Hi Felipe, Thanks a lot for your reply. I am looking into the alternatives to implement this. Just wanted to make sure I am not re-inventing the wheel. If anyone has better ideas or has implemented this let me know. Can you tell me why the audio sink implementation uses GstBaseSink instead of GstAudioBaseSink which might have provided clock features to implement and set the master clock? >>Then there's the problem of A/V sync. This has been discussed in the >>past and the consensus is that the best way to implement this would be >>to map OpenMAX IL clock to GStreamer's clock. I will go through this. Please give me more pointers if we have a plugin for clock component in gst-openmax? Thanks, Nitin <div class="gmail_quote"> On Wed, Feb 17, 2010 at 4:40 PM, Felipe Contreras <<a href="mailto:felipe.contreras@gmail.com">felipe.contreras@gmail.com</a>> wrote: <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> Hi Nitin, <div><div></div><div class="h5"> On Mon, Feb 8, 2010 at 11:25 AM, Nitin PAI <<a href="mailto:nitinmpai@gmail.com">nitinmpai@gmail.com</a>> wrote: > I am working on adding gstreamer support for our proprietary openmax > multimedia stack. So the best choice is to use gst-openmax pluggin. > I am facing problems with Audio Video Synchronization. > > Basically, > 1) How is startup AV sync handled in gst-openmax pluggin? There is a deep > pipeline in our audio stack. Just EmptyBufferDone call from audio sink > doesnt imply that the audio is played. This is handled via FirstAudioFrame > played event from the openmax core. > 2) How is AV sync done. I mean basically the decision to do video frame > drops or video frame hold? > > I will really appreciate some writeup on this. </div></div>Well, first of all, tunneling is not implemented yet in gst-openmax, there are some proposed patches but apparently some big changes are needed since GStreamer's base classes don't seem to consider these cases. Then there's the problem of A/V sync. This has been discussed in the past and the consensus is that the best way to implement this would be to map OpenMAX IL clock to GStreamer's clock. I don't have plans to implement this, so somebody else would need to do that. -- Felipe Contreras </blockquote></div> -- “Karmanya vadhikaraste ma phaleshu kadachana Ma karma-phala-hetur bhu ma te sango stav karmani” - Krishna