[gstreamer-bugs] [Bug 346218] New: [audioresample] doesn't do anti aliasing

[GStreamer (bugzilla.gnome.org) <bug...@bu...>]

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 GStreamer | gst-plugins-base | Ver: 0.10.6

           Summary: [audioresample] doesn't do anti aliasing
           Product: GStreamer
           Version: 0.10.6
          Platform: Other
        OS/Version: All
            Status: UNCONFIRMED
          Severity: normal
          Priority: Normal
         Component: gst-plugins-base
        AssignedTo: gst...@li...
        ReportedBy: iv...@ab...
         QAContact: gst...@li...
     GNOME version: 2.11/2.12
   GNOME milestone: Unspecified


Please describe the problem:
I generate a 14khz tone with sampling rate of 44khz and resample it down =
to
22khz. I see there is a very high amplitude 8khz tone remaining in the ou=
tput
file.

The remaining 8khz tone is a total reflection of the 14khz tone (reflecte=
d
arround half the new sampling rate of 22khz)

Steps to reproduce:
1. gst-launch-0.10 audiotestsrc freq=3D14000 volume=3D0.6 num-buffers=3D5=
0 !=20
audio/x-raw-int, rate=3D(int)44100 ! wavenc ! filesink
location=3Dsine14k_at_44khz.wav
2. gst-launch-0.10 filesrc location=3Dsine14k_at_44khz.wav ! wavparse !
audioconvert ! audioresample ! audio/x-raw-int, rate=3D(int)22050 ! waven=
c !
filesink location=3Dconvert_14kat44khz_to_22khz.wav
3. check the output file with an audio editor (or play it)


Actual results:
There is aliasing in the output file.

Expected results:


Does this happen every time?
yes

Other information:


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