[gstreamer-bugs] [Bug 580952] New: audioconvert/audioresample bad quality compared to plughw

[GStreamer (bugzilla.gnome.org)]

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  GStreamer | gst-plugins-base | Ver: 0.10.22
           Summary: audioconvert/audioresample bad quality compared to
                    plughw
           Product: GStreamer
           Version: 0.10.22
          Platform: Other
        OS/Version: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: Normal
         Component: gst-plugins-base
        AssignedTo: gstreamer-bugs at lists.sourceforge.net
        ReportedBy: justin at affinix.com
         QAContact: gstreamer-bugs at lists.sourceforge.net
     GNOME version: Unspecified
   GNOME milestone: Unspecified


On my machine, this produces a tone as normal:

gst-launch-0.10 audiotestsrc ! 'audio/x-raw-int,rate=16000,width=16,channels=1'
! alsasink device=plughw:0,0

And this produces a tone full of pops:

gst-launch-0.10 audiotestsrc ! 'audio/x-raw-int,rate=16000,width=16,channels=1'
! audioconvert ! audioresample ! alsasink device=hw:0,0

The first command lets ALSA do the format conversion, and sounds good.  The
second command uses audioconvert/audioresample to do the format conversion
(which according to verbose output turns out to be
'audio/x-raw-int,rate=44100,width=32,channels=2'), and sounds bad.

This is also full of pops:

gst-launch-0.10 audiotestsrc ! 'audio/x-raw-int,rate=16000,width=16,channels=1'
! audioconvert ! audioresample !
'audio/x-raw-int,rate=44100,width=32,channels=2' ! alsasink device=plughw:0,0

This third command shows that the problem is probably not an issue with hw vs
plughw, but the mere use of audioconvert/audioresample.

I /think/ the bug is in audioresample.  Testing with legacyresample seems to
make the pops go away.


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