mirror of https://github.com/mpv-player/mpv
287 lines
12 KiB
HTML
287 lines
12 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
|
|
<HTML>
|
|
|
|
<HEAD>
|
|
<TITLE>Encoding - MEncoder - The Movie Encoder 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>
|
|
|
|
|
|
<H1><A NAME="encoding">7. Encoding with MEncoder</A></H1>
|
|
|
|
<P>For the complete list of available MEncoder options and examples, please see
|
|
the man page. For a series of hands-on examples and detailed guides on using
|
|
several encoding parameters, read the
|
|
<A HREF="tech/encoding-tips.txt">encoding-tips</A> that were collected from
|
|
several mailing list threads on
|
|
<A HREF="http://mplayerhq.hu/mailman/listinfo/mplayer-users">mplayer-users</A>.
|
|
Search the <A HREF="http://mplayerhq.hu/pipermail/mplayer-users/">archives</A>
|
|
for a wealth of discussions about all aspects of and problems related to
|
|
encoding with MEncoder.</P>
|
|
|
|
|
|
<H2><A NAME="2pass">7.1 Encoding 2 or 3-pass MPEG-4 ("DIVX")</A></H2>
|
|
|
|
<P><U><B>2-pass encoding:</B></U> the name comes from the fact that this method
|
|
encodes the file <I>twice</I>. The first encoding (dubbed <I>pass</I>)
|
|
creates some temporary files (*.log) with a size of few megabytes, do not
|
|
delete them yet (you can delete the AVI). In the second pass, the 2-pass
|
|
output file is created, using the bitrate data from the temporary files. The
|
|
resulting file will have much better image quality. If this is the first time
|
|
you heard about this, you should consult some guides available on the
|
|
Net.</P>
|
|
|
|
<P>This example shows how to encode a DVD to a 2-pass MPEG-4 ("DIVX") AVI. Just
|
|
two commands are needed:<BR>
|
|
<CODE> rm frameno.avi</CODE> - remove this file, which
|
|
can come from a previous 3-pass encoding (it interferes with current
|
|
one)<BR>
|
|
<CODE> mencoder -dvd 2 -ovc lavc -lavcopts
|
|
vcodec=mpeg4:vpass=1 -oac copy -o movie.avi<BR>
|
|
mencoder -dvd 2 -ovc lavc -lavcopts
|
|
vcodec=mpeg4:vpass=2 -oac copy -o movie.avi</CODE></P>
|
|
|
|
<P><U><B>3-pass encoding:</B></U> this is an extension of 2-pass encoding,
|
|
where the audio encoding takes place in a separate pass. This method enables
|
|
estimation of recommended video bitrate in order to fit on a CD. Also, the
|
|
audio is encoded only once, unlike in 2-pass mode. The schematics:</P>
|
|
|
|
<OL>
|
|
<LI>Remove conflicting temporary file:
|
|
<P><CODE>rm frameno.avi</CODE></P></LI>
|
|
<LI>First pass:
|
|
<P><CODE>mencoder <file/DVD> -ovc frameno -oac mp3lame -lameopts vbr=3 -o frameno.avi</CODE></P>
|
|
<P>An audio-only avi file will be created, containing
|
|
<B>only</B> the requested audio stream. Don't forget <CODE>-lameopts</CODE>,
|
|
if you need to set it. If you were encoding a long movie, MEncoder
|
|
prints the recommended bitrate values for 650Mb, 700Mb, and 800Mb
|
|
destination sizes, after this pass finishes.</P></LI>
|
|
<LI>Second pass:
|
|
<P><CODE>mencoder <file/DVD> -oac copy
|
|
-ovc lavc -lavcopts vcodec=mpeg4:vpass=1:vbitrate=<bitrate></CODE></P>
|
|
<P>This is the first pass of video encoding.
|
|
Optionally specify the video bitrate MEncoder printed at the end of
|
|
the previous pass.</P></LI>
|
|
<LI>Third pass:
|
|
<P><CODE>mencoder <file/DVD> -oac copy
|
|
-ovc lavc -lavcopts vcodec=mpeg4:vpass=2:vbitrate=<bitrate></CODE></P>
|
|
<P>This is the second pass of video encoding.
|
|
Specify the same bitrate as in the previous pass unless you really know
|
|
what you are doing. In this pass, audio from <CODE>frameno.avi</CODE>
|
|
will be inserted into the destination file.. and it's all ready!</P></LI>
|
|
</OL>
|
|
|
|
<H4>Example for 3-pass encoding:</H4>
|
|
|
|
<P><CODE> rm frameno.avi</CODE> - remove this file,
|
|
which can come from a previous 3-pass encoding (it interferes with current
|
|
one)<BR>
|
|
<CODE> mencoder -dvd 2 -ovc frameno
|
|
-o frameno.avi -oac mp3lame -lameopts vbr=3<BR>
|
|
mencoder -dvd 2 -ovc lavc
|
|
-lavcopts vcodec=mpeg4:vpass=1 -oac copy -o movie.avi<BR>
|
|
mencoder -dvd 2 -ovc lavc
|
|
-lavcopts vcodec=mpeg4:vpass=2 -oac copy -o movie.avi</CODE></P>
|
|
|
|
|
|
<H2><A NAME="rescaling">7.2 Rescaling movies</A></H2>
|
|
|
|
<P>Often the need to resize movie images' size emerges. Its reasons can be
|
|
many: decreasing file size, network bandwidth, etc. Most people
|
|
even do rescaling when converting DVDs or SVCDs to DivX AVI. <B>This is bad.</B>
|
|
Instead of even you doing so, read the <A HREF="#aspect">Preserving
|
|
aspect ratio</A> section.</P>
|
|
|
|
<P>The scaling process is handled by the <I>'scale'</I> video filter:
|
|
<CODE>-vop scale=widht:height</CODE>. Its quality can be set with the
|
|
<CODE>-sws</CODE> option. If it's not specified, MEncoder will use 0:
|
|
fast bilinear.</P>
|
|
|
|
<H5>Usage:</H5>
|
|
|
|
<P><CODE> mencoder input.mpg -ovc lavc -lavcopts
|
|
vcodec=mpeg4 -vop scale=640:480 -oac copy -o
|
|
output.avi</CODE></P>
|
|
|
|
|
|
<H2><A NAME="copying">7.3 Stream copying</A></H2>
|
|
|
|
<P>MEncoder can handle input streams in two ways: <B>encode</B> or
|
|
<B>copy</B> them. This section is about <B>copying</B>.</P>
|
|
|
|
<UL>
|
|
<LI><B>Video stream</B> (option <CODE>-ovc copy</CODE>): nice stuff can be
|
|
done :)<BR>
|
|
Like, putting (not converting) FLI or VIVO or MPEG1 video into
|
|
an AVI file. Of course only MPlayer can play such files :) And it
|
|
probably has no real life value at all. Rationally: video stream copying
|
|
can be useful for example when only the audio stream has to be encoded
|
|
(like, uncompressed PCM to MP3).</LI>
|
|
|
|
<LI><B>Audio stream</B> (option <CODE>-oac copy</CODE>): straightforward.
|
|
It is possible to take an external audio file (MP3, Vorbis) and mux it
|
|
into the output stream. Use the <CODE>-audiofile <filename></CODE>
|
|
option for this.</LI>
|
|
</UL>
|
|
|
|
|
|
<H2><A NAME="fixing">7.4 Fixing AVIs with broken index or interleaving</A></H2>
|
|
|
|
<P>Easiest thing. We simply copy the video and audio streams, and
|
|
MEncoder generates the index. Of course this cannot fix possible bugs
|
|
in the video and/or audio streams. It also fixes files with broken
|
|
interleaving, thus the <CODE>-ni</CODE> option won't be needed for them
|
|
anymore.</P>
|
|
|
|
<P>Command: <CODE>mencoder -idx input.avi -ovc copy -oac copy -o output.avi</CODE></P>
|
|
|
|
|
|
<H2><A NAME="libavcodec">7.5 Encoding with the libavcodec codec family</A></H2>
|
|
|
|
<P><A HREF="codecs.html#libavcodec">libavcodec</A> provides simple encoding to a
|
|
lot of interesting video and audio formats (currently its audio codecs are
|
|
unsupported). You can encode to the following codecs:</P>
|
|
|
|
<UL>
|
|
<LI>mjpeg - Motion JPEG</LI>
|
|
<LI>h263 - H263</LI>
|
|
<LI>h263p - H263 Plus</LI>
|
|
<LI>mpeg4 - ISO standard MPEG-4 (DivX 4/5, OpenDivX, XVID compatible)</LI>
|
|
<LI>msmpeg4 - pre-standard MPEG-4 variant by MS, v3 (aka DivX3)</LI>
|
|
<LI>msmpeg4v2 - pre-standard MPEG-4 by MS, v2 (used in old asf files)</LI>
|
|
<LI>wmv1 - Windows Media Video, version 1 (aka WMV7)</LI>
|
|
<LI>rv10 - an old RealVideo codec</LI>
|
|
<LI>mpeg1video - MPEG1 video :)</LI>
|
|
<LI>huffyuv - lossless compression</LI>
|
|
</UL>
|
|
|
|
<P>The first column contains the codec names that should be passed after the
|
|
<CODE>vcodec</CODE> config, like: <CODE>-lavcopts vcodec=msmpeg4</CODE></P>
|
|
|
|
<P>An example, with MJPEG compression:<BR>
|
|
<CODE> mencoder -dvd 2 -o title2.avi -ovc lavc
|
|
-lavcopts vcodec=mjpeg -oac copy</CODE></P>
|
|
|
|
|
|
<H2><A NAME="image_files">7.6 Encoding from multiple input image files (JPEGs, PNGs or TGAs)</A></H2>
|
|
|
|
<P>MEncoder is capable of creating movies from one or more JPEG, PNG or TGA
|
|
files. With simple framecopy it can create MJPEG (Motion JPEG), MPNG
|
|
(Motion PNG) or MTGA (Motion TGA) files.</P>
|
|
|
|
Explanation of the process:
|
|
|
|
<OL>
|
|
<LI>MEncoder <I>decodes</I> the input image(s) with
|
|
<CODE>libjpeg</CODE> (when decoding PNGs, it will use <B>libpng</B>).</LI>
|
|
|
|
<LI>MEncoder then feeds the decoded image to the chosen video compressor
|
|
(DivX4, Xvid, ffmpeg msmpeg4, etc...).</LI>
|
|
</OL>
|
|
|
|
<H4>Examples</H4>
|
|
|
|
<P>The explanation of the <CODE>-mf</CODE> option can be found below in the
|
|
global <A HREF="#options">Options</A> section and in the man page.</P>
|
|
|
|
<P><I>Creating a DivX4 file from all the JPEG files in the current dir:</I><BR>
|
|
<CODE>mencoder \*.jpg -mf on:w=800:h=600:fps=25 -ovc divx4
|
|
-o output.avi</CODE></P>
|
|
|
|
<P><I>Creating a DivX4 file from some JPEG files in the current dir:</I><BR>
|
|
<CODE>mencoder frame001.jpg,frame002.jpg -mf on:w=800:h=600:fps=25
|
|
-ovc divx4 -o output.avi</CODE></P>
|
|
|
|
<P><I>Creating a Motion JPEG (MJPEG) file from all the JPEG files in the current dir:</I><BR>
|
|
<CODE>mencoder \*.jpg -mf on:w=800:h=600:fps=25 -ovc copy
|
|
-o output.avi</CODE></P>
|
|
|
|
<P><I>Creating an uncompressed file from all the PNG files in the current dir:</I><BR>
|
|
<CODE>mencoder \*.png -mf on:w=800:h=600:fps=25:type=png -ovc raw
|
|
-o output.avi</CODE></P>
|
|
|
|
<P><I>Creating a Motion PNG (MPNG) file from all the PNG files in the current dir:</I><BR>
|
|
<CODE>mencoder \*.png -mf on:w=800:h=600:fps=25:type=png -ovc copy
|
|
-o output.avi</CODE></P>
|
|
|
|
<P><I>Creating a Motion TGA (MTGA) file from all the TGA files in the current dir:</I><BR>
|
|
<CODE>mencoder \*.tga -mf on:w=800:h=600:fps=25:type=tga -ovc copy
|
|
-o output.avi</CODE></P>
|
|
|
|
|
|
<H2><A NAME="vobsub">7.7 Extracting DVD subtitles to a Vobsub file</A></H2>
|
|
|
|
<P>MEncoder is capable of extracting subtitles from a DVD into
|
|
Vobsub fomat files. They consist of a pair of files ending in
|
|
<CODE>.idx</CODE> and <CODE>.sub</CODE> and are usually packaged in a single
|
|
<CODE>.rar</CODE> archive. MPlayer can play these with the
|
|
<CODE>-vobsub</CODE> and <CODE>-vobsubid</CODE> options.</P>
|
|
|
|
<P>You specify the basename (i.e without the <CODE>.idx</CODE> or
|
|
<CODE>.sub</CODE> extension) of the output files with <CODE>-vobsubout</CODE>
|
|
and the index for this subtitle in the resulting files with
|
|
<CODE>-vobsuboutindex</CODE>.</P>
|
|
|
|
<P>If the input is not from a DVD you should use <CODE>-ifo</CODE> to
|
|
indicate the <CODE>.ifo</CODE> file needed to construct the resulting
|
|
<CODE>.idx</CODE> file.</P>
|
|
|
|
<P>If the input is not from a DVD and you do not have the <CODE>.ifo</CODE>
|
|
file you will need to use the <CODE>-vobsubid</CODE> option to let it know
|
|
what language id to put in the <CODE>.idx</CODE> file.</P>
|
|
|
|
<P>Each run will append the running subtitle if the <CODE>.idx</CODE> and
|
|
<CODE>.sub</CODE> files already exist. So you should remove any before
|
|
starting.</P>
|
|
|
|
<H4>Examples</H4>
|
|
|
|
<P><I>Copying two subtitles from a DVD while doing 3-pass encoding</I><BR>
|
|
<CODE>rm subtitles.idx subtitles.sub</CODE><BR>
|
|
<CODE>mencoder -dvd 1 -vobsubout subtitles -vobsuboutindex 0
|
|
-sid 2 -o frameno.avi -ovc frameno -oac mp3lame -lameopts vbr=3</CODE><BR>
|
|
<CODE>mencoder -dvd 1 -oac copy -ovc divx4 -divx4opts pass=1</CODE><BR>
|
|
<CODE>mencoder -dvd 1 -oac copy -ovc divx4 -divx4opts pass=2 -vobsubout
|
|
subtitles -vobsuboutindex 1 -sid 5</CODE></P>
|
|
|
|
<P><I>Copying a french subtitle from an MPEG file</I><BR>
|
|
<CODE>rm subtitles.idx subtitles.sub</CODE><BR>
|
|
<CODE>mencoder movie.mpg -ifo movie.ifo -vobsubout subtitles
|
|
-vobsuboutindex 0 -vobsuboutid fr -sid 1</CODE></P>
|
|
|
|
|
|
<H2><A NAME="aspect">7.8 Preserving aspect ratio</A></H2>
|
|
|
|
<P>DVDs and SVCDs (i.e. MPEG1/2) files contain an aspect ratio value,
|
|
which describes how should the player scale the video stream, so humans
|
|
won't have egg heads (ex.: 480x480 + 4:3 = 640x480). However when encoding
|
|
to AVI (DivX) files, you have be aware that AVI headers don't store this
|
|
value. Rescaling the movie is disgusting and time consuming, there
|
|
must be a better feature!</P>
|
|
|
|
<P>There is.</P>
|
|
|
|
<P>MPEG4 has an unique feature: the video stream can contain
|
|
its needed aspect ratio. Yes, just like MPEG1/2 files (DVD, SVCD).
|
|
Regretfully, there are <U>no</U> video players outside which support this
|
|
attribute. Except MPlayer.</P>
|
|
|
|
<P>This feature can be used only with <B>libavcodec</B>'s <CODE>mpeg4</CODE>
|
|
codec. Keep in mind: although MPlayer will correctly play the created file,
|
|
other players will use the wrong aspect ratio.</P>
|
|
|
|
<P>You seriously should crop the black bands over and below the movie image.
|
|
See the manpage about the usage of the <CODE>cropdetect</CODE> and
|
|
<CODE>crop</CODE> filters.</P>
|
|
|
|
<H5>Usage:</H5>
|
|
|
|
<P><CODE>$ mencoder sample-svcd.mpg -ovc lavc -lavcopts
|
|
vcodec=mpeg4:aspect=16.0/9.0 -vop crop=714:548:0:14 -oac copy -o output.avi</CODE></P>
|
|
|
|
</BODY>
|
|
</HTML>
|