Flash Video

flv	VLC can decode this container. The module name to use at the command line is flv.

Flash Video is a file format mainly used for playing data in a Flash player on a webpage. It has the extension .flv.

There are two types of flv files, the one based on H.263 (which exists since Flash 6) and another based on VP6 (which was introduced in Flash 8). In Flash 9 Update 3 Adobe added support for MPEG-4, thus since this version flv files may also contain H.264 and HE-AAC.

Compatibility

H.263 flash video is supported by the latest VLC, with some bugs. There is a workaround using ffmpeg for this. VP6 is also supported by VLC from version 0.8.6b and above.

However, seeking, (that is, jumping to a position in the video) is not supported until 0.9.0 in either codecs.

Streaming Flash Video With VLC

Starting from VLC revision 18876 (which means 0.9.0-svn after 17/02/2007), you can stream flash with VLC. You also need to build VLC with a fairly recent ffmpeg version (r7593 21/01/2007 or newer).

You can then use the following command line to do HTTP Flash Video streaming:

% ./vlc <input> --sout "#transcode{vcodec=FLV1,acodec=mp3}:std{access=http,dst=/stream.flv}"

You can then point any flash based player to that stream using http://192.2.0.1:8080/stream.flv where 192.2.0.1 is the server IP address.

Note that flash only accepts 3 audio sample rates (44.1 kHz, 22.05 kHz and 11.025 kHz). If your source audio uses something else, muxing will fail. You can change the sampling rate by adding samplerate=44100 in transcode.

Note: this and many other video codecs appear to be disabled and silently not working on Windows binaries, the system won't complain, but all you find is a container with no video stream in it.