Changing the container format.

[Sameer Naik]

FYI,

I am using the latest releases of gstreamer.

flvdemux would not link to mpegtsmux because of the bytestream=avc on
the caps. To make it link it removed the caps bytestream property from
the flvdemux src caps.

Thanks and Regards
~Sameer

On Mon, Jun 6, 2011 at 6:58 PM, Sameer Naik
<sameer.subscriptions at damagehead.com> wrote:
> Hello,
>
> I am writing an application to change the container format of a media
> stream from flv -> mpegts, matroska, etc. I understand how i should go
> about building the pipeline i began testing sample pipelines using the
> very handy gst-launch utility.
>
> My input stream is an FLV file having h.264 video and mpeg2 audio. My
> ultimate task is to simply change the container format while keeping
> the encoded audio and video streams the same. So i constructed the
> pipeline as follows:
>
> gst-launch filesrc location=infile.flv ! flvdemux name=demux !
> video/x-h264 ! queue ! matroskamux name=mux ! queue ! filesink
> location=outfile.mkv  demux. ! audio/mpeg ! queue ! mux.
>
> This sample pipeline would not work and gst-launch is stuck at
> "pipeline is pre-rolling message". If i change the pipeline so that
> only one stream is contained within the container format, everything
> is file. i.e:
>
> gst-launch filesrc location=infile.flv ! flvdemux name=demux !
> video/x-h264 ! queue ! matroskamux name=mux ! queue ! filesink
> location=outfile.mkv
> OR
> gst-launch filesrc location=infile.flv ! flvdemux name=demux !
> audio/mpeg ! queue ! matroskamux name=mux ! queue ! filesink
> location=outfile.mkv
>
> The other multiplexers i tested with were, mpegtsmux and avimux. Each
> of these behave similarly.
>
> I went ahead and translated this pipeline into a gstreamer
> application. Here what i did:
>
> Create a pipeline with filesrc -> queue -> flvdemux  and an unlinked
> bin called encodebin with mpegtsmux -> queue -> udpsink
> I registered callbacks for the the pad-added and no-more-pads signals
> and set the pipeline to PAUSED state.
>
> Whenever a "pad-added" callback is called, a queue is added to the
> encodebin, linked to the mpegtsmux plugin. A ghost pad is added to the
> encodebin and the elements are linked.
>
> When no-more-pads signal is received is put the pipeline in the PLAYING state.
>
> But the application behave the same way as the gst-launch utility. If
> only one stream (audio/video) is linked in the "pad-added" callback
> then the application works. But if both audio and video are linked
> then the whole application just gets stuck. I tried, tried and tried a
> lot of things, nothing seems to work! Looks like i am making some huge
> mistake (can't figure it out though).
>
> I would like to know if i am missing something in the construction of
> the pipeline or not doing the right things.
> Any help would be greatly appreciated.
>
> Thanks and Regards
> ~Sameer
>