Both videomixer and glvideomixer do not want to work properly with avdec_h264 decoder

Submitted by Eugen Klim

Link to original bug (#779807)

Description

Hello. I want to build a graph which would mix pictures from a few h264 streams into one frame (so called ``picture in picture''). It seems that videomixer element is the right thing to do the trick. And videomixer works as expected with videotestsrc [graph_0.sh]. However, when I build graph with h264 decoder [graph_2.sh], it fails with an error:

ERROR: from element /GstPipeline:pipeline0/MpegTSParse2:mpegtsparse2-0: Internal data stream error.
Additional debug info:
mpegtsbase.c(1613): mpegts_base_loop (): /GstPipeline:pipeline0/MpegTSParse2:mpegtsparse2-0:
streaming stopped, reason not-negotiated (-4)

But when I switch videomixer with glvideomixer [graph_3.sh] it works fine. However, if I add background via videotestsrc, it also fails [graph_3b.sh].

Graph with decodebin and glvideomixer also works [graph_4.sh], but graph with decodebin, glvideomixer and videotestsrc background [graph_4b.sh] -- does not.

But I've noticed that [graph_4b.sh] works perfectly with mpeg2 decoded ts, while failing with h264 stream.

I could not understand what's the problem, but it seems that the problem is avdec_h264 related, so I need some help. I'm not sure is it a bug or am i doing something wrong.

I've attached graph scripts and 2 test streams (mpeg2 and h264).

Thank you.

Version: 1.10.x