[gst-devel] Totem, Gst-Player, libgstplay showstoppers

[Julien MOUTTE]

Hi guys,

Here is a list of show stoppers for audio/video playback in the gnome
desktop. If by any chance some core hackers want to dedicate some time
helping in the gnome interaction direction this is the todo list...

Here is the gstplay pipeline :
http://getcontrol.sourceforge.net/files/gstplay_pipeline.png

1) This pipeline uses switch to have both visualization and video output
of spider connected to the video sink while waiting for identity to tell
if there's video in the pipeline. If video is detected, visualization is
then disconnected. That works just fine. The issue is that if no video
output comes out from spider then video_queue is empty and switch tries
to gst_pad_pull from that pad which locks forever. So audio playback is
broken with visualization enabled.

Proposed solutions :
 a) Use gst_pad_select to get buffers only from pads that provides some
in switch.
 b) Make gst_pad_pull timeout somehow and let switch knows so that it's
not pulling for nothing there.
 c) Make switch chain based so that buffers are pushed to it.

2) Seeking is completely broken, both for audio only and video files.
That's really a critical bug and we have to get that fixed ASAP !

Proposed solutions :
 a) Find when that has been broken. IIRC it was working before caps
merge.
 b) Write down how seeking should work and check that it's implemented
correctly.

3) Tagged audio files are making problems in spider. Benjamin keeps
repeating that the gstplay pipeline is hard to debug. Well i can
understand that but still we should be able to debug why spider is not
playing those medias.

Proposed solutions :
 a) Attach benjamin on a chair with a gst-debug-log-level=5 under the
eyes so that he can fix spider to play those files.
 b) Enforce a) somehow ;-)

4) Informations about codecs. xine provides the app developer with some
informations about video/audio codecs. I need to get those informations
from gstplay pipeline to compete with them.

Proposed solutions :
 a) Add some gst_element_found_tags calls in decoders so that they tell
about the codec format they are about to decode.
 b) Add some gst_element_found_tags calls in demuxers so that they tell
about the different format of video/audio...
 c) Invent a new communication system/signal for that kind of stuff.

That's all for today. If i have some more coming out of my head i ll
mail again.

Julien,

-- 
Julien MOUTTE (aka Dolphy)

Homepage : http://dolphy-tech.net
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