[Vorbis-dev] Vorbis encoding bug on amd64

[Erik de Castro Lopo]

Hi all,

New bug entered in Trac:

    https://trac.xiph.org/ticket/1229

Description:

    I have a very simple floating point WAV file (mono, 2048 samples,
    16kHz sample rate) that gets really screwed up when encoded with 
    libvorbis on an amd64 CPU. The problem does not exist on ia32.

    The bug does exist both in SVN head and with oggenc v1.0.2 although 
    it isn't an oggenc bug because it manifests itself with using libogg/
    libvorbis/libvorbisenc directly.

    I'll attached the file (vorbis_enc_bug_on_amd64.wav) after submitting 
    the bug.

    Reproducing the bug with oggenc can be done as follows:

         oggenc vorbis_enc_bug_on_amd64.wav -o a.oga
         oggdec a.oga a.wav

    Now compare the original with WAV file with the output and you will 
    notice that the output has a bunch of grabage (noise) at the start of
    the file. I'll attach an image of input and output as well.

Cheers,
Erik
-- 
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Erik de Castro Lopo
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"Whenever the C++ language designers had two competing ideas as to
how they should solve some problem, they said, "OK, we'll do them
both". So the language is too baroque for my taste." -- Donald E Knuth