mp4mux complains about missing PTS

Florian Echtler floe at
Tue Apr 18 11:49:25 UTC 2023

Sure, will do! Which is the right place for reporting, though? Is it ?

Thanks and best, Florian

On 18.04.23 13:45, Sebastian Dröge wrote:
> On Tue, 2023-04-18 at 13:42 +0200, Florian Echtler via gstreamer-devel wrote:
>> I'm trying to record multiple H.264 and Opus streams to a MP4 file. However,
>> there is apparently some sort of race condition going on, because in roughly 8
>> out of 10 attempts, the pipeline fails with the following error and an EOS:
>> gst-stream-error-quark: Could not multiplex stream. (10):
>> ../gst/isomp4/gstqtmux.c(5402): gst_qt_mux_add_buffer ():
>> /GstPipeline:pipeline0/GstBin:bin_file_sink/GstMP4Mux:mux:
>> Buffer has no PTS.
>> In the other 20% of cases, the pipeline starts and the resulting MP4 file
>> contains all the streams, correctly synchronized and playable. I also tried with
>> qtmux instead of mp4mux, but got the same results.
>> I'm attaching the dot graph for the failure case; the dot graph for a successful
>> run looks exactly identical, with the only difference being that the filesink
>> doesn't flag EOS.
>> Side question: even if everything works, the resulting MP4 file is not seekable.
>> Is there a straightforward fix for that?
> Can you create an issue with this with a way to reproduce it?
> Most likely this is one of the known h264parse/baseparse PTS handling issues though.
> -- 
> Sebastian Dröge, Centricular Ltd · 
> <>


-------------- next part --------------
A non-text attachment was scrubbed...
Name: OpenPGP_signature
Type: application/pgp-signature
Size: 203 bytes
Desc: OpenPGP digital signature
URL: <>

More information about the gstreamer-devel mailing list