Pluggable Bin

Tim Müller tim at
Fri Feb 21 09:08:49 PST 2014

On Fri, 2014-02-21 at 08:33 -0800, MartinK wrote:

Hi Martin,

> I have tried to create a Pluggable bin element which, at the moment,
> is just a bin containing two NullFilter elements linked together. A
> NullFilter is a raw video filter which simply copies input to output.
> The NullFilter itself has been tested and works. Also, the
> PluginLoader is tested and works. The test pipeline works if
> PluggableBin is replaced by NullFilter. However, the PluggableBin
> fails with the following messages: Pipeline is PREROLLING ... ERROR:
> from element /GstPipeline:pipeline0/GstVideoTestSrc:videotestsrc0:
> Internal data flow error. Additional debug info: gstbasesrc.c(2625):
> gst_base_src_loop
> (): /GstPipeline:pipeline0/GstVideoTestSrc:videotestsrc0: streaming
> task paused, reason not-linked (-1) ERROR: pipeline doesn't want to
> preroll. Links to the sources and test pipeline are given below. Is
> anyone able to shed any light on what might be wrong?

Maybe make a GST_DEBUG=*:6 log and grep for not-linked to see where the
problem is?

in the PluggableBin's init function, perhaps try gst_bin_add()ing the
null filter elements before you create the ghost pads. I'm not sure if
the target pad will be set right if it's not yet inside the bin


Tim Müller, Centricular Ltd -

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