[gst-devel] caps negotiation problem with audioconvert

Steve Fink sphink at gmail.com
Tue Sep 4 23:15:17 CEST 2007

I ran into this error message with the element I am (slowly, badly)
attempting to write, and I was able to reproduce it with a builtin

% gst-launch-0.10 -v filesrc location=ping.wav ! volume ! audioconvert
! fakesink
Setting pipeline to PAUSED ...
Pipeline is PREROLLING ...
/pipeline0/fakesink0: last-message = "event   ******* E (type: 102,
GstEventNewsegment, update=(boolean)false, rate=(double)1,
applied_rate=(double)1, format=(GstFormat)GST_FORMAT_BYTES,
start=(gint64)0, stop=(gint64)39212, position=(gint64)0) 0x9489608"
ERROR: from element /pipeline0/volume0: not negotiated
Additional debug info:
gstbasetransform.c(1498): gst_base_transform_handle_buffer ():
not negotiated
ERROR: pipeline doesn't want to preroll.
Setting pipeline to NULL ...
FREEING pipeline ...

I'm assuming the problem is between volume and audioconvert -- they
haven't agreed on a set of caps. But they're both based on
gst_base_transform, which looks like it at least intends to do the
right thing.

gst-inspect volume:

Plugin Details:
  Name:                 volume
  Description:          plugin for controlling audio volume
  Filename:             /usr/lib/gstreamer-0.10/libgstvolume.so
  Version:              0.10.12

gst-inspect audioconvert:

Plugin Details:
  Name:                 audioconvert
  Description:          Convert audio to different formats
  Filename:             /usr/lib/gstreamer-0.10/libgstaudioconvert.so
  Version:              0.10.12

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