavcresample=48000 -lavcopts vcodec=mpeg2video:\
+ vrc_buf_size=1835:vrc_maxrate=9800:vbitrate=5000:keyint=15:acodec=ac3:\
+ abitrate=192:aspect=16/9 -ofps 25 \
+ -o <replaceable>movie.mpg</replaceable> <replaceable>movie.avi</replaceable>
+ </screen>
+</para>
+</sect3>
+
+<sect3 id="menc-feat-vcd-dvd-all-ntsc-dvd">
+<title>NTSC DVD</title>
+<para>
+ <screen>
+ mencoder -oac lavc -ovc lavc -of mpeg -mpegopts format=dvd -vf scale=720:480,\
+ harddup -srate 48000 -af lavcresample=48000 -lavcopts vcodec=mpeg2video:\
+ vrc_buf_size=1835:vrc_maxrate=9800:vbitrate=5000:keyint=18:acodec=ac3:\
+ abitrate=192:aspect=16/9 -ofps 30000/1001 \
+ -o <replaceable>movie.mpg</replaceable> <replaceable>movie.avi</replaceable>
+ </screen>
+</para>
+</sect3>
+
+<sect3 id="menc-feat-vcd-dvd-all-pal-ac3-copy">
+<title>PAL AVI Containing AC3 Audio to DVD</title>
+<para>
+ If the source already has AC3 audio, use -oac copy instead of re-encoding it.
+ <screen>
+ mencoder -oac copy -ovc lavc -of mpeg -mpegopts format=dvd -vf scale=720:576,\
+ harddup -lavcopts vcodec=mpeg2video:vrc_buf_size=1835:vrc_maxrate=9800:\
+ vbitrate=5000:keyint=15:aspect=16/9 -ofps 25 \
+ -o <replaceable>movie.mpg</replaceable> <replaceable>movie.avi</replaceable>
+ </screen>
+</para>
+</sect3>
+
+<sect3 id="menc-feat-vcd-dvd-all-ntsc-ac3-copy">
+<title>NTSC AVI Containing AC3 Audio to DVD</title>
+<para>
+ If the source already has AC3 audio, and is NTSC @ 23.976 fps:
+ <screen>
+ mencoder -oac copy -ovc lavc -of mpeg -mpegopts format=dvd -vf scale=720:480,\
+ harddup -lavcopts vcodec=mpeg2video:vrc_buf_size=1835:vrc_maxrate=9800:\
+ vbitrate=5000:keyint=15:aspect=16/9 -ofps 24000/1001 \
+ -o <replaceable>movie.mpg</replaceable> <replaceable>movie.avi</replaceable>
+ </screen>
+</para>
+</sect3>
+
+<sect3 id="menc-feat-vcd-dvd-all-pal-svcd">
+<title>PAL SVCD</title>
+<para>
+ <screen>
+ mencoder -oac lavc -ovc lavc -of mpeg -mpegopts format=xsvcd -vf \
+ scale=480:576,harddup -srate 44100 -af lavcresample=44100 -lavcopts \
+ vcodec=mpeg2video:mbd=2:keyint=15:vrc_buf_size=917:vrc_minrate=600:\
+ vbitrate=2500:vrc_maxrate=2500:acodec=mp2:abitrate=224 -ofps 25 \
+ -o <replaceable>movie.mpg</replaceable> <replaceable>movie.avi</replaceable>
+ </screen>
+</para>
+</sect3>
+
+<sect3 id="menc-feat-vcd-dvd-all-ntsc-svcd">
+<title>NTSC SVCD</title>
+<para>
+ <screen>
+ mencoder -oac lavc -ovc lavc -of mpeg -mpegopts format=xsvcd -vf \
+ scale=480:480,harddup -srate 44100 -af lavcresample=44100 -lavcopts \
+ vcodec=mpeg2video:mbd=2:keyint=18:vrc_buf_size=917:vrc_minrate=600:\
+ vbitrate=2500:vrc_maxrate=2500:acodec=mp2:abitrate=224 -ofps 30000/1001 \
+ -o <replaceable>movie.mpg</replaceable> <replaceable>movie.avi</replaceable>
+ </screen>
+</para>
+</sect3>
+
+<sect3 id="menc-feat-vcd-dvd-all-pal-vcd">
+<title>PAL VCD</title>
+<para>
+ <screen>
+ mencoder -oac lavc -ovc lavc -of mpeg -mpegopts format=xvcd -vf \
+ scale=352:288,harddup -srate 44100 -af lavcresample=44100 -lavcopts \
+ vcodec=mpeg1video:keyint=15:vrc_buf_size=327:vrc_minrate=1152:vbitrate=1152:\
+ vrc_maxrate=1152:acodec=mp2:abitrate=224 -ofps 25 \
+ -o <replaceable>movie.mpg</replaceable> <replaceable>movie.avi</replaceable>
+ </screen>
+</para>
+</sect3>
+
+<sect3 id="menc-feat-vcd-dvd-all-ntsc-vcd">
+<title>NTSC VCD</title>
+<para>
+ <screen>
+ mencoder -oac lavc -ovc lavc -of mpeg -mpegopts format=xvcd -vf \
+ scale=352:240,harddup -srate 44100 -af lavcresample=44100 -lavcopts \
+ vcodec=mpeg1video:keyint=18:vrc_buf_size=327:vrc_minrate=1152:vbitrate=1152:\
+ vrc_maxrate=1152:acodec=mp2:abitrate=224 -ofps 30000/1001 \
+ -o <replaceable>movie.mpg</replaceable> <replaceable>movie.avi</replaceable>
+ </screen>
+</para>
+</sect3>
+
+</sect2>
+
+</sect1>
<sect1 id="menc-feat-telecine">
<title>How to deal with telecine and interlacing within NTSC DVDs</title>
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