[gstreamer-bugs] [Bug 449529] New: basetransform broken, not linking properly

[GStreamer (bugzilla.gnome.org)]

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  GStreamer | gstreamer (core) | Ver: 0.10.x
           Summary: basetransform broken, not linking properly
           Product: GStreamer
           Version: 0.10.x
          Platform: Other
        OS/Version: All
            Status: UNCONFIRMED
          Severity: normal
          Priority: Normal
         Component: gstreamer (core)
        AssignedTo: gstreamer-bugs at lists.sourceforge.net
        ReportedBy: spam at coreyo.net
         QAContact: gstreamer-bugs at lists.sourceforge.net
     GNOME version: 2.17/2.18
   GNOME milestone: Unspecified


Please describe the problem:
when there is no current peer, a pad template is returned with an ANY
capsfilter which is not necessarily the desired action.  This bug confirmed by
thaytan

I have included python code for two files in which I discovered this bug.  My
MetaDataDemuxer class will not link properly to the tee.  Linking it manually
fixes the problem.

Steps to reproduce:
I found this bug while working in python with the following 2 files:
#### metadata.py ###
import pygst
pygst.require('0.10')
import gst
import gobject
import time

# a constant so that we do not have to keep creating new caps
METADATA_CAPS = gst.caps_from_string('text/x-metadata')

# an object for encapsulating our video and metadata
class MetaData:

  def __init__(self, name="MetaData"):
    self.name = name
    self.data = {}
    self.fingerprints = {}

  def to_string(self):
    string = "name: %s\r\n" % str(self.name)
    for key, value in self.data.iteritems():
      string += "%s: %s\r\n" % (str(key), str(value))
    if len(self.fingerprints) > 0:
      for server, times in self.fingerprints.iteritems():
        entry, exit = times
        string += "fingerprint: %s, %s, %s\r\n" % (str(server), str(entry),
str(exit))
    string += "\r\n"
    return string

# the MetaDataInsertFilter element/plugin
class MetaDataInsertFilter(gst.Element):

  __gstdetails__ = ('MetaDataInsertFilter Plugin',
                    "metadata.py",
                    "Create Metadata to be pushed along with Buffers",
                    "Corey O.")


  _srcpadtemplate = gst.PadTemplate ("src",
                                     gst.PAD_SRC,
                                     gst.PAD_ALWAYS,
                                     gst.caps_new_any())

  _sinkpadtemplate = gst.PadTemplate ("sink",
                                      gst.PAD_SINK,
                                      gst.PAD_ALWAYS,
                                      gst.caps_new_any())

  __gsttemplates__ = (_srcpadtemplate, _sinkpadtemplate)

  def __init__(self):
    gst.Element.__init__(self)
    self.frame_count = 1
    self.srcpad = gst.Pad(self._srcpadtemplate)
    self.sinkpad = gst.Pad(self._sinkpadtemplate)
    self.add_pad(self.srcpad)
    self.add_pad(self.sinkpad)

    self.sinkpad.set_chain_function(self.chainfunc)
    self.sinkpad.set_event_function(self.eventfunc)

  def chainfunc(self, pad, buffer):
    metadata = MetaData()
    name = self.get_name()
    # remember to make the timestamp a proper string
    timestamp = repr(time.time())
    metadata.data['origin'] = name
    metadata.data['previous_node'] = name
    metadata.data['frame_count'] = self.frame_count 
    self.frame_count = self.frame_count + 1
    metadata.data['timestamp'] = timestamp
    if metadata.fingerprints.has_key(name):
      entry, exit = metadata.fingerprints[name]
    else:
      entry = '0.0'
    metadata.fingerprints[name] = [entry, timestamp]
    metadata_buffer = gst.Buffer(metadata.to_string())
    metadata_buffer.set_caps(METADATA_CAPS)
    self.srcpad.push(metadata_buffer)
    return self.srcpad.push(buffer)

  def eventfunc(self, pad, event):
    return self.srcpad.push_event(event)

# the MetaDataDemuxer element/plugin
class MetaDataDemuxer(gst.Element):

  __gstdetails__ = ('MetaDataDemuxer Plugin',
                    "metadata.py",
                    "Strip Metadata from Frames",
                    "Corey O.")

  _srcpadtemplate = gst.PadTemplate ("src",
                                     gst.PAD_SRC,
                                     gst.PAD_REQUEST,
                                     gst.caps_new_any())

  _metadatasrcpadtemplate = gst.PadTemplate ("metadatasrc",
                                             gst.PAD_SRC,
                                             gst.PAD_REQUEST,
                                             METADATA_CAPS)

  _sinkpadtemplate = gst.PadTemplate ("sink",
                                      gst.PAD_SINK,
                                      gst.PAD_ALWAYS,
                                      gst.caps_new_any())

  __gsttemplates__ = (_srcpadtemplate,
                      _metadatasrcpadtemplate,
                      _sinkpadtemplate)

  def __init__(self):
    gst.Element.__init__(self)
    self.srcpad = gst.Pad(self._srcpadtemplate)
    self.mdsrcpad = gst.Pad(self._metadatasrcpadtemplate)
    self.sinkpad = gst.Pad(self._sinkpadtemplate)
    self.add_pad(self.srcpad)
    self.add_pad(self.mdsrcpad)
    self.add_pad(self.sinkpad)

    self.sinkpad.set_chain_function(self.chainfunc)
    self.sinkpad.set_event_function(self.eventfunc)

  def chainfunc(self, pad, buffer):
    caps = buffer.get_caps()
    if caps == METADATA_CAPS:
      return self.mdsrcpad.push(buffer)
    else:
      return self.srcpad.push(buffer)

  def eventfunc(self, pad, event):
    return self.srcpad.push_event(event)

gobject.type_register(MetaDataInsertFilter)
gst.element_register(MetaDataInsertFilter, 'metadatainsertfilter')
gobject.type_register(MetaDataDemuxer)
gst.element_register(MetaDataDemuxer, 'metadatademux')

######## end file ############

####### test.py #######
#!/usr/bin/env python

import sys
import signal
import gobject

import pygst
pygst.require ("0.10")
import gst

import metadata
import mergemuxer

def main(args):
  pipeline = gst.parse_launch ("videotestsrc ! capsfilter
caps=video/x-raw-yuv,format=(fourcc)I420,width=(int)640,height=(int)480,framerate=(fraction)2/1
! metadatainsertfilter ! metadatademux ! tee name=t ! queue ! ffmpegcolorspace
! textoverlay text='<b>CAM1</b>' shaded-background=true ! ffmpegcolorspace !
xvimagesink")
  pipeline.set_state(gst.STATE_PLAYING)
  try:
    gobject.MainLoop().run()
  except KeyboardInterrupt:
    pipeline.set_state(gst.STATE_NULL)
    return 0
  return -1

if __name__ == '__main__':
  gobject.threads_init()
  sys.exit(main(sys.argv))


######### end file ########

Actual results:
failure to link two elements properly

Expected results:


Does this happen every time?
yes

Other information:


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