[gst-devel] Using gst-launch to convert between video formats on the command line?

Michael R. Head burner at suppressingfire.org
Fri Oct 27 13:02:18 CEST 2006

OK, I finally solved (most of) my gst-launch troubles. Here's what I
finally came up with:

gst-launch-0.10 --trace -m -v filesrc location=in.mkv ! matroskademux \
name=d d. ! queue ! faad ! lame  ! m.  d.video_00 ! queue ! m.video_00 \
avimux name=m ! filesink location=out.avi

I now understand that the .video_00 suffixes are necessary because the
pipeline can't otherwise figure out that we're looking for the video
channel because there's no video element inserted between the demux and
the mux (whereas there is an audio transcode step in the audio

Still, I do have a leftover issue with the outputted file. The audio is
severely out of sync with the video (by as much as 2 minutes by the end
of the file). In order to fix this, I have been running out.avi through
avidemux (copying the audio and video channels) in order to rebuild the
keyframes and to tweak the framerate (the file tells gstreamer it's 23
fps, but it's really 23.976. 

Is it possible to tweak my pipeline so that gstreamer builds the
keyframes and forces the framerate to be 23.976?

Thanks again,

On Mon, 2006-10-02 at 00:17 -0400, Michael R. Head wrote:
> Hi,
> I've got some video files in the matroska format that I would like to
> repack into the avi format. The codecs used in the file are Xvid and and
> AAC, and I'd like to simply reuse the audio and video bitstreams in the
> new file (I don't want to do any transcoding). So far, I've figured out
> how to take the video stream and put it into the avi, like so:
> gst-launch-0.10 filesrc location="in.mkv" ! matroskademux ! avimux ! filesink location=out.avi
> But the audio channel gets lost. What am I missing?
> thanks,
> mike
> -------------------------------------------------------------------------
> Take Surveys. Earn Cash. Influence the Future of IT
> Join SourceForge.net's Techsay panel and you'll get the chance to share your
> opinions on IT & business topics through brief surveys -- and earn cash
> http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV
> _______________________________________________ gstreamer-devel mailing list gstreamer-devel at lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/gstreamer-devel
Michael R. Head <burner at suppressingfire.org>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: This is a digitally signed message part
URL: <http://lists.freedesktop.org/archives/gstreamer-devel/attachments/20061027/1c8a57a2/attachment.pgp>

More information about the gstreamer-devel mailing list