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| author | diego <diego@b3059339-0415-0410-9bf9-f77b7e298cf2> | 2003-02-10 00:00:00 +0000 |
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| committer | diego <diego@b3059339-0415-0410-9bf9-f77b7e298cf2> | 2003-02-10 00:00:00 +0000 |
| commit | 41198d0c024dc57d005f839ddcde2e323b278b29 (patch) | |
| tree | c2f5ab2ace2fce23bcc095330ac8c16d929677de /DOCS/en/encoding.html | |
| parent | 3e718780f2dd3375f272c6e28becedd5f792f192 (diff) | |
| download | mpv-41198d0c024dc57d005f839ddcde2e323b278b29.tar.bz2 mpv-41198d0c024dc57d005f839ddcde2e323b278b29.tar.xz | |
Move English files to en/ subdirectory.
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diff --git a/DOCS/en/encoding.html b/DOCS/en/encoding.html new file mode 100644 index 0000000000..90bd251121 --- /dev/null +++ b/DOCS/en/encoding.html @@ -0,0 +1,320 @@ +<!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="mpeg">7.2 Encoding to MPEG format</A></H2> + +<P>MEncoder can create MPEG (MPEG-PS) format output files. It's probably + useful only with libavcodec's <I>mpeg1video</I> codec, because players + - except MPlayer - expect MPEG1 video, and MPEG1 layer 2 (MP2) audio streams + in MPEG files.</P> + +<P>This feature is not very useful right now, aside that it probably has + many bugs, but the more importantly because MEncoder currently cannot encode + MPEG1 layer 2 (MP2) audio, which all other players expect in MPEG files.</P> + +<P>To change MEncoder's output file format, use the <CODE>-of mpeg</CODE> + option.</P> + +<P>Example:<BR> + <CODE>mencoder -of mpeg -ovc lavc -lavcopts vcodec=mpeg1video + -oac copy <other options> media.avi -o output.mpg</CODE></P> + + +<H2><A NAME="rescaling">7.3 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> + +<H4>Usage:</H4> + +<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">7.4 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">7.5 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> + + +<H3><A NAME="appending">7.5.1 Appending multiple AVI files</A></H3> + +<P>As a side-effect, the broken AVI fixer function enables MEncoder to append + 2 (or more) AVI files:</P> + +<P>Command: <CODE>cat 1.avi 2.avi | mencoder -noidx -ovc copy -oac copy -o output.avi -</CODE></P> + +<P><B>Note:</B> This expects <CODE>1.avi</CODE> and <CODE>2.avi</CODE> to use the same codecs, resolution, + stream rate etc, and at least 1.avi must not be broken. You may need to fix + your input AVI files first, as described <A HREF="#fixing">above</A>.</P> + + +<H2><A NAME="libavcodec">7.6 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 5, 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">7.7 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 + man page.</P> + +<P><I>Creating a DivX4 file from all the JPEG files in the current dir:</I><BR> + <CODE>mencoder -mf on:w=800:h=600:fps=25 -ovc divx4 + -o output.avi \*.jpg</CODE></P> + +<P><I>Creating a DivX4 file from some JPEG files in the current dir:</I><BR> + <CODE>mencoder -mf on:w=800:h=600:fps=25 + -ovc divx4 -o output.avi frame001.jpg,frame002.jpg</CODE></P> + +<P><I>Creating a Motion JPEG (MJPEG) file from all the JPEG files in the current dir:</I><BR> + <CODE>mencoder -mf on:w=800:h=600:fps=25 -ovc copy + -o output.avi \*.jpg</CODE></P> + +<P><I>Creating an uncompressed file from all the PNG files in the current dir:</I><BR> + <CODE>mencoder -mf on:w=800:h=600:fps=25:type=png -ovc rawrgb + -o output.avi \*.png</CODE></P> + +<P><B>Note:</B> Width must be integer multiple of 4, it's a limitation of the + RAW RGB AVI format.</P> + +<P><I>Creating a Motion PNG (MPNG) file from all the PNG files in the current dir:</I><BR> + <CODE>mencoder -mf on:w=800:h=600:fps=25:type=png -ovc copy + -o output.avi \*.png</CODE></P> + +<P><I>Creating a Motion TGA (MTGA) file from all the TGA files in the current dir:</I><BR> + <CODE>mencoder -mf on:w=800:h=600:fps=25:type=tga -ovc copy + -o output.avi \*.tga</CODE></P> + + +<H2><A NAME="vobsub">7.8 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">7.9 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> + +<H4>Usage:</H4> + +<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> |