Getting played time in RTSP video

[Bruno Gonzalez]

I expect I cannot get duration, since the RTSP source can sometimes be live
video (unknown duration).
However, when I try to get the position, using a Query on my rtspsrc
element of the pipeline, I always get "-1" as result. I've tried using a
position query with bytes, buffers, time, percentage and everything, but
none returns a usable value.

Furthermore, the rtspsrc clock is not usable either, since it's just a
counter of time passed on the client side. So when playing at 2x, it
doesn't match the server time, nor does it account for jitter.

What can be influencing the queries to return -1? Am I doing something
wrong?

The code I'm using looks like this (using gstreamer-sharp):

Element rtspsrc = m_pipeline.GetByName("rtspsrc");
Query query = Query.NewPosition(Gst.Format.Time);
rtspsrc.Query(query);
long value;
Gst.Format format;
query.ParsePosition(out format, out value);
writeTrace("Query results: " + format + ", " + value);

Is that correct?

On Wed, Jan 25, 2012 at 10:07, Stefan Sauer <ensonic at hora-obscura.de> wrote:

> **
> On 01/24/2012 05:24 PM, Bruno Gonzalez wrote:
>
> Thanks for the input.
>
> Unfortunately, I still don't have any hints as to how to get the play time
> in the original source file.
>
>
> Use queries to get the duration and current playback position
>
> Stefan.
>
>
> Doing back-of-the-envelope calculations on the client is not an option, I
> need the actual playing time, with a precision of cents of second.
>
>  Any idea?
>
> On Tue, Jan 24, 2012 at 16:08, Stefan Sauer <ensonic at hora-obscura.de>wrote:
>
>>  On 01/24/2012 03:49 PM, Bruno Gonzalez wrote:
>>
>> Hi,
>>
>> I have a server-client video streaming using gstreamer and RTP. So
>> basically:
>> [source storage] --> [server] ---------> [client] --> [frames rendered
>> on screen]
>>
>> Is there any way to know, for each rendered frame, what was the
>> original playing time in the video source of the server?
>>
>> For example.
>>  - At 10 fps, after 30 seconds of playing, the "playing time" would be
>> 300.0 seconds.
>>  - But if the network is slow, the playing time could very well be
>> only 276.4 seconds.
>>  - Or maybe some frames could be lost if using UDP.
>>  - Also, if the source storage has variable framerate, I cannot use
>> "10fps" or any other average fps for any calculations.
>>
>>
>>  video is synchronized to the clock. That is after 30 sec of playing time
>> the video is more or less at 30s. If the network is slow, it is likely that
>> some frames have been skipped.
>>
>> Stefan
>>
>>
>> How could this be achieved?
>>
>> Thanks!
>>
>>  --
>> Saludos,
>>      Bruno González
>>
>> _______________________________________________
>> Jabber: stenyak AT gmail.com
>> http://www.stenyak.com
>>
>>
>> _______________________________________________
>> gstreamer-devel mailing listgstreamer-devel at lists.freedesktop.orghttp://lists.freedesktop.org/mailman/listinfo/gstreamer-devel
>>
>>
>>
>> _______________________________________________
>> gstreamer-devel mailing list
>> gstreamer-devel at lists.freedesktop.org
>> http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel
>>
>>
>
>
>  --
> Saludos,
>      Bruno González
>
> _______________________________________________
> Jabber: stenyak AT gmail.com
> http://www.stenyak.com
>
>
> _______________________________________________
> gstreamer-devel mailing listgstreamer-devel at lists.freedesktop.orghttp://lists.freedesktop.org/mailman/listinfo/gstreamer-devel
>
>
>
> _______________________________________________
> gstreamer-devel mailing list
> gstreamer-devel at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel
>
>


-- 
Saludos,
     Bruno González

_______________________________________________
Jabber: stenyak AT gmail.com
http://www.stenyak.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.freedesktop.org/archives/gstreamer-devel/attachments/20120126/e9cee651/attachment.htm>