Hi Mike, Thanks for your reply. I created this file using Media Foundation on Windows. When I read the same file on Windows and Mac, it identifies the audio stream to have only 1 channel. Could this be a bug with Faad? Regards, Dinesh <div class="gmail_quote">On Wed, Feb 8, 2012 at 1:40 PM, Michael Smith <<a href="mailto:msmith@xiph.org">msmith@xiph.org</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> As you can see from the image you attached, the input to FAAD says it's mono (channels=1), but the output from FAAD has channels=2. This probably means that it's marked as mono in the container (mp4), but is actually stereo - faad cares more about the actual AAC contents than about what the container says, so overrides it. So this is happening solely inside faad - it's not gstreamer converting to another format or anything complex like that. I guess you don't really have a mono AAC file. Mike <div><div class="h5"> On Wed, Feb 8, 2012 at 9:09 AM, Dinesh Iyer <<a href="mailto:dsi.maillist@gmail.com">dsi.maillist@gmail.com</a>> wrote: > Hello, > I am using playbin2 to read audio data from AAC and MP3 files. I noticed > that when I attempt to read one channel AAC files, the output returned is > stereo with both channels having the same data. Single channel MP3 and WAV > files were read in as expected. I am attaching an image of the pipeline > obtained when using the following gst-launch command: > > gst-launch-0.10 playbin2 > uri=file:///local/playbin2_appsink_aac_mono/testWelcomeMono.m4a > audio-sink=appsink video-sink=fakesink text-sink=fakesink > > > > Regards, > Dinesh > </div></div>> _______________________________________________ > gstreamer-devel mailing list > <a href="mailto:gstreamer-devel@lists.freedesktop.org">gstreamer-devel@lists.freedesktop.org</a> > <a href="http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel" target="_blank">http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel</a> > _______________________________________________ gstreamer-devel mailing list <a href="mailto:gstreamer-devel@lists.freedesktop.org">gstreamer-devel@lists.freedesktop.org</a> <a href="http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel" target="_blank">http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel</a> </blockquote></div>