[gst-devel] Where'd the timestamps go?

[Tim-Philipp Müller]

On Thu, 2010-04-08 at 06:53 -0800, Wes Miller wrote:

> I have been using soaphttpsrc to gather a live mjpeg stream from an Axis
> camera server.  I use gst-launch to execute the capture and pipe it to 
> filesink with and without various muxings and demuxings etc.
>
> When I examine the file, even the rawest capture. there’s no timestamp
> information.  Where’d it go? 

Were there any timestamps to start with (at the GStreamer level)? In
general, you can look at timestamps of buffers passing through a
pipeline either by inserting an identity element into the pipeline, or
piping buffers into fakesink, and then passing the -v option to
gst-launch, e.g.:

 gst-launch-0.10 -v filesrc location=foo.mkv ! matroskademux ! fakesink

There should be timestamps at the container level. I don't think
GStreamer will use the date/time information you found for
synchronisation purposes. If you pipe jpegs into a 'raw' .mjpeg file
without any container, your timestamps are basically lost.

Cheers
 -Tim