interleave: Does not handle request pad names correctly
Submitted by Yasushi SHOJI
Link to original bug (#708988)
Description
Created attachment 255977
GST_DEBUG=4 GST_DEBUG_NO_COLOR=1 gst-launch-1.0 interleave name=i ! pulsesink audiotestsrc ! i.sink_0 audiotestsrc wave=red-noise ! i.sink_1
It seems to me that the interleave module example on the current documentation[1] does not work. The command line example is this:
gst-launch-1.0 interleave name=i ! audioconvert ! wavenc ! filesink location=file.wav filesrc location=file1.wav ! decodebin ! audioconvert ! "audio/x-raw,channels=1" ! queue ! i.sink_0 filesrc location=file2.wav ! decodebin ! audioconvert ! "audio/x-raw,channels=1" ! queue ! i.sink_1
It is very long so I've modified to shorten it to this:
gst-launch-1.0 interleave name=i ! pulsesink \
audiotestsrc ! audio/x-raw,channels=1 ! i.sink_0 \
audiotestsrc wave=red-noise ! audio/x-raw,channels=1 ! i.sink_1
Both example failed to run with an error message:
WARNING: erroneous pipeline: could not link audiotestsrc0 to i
slomo on the GStreamer IRC channel told me that the "problem is that interleave does not take the requested pad name into account... so the second chain requests "sink_1" but gets "sink_0", and the other way around".
To back up his comment, I've taken a debug message to see what it says (Full log attached). Here is the excerpt that I think relevant:
The second chain (sink_1) request:
GST_ELEMENT_PADS gstutils.c:1543:gst_element_link_pads_full: trying to link element capsfilter0:src to element i:sink_1
GST_ELEMENT_PADS gstelement.c:897:gst_element_get_static_pad: found pad capsfilter0:src
GST_ELEMENT_PADS gstelement.c:894:gst_element_get_static_pad: no such pad 'sink_1' in element "i"
GST_ELEMENT_PADS gstelement.c:894:gst_element_get_static_pad: no such pad 'sink_1' in element "i"
GST_ELEMENT_PADS gstelement.c:646:gst_element_add_pad:<i> adding pad 'sink_0'
GST_PADS gstutils.c:1443:prepare_link_maybe_ghosting: capsfilter0 and i in same bin, no need for ghost pads
GST_PADS gstpad.c:2083:gst_pad_link_prepare: trying to link capsfilter0gst_pad_link_prepare: trying to link capsfilter0:src and i:sink_0
GST_PADS gstpad.c:2285:gst_pad_link_full: linked capsfilter0:src and i:sink_0, successful
As you can see that the sink_1 reqest ended up linking to sink_0. Pipleline creation continue to the first chain (sink_0) request:
GST_ELEMENT_PADS gstutils.c:1543:gst_element_link_pads_full: trying to link element capsfilter1:src to element i:sink_0
GST_ELEMENT_PADS gstelement.c:897:gst_element_get_static_pad: found pad capsfilter1:src
GST_ELEMENT_PADS gstelement.c:897:gst_element_get_static_pad: found pad i:sink_0
default gstutils.c:1877:gst_element_link_pads_filtered: Could not link pads: capsfilter:src - i:sink_0
and failed.
Attachment 255977, "GST_DEBUG=4 GST_DEBUG_NO_COLOR=1 gst-launch-1.0 interleave name=i ! pulsesink audiotestsrc ! i.sink_0 audiotestsrc wave=red-noise ! i.sink_1":
log.txt