[ogg-dev] Using oggCat

[Brian Rayne]

Hi, folks.  I'm trying to prepend an OGG file with a given amount of
silence.  The solution that another developer and I are working with is to
generate an audio file of a given duration of silence, convert that to OGG
and use oggCat to try to append them.

This does work, however I'm seeing that in Windows, oggCat is seems to be
re-encoding the audio (it counts from 0 to what I assume is the number of
seconds of audio in the resulting file, taking a couple minutes, which is
how long it would take to encode the audio in question).  We've tried
various things to ensure that the 2 OGG files are similar enough to be able
to be concatenated without re-encoding, such as:  Encoding a full song to
OGG (in stereo, 192Kbps bit rate, 44.1KHz sample rate) using oggenc2 (a
command line OGG encoder), creating a WAV file containing nothing but
silence, reading the OGG's reported nominal bitrate (using the Vorbis API's
vorbis_info structure) and encoding the WAV file to OGG (using the first OGG
file's sample rate and nominal bit rate).  Once both OGGs are created, when
I use oggCat, it will still re-encode instead of doing a quick
concatenation.

The other developer I'm working with says that when he does the same
procedure in a *nix environment, it does not re-encode the audio.  This is
even though he is using the same methods that I am using in a Windows
environment.

Can anybody determine if this is a bug?  Or would somebody be willing to
test oggCat by appending these two files together (file 1, then file 2) to
see if oggCat is behaving different in Windows versus *nix, or if the files
are somehow being created in some incompatible manner?  The files in
question are here:
http://www.sendspace.com/file/e3krsr

Unless we can get oggCat to work as expected in our cross platform
application, we won't be able to use it reliably.  Thank you for any help
you can provide.
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