====== Video Conversion ======

===== Tutorial =====
  * Installing ''FFmpeg'' on Mac OS X by Stephen Jungels: [[http://stephenjungels.com/jungels.net/articles/ffmpeg-howto.html]]

===== Required Programs =====
  * ''LAME'': [[http://lame.sourceforge.net/]]
  * ''FAAC'' and ''FAAD'': [[http://www.audiocoding.com/]]
  * ''YASM'': [[http://yasm.tortall.net/]]
  * ''FFmpeg'': [[http://ffmpeg.org/]]

Obtaining the source code and installation is pretty straightforward for the most part, basically just download the source code tar ball ( filename.tar.gz), decompress, untar, move to ''/usr/local/'' (optional), and follow the installation instruction in the ''INSTALL'' file included in the source code. In short, do:
<code bash>
sudo ./configure
sudo make
sudo make check
sudo make install
</code>

''FFmpeg'' is slightly different in that it is recommended to check out the latest version via ''svn'':
<code bash>
svn checkout svn://svn.ffmpeg.org/ffmpeg/trunk ffmpeg
</code>
The version that I got working on Mac OS 10.6.1 is:
<code bash>
Checked out external at revision 29714.
Checked out revision 20024.
</code>

Historically, I also had revision 19667 worked on Mac OS 10.5.8 and revision 19638 worked on Mac OS 10.5.7.

To configure and install, do:
<code bash>
./configure --enable-shared --enable-libmp3lame
</code>
The 2 additional arguments specify the build to enable shared libraries and ''LAME'' for mp3 support.

Because Mac OS 10.6 is a 64-bit OS, some additional flags are necessary when configuring the ''FFMpeg'':
<code bash>
./configure --enable-shared --enable-libmp3lame --extra-cflags=-m64 --extra-ldflags=-m64 --arch=x86_64
</code>

In the case that the code can not be compiled, disable the mmx support by:
<code bash>
./configure --enable-shared --enable-libmp3lame --disable-mmx
</code>
This may result in slower encoding but should reduce the trouble when compiling.

===== Example =====
To use ''FFmpeg'', the simplest command is:
<code bash>
ffmpeg -i input_file output_file
</code>
The program will recognize the file formats based on the filename extensions.


To add more control, run ''ffmpeg -h'' to see all possible options. The most commonly used ones include:
  * -b bitrate          => set video bitrate (in bits/s)
  * -r rate             => set frame rate (Hz value, fraction or abbreviation)
  * -s size             => set frame size (WxH or abbreviation)
  * -ab bitrate         => set audio bitrate (in bits/s)
  * -ar rate            => set audio sampling rate (in Hz)

For example:
<code>
ffmpeg -i input.AVI -b 600k -r 24 -s 640x480 -ab 96k -ar 44100 output.FLV
</code>

===== Player =====
  * [[http://www.videolan.org/vlc/|VLC]]: stand-alone media player
  * [[http://www.longtailvideo.com/players/jw-flv-player//|JW FLV Player]]: media player for ''HTML''-embedded ''flash'' files