I was looking for a way to convert some Video and Sound files, downloaded from Youtube (mostly things dedicated to free software) and as far as I looked online unfortunately these pieces of nice music and tutorials are not available for download anywhere else or at least not available for download in some of the Open / Free Format (OGG Vorbis or OGV (OGG / Theora Video).
When it comes to convertion between different formats, always the first things that I think of is ffmpeg or mencoder , however I was not sure if some of this tools are doing the trick so I did a quick research online if there is some specialised console or GUI program that can do the convertions between MP4, FLV etc. to OGV.
In less than 10 minutes I found a threat mentioning about ffmpeg2theora – A Simple Convertor to create Ogg Theora files
As I’m running Debian GNU / Linux, I installed ffmpeg2theora straight via apt, according to some reports online ffmpeg2theora cmd convertion tool is also available straight from repositories on Ubuntu as well.
On FreeBSD there is a port /usr/ports/multimedia/ffmpeg2theora available for install. Of course FFmpeg2Theora can be installed from source on other Linux distributions that might be missing a pre-built binary.
Using ffmpeg2theora to convert some kind of non-free video format is very simple, though the tool provides quite a numerous options for all those who want to have some customization for the video to be converted.
To convert the flash file “The Gnu Song.flv” for example to The Gnu Song.flv , I invoked ffmpeg2theora like this:
debian:~# ffmpeg2theora "The Gnu Song.flv"
...
The conversion took few minutes of time, as my machine is not ultra powerful and apparently the conversion to OGV format is not too quick but the good news is it works.
After the conversion was completed I used ogginfo to check the information about the recent converted file The Gnu Song.flv , below you see the file info ogginfo returns
debian:~# ogginfo The Gnu Song.ogv
Processing file "The Gnu Song.ogv"...
New logical stream (#1, serial: 5d65413f): type skeleton
New logical stream (#2, serial: 0570412d): type theora
New logical stream (#3, serial: 7e679651): type vorbis
Theora headers parsed for stream 2, information follows…
Version: 3.2.1
Vendor: Xiph.Org libtheora 1.1 20090822 (Thusnelda)
Width: 320
Height: 240
Total image: 320 by 240, crop offset (0, 0)
Framerate 25/1 (25.00 fps)
Aspect ratio undefined
Colourspace: Rec. ITU-R BT.470-6 Systems B and G (PAL)
Pixel format 4:2:0
Target bitrate: 0 kbps
Nominal quality setting (0-63): 32
User comments section follows…
ENCODER=ffmpeg2theora-0.24
Vorbis headers parsed for stream 3, information follows…
Version: 0
Vendor: Xiph.Org libVorbis I 20101101 (Schaufenugget)
Channels: 1
Rate: 22050
Nominal bitrate: 30.444000 kb/s
Upper bitrate not set
Lower bitrate not set
User comments section follows…
ENCODER=ffmpeg2theora-0.24
Logical stream 1 ended
Theora stream 2:
Total data length: 1525324 bytes
Playback length: 2m:41.360s
Average bitrate: 75.623401 kb/s
Logical stream 2 ended
Vorbis stream 3:
Total data length: 646729 bytes
Playback length: 2m:41.384s
Average bitrate: 32.059041 kb/s
ogginfo is a part of a package installed under the name vorbis-tools, vorbis tools also contains a few other helpful tools, whether operations with OGV or OGG file formats are at hand, the complete binaries vorbis-tools contains on Debian as of time of writting this post is:
/usr/bin/ogg123
/usr/bin/oggenc
/usr/bin/oggdec
/usr/bin/ogginfo
/usr/bin/vcut
/usr/bin/vorbiscomment
/usr/bin/vorbistagedit
ogg123 is a player for ogg files, however as far as I’ve tested it it doesn’t work too well. And just to compare ogg audio files were played just nice using the play command.
oggenc is used to encode ogg audio file, based on a stream haneded to it from other audio encoded stream (let’s say mp3). Hence oggenc can be used to convert mp3 files to ogg audio files , like so:
debian:~# mpg321 input.mp3 -w - | oggenc -o output.ogg -
oggdec is used to convert to wav files or raw PCM audio, whether;
vcut is used to cut ogg video file on parts.
vorbiscomment and vorbistagedit is used to edit information on already existing ogg audio files
There is also a GUI programmer for people who doesn’t want to bother with writting on the command line called oggconvert . OggConvert is written for GNOME and uses GTK gnome library, here is how the program looks like:
