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<div class="moz-cite-prefix">On 05/30/2015 07:39 AM, Luis de
Bethencourt wrote:<br>
</div>
<blockquote
cite="mid:CAPA4HGVVY2pium+NpUe9-ogM=G1RL7z652ebF3isWcttSmu3GA@mail.gmail.com"
type="cite">
<div dir="ltr">On 30 May 2015 at 06:14, Dustin Spicuzza <span
dir="ltr"><<a moz-do-not-send="true"
href="mailto:dustin@virtualroadside.com" target="_blank">dustin@virtualroadside.com</a>></span>
wrote:<br>
<div class="gmail_extra">
<div class="gmail_quote">
<blockquote class="gmail_quote" style="margin:0px 0px 0px
0.8ex;border-left:1px solid
rgb(204,204,204);padding-left:1ex">Hey,<br>
<br>
I'm using GStreamer 1.4.5 on Fedora 21 via gst-python.<br>
<br>
I'm embedding playbin elements inside of another pipeline,
with the goal<br>
to use multiple playbins to play multiple files
simultaneously and feed<br>
them to the same output via an adder -- that part actually
works, and I<br>
can play two audio streams at once. So far so good.<br>
<br>
However, after I start the pipeline, I've found that I'm
having problems<br>
stopping it, and it deadlocks.<br>
<br>
PLAYING -> NULL: I did find that if I set the playbin
state to NULL<br>
before setting its parent's state to NULL, then it doesn't
deadlock.<br>
However, this leads me to believe I'm missing something
here, as I<br>
should only need to set the pipe to NULL and not the
playbin too, right?<br>
<br>
PAUSED -> NULL: I don't know how to break this
deadlock, I'm sure it's<br>
something simple I'm missing. It looks like the thread is
blocked on a<br>
pad lock (gstpad.c:966 - gst_pad_activate_mode) on the
GhostPad I<br>
created to connect the playbin to the adder. Using GDB,
the owner of the<br>
lock is the PulseSink thread, who is waiting for something
to happen at<br>
gst_base_sink_wait_preroll() -- gstbasesink.c:2151.<br>
<br>
I've posted a very short python implementation that
demonstrates the<br>
problem with a single playbin at github:<br>
<a moz-do-not-send="true"
href="https://gist.github.com/virtuald/7592a16d6dee07404438"
target="_blank">https://gist.github.com/virtuald/7592a16d6dee07404438</a><br>
<br>
Thanks for any assistance!<br>
<br>
Dustin<br>
</blockquote>
<div><br>
</div>
<div>Hello Dustin,<br>
<br>
</div>
<div>I run your Python code and it works with current
GStreamer from git. I can't reproduce your deadlock.<br>
<br>
</div>
<div>Could you provide a debug log? [0]<br>
<br>
</div>
<div>Also, in your case I think it would be better if you
used filesrc and decodebin, instead of playbin.<br>
<br>
</div>
<div>I am not very clear on what is the purpose of the Bin
you create. What is it for?<br>
<br>
</div>
<div>Thanks,<br>
</div>
<div>Luis<br>
<br>
[0] <a moz-do-not-send="true"
href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gst-running.html">http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/gst-running.html</a></div>
</div>
</div>
</div>
</blockquote>
<br>
Thanks for trying this out Luis. That's unfortunate that it works
with the latest git. <br>
<br>
playbin has 5000+ lines of time-tested code that binds
filesrc/decodebin together, among other things. Why would I try to
duplicate that effort by creating my own filesrc/decodebin/etc?<br>
<br>
The 'pipe' pipeline element is created so that every element can
have a common parent. Gstreamer doesn't seem to like it if I try to
connect elements that don't have common parents.<br>
<br>
The 'out1' bin element is created so that I can set the 'audio-sink'
property of the playbin, which connects playbin to the adder via the
proxy GhostPad. It was the easiest way I could see to get output
from the playbin.<br>
<br>
The goal is to have multiple playbin elements taking care of
decoding/etc, and hook them all up to the adder and output to a
single stream -- and dynamically add/remove the playbins and vary
their volumes independently.<br>
<br>
I've added a log to the original gist via:<br>
<br>
GST_DEBUG_NO_COLOR=1 GST_DEBUG=4 GST_DEBUG_FILE=debug.log python
test.py<br>
<br>
<a moz-do-not-send="true"
href="https://gist.github.com/virtuald/7592a16d6dee07404438"
target="_blank">https://gist.github.com/virtuald/7592a16d6dee07404438</a><br>
<br>
Thanks so much!<br>
<br>
Dustin<br>
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