[vorbis-dev] Major quality decrease in RC3 compared to RC2

[Sven Over]

Hello...

I was very surprised when I found, that oggfiles created with RC3 are much 
worse than files made with RC2.

I have some example sound file set up for you on the net. The difference is 
*obvious*. While RC2 made ogg-files, which I would say are perfect (at least 
I cannot hear a difference to the original), the quality of RC3 is *bad*.

Let me first say, that I used libvorbis0, libogg0 and vorbis-tools Debian 
packages. After I discovered the quality decrease, I compiled the libraries 
and vorbis-tools from source, both using gcc 2.95.4 and gcc 3.0.3, each of 
which gave the same result: bad quality.

Here's the proof:

Original WAV-File (~5MB)
 http://stud.physik.uni-dortmund.de/~svenor/joy.wav
Same as FLAC-File (~3.5 MB)
 http://stud.physik.uni-dortmund.de/~svenor/joy.flac
And as MP3 with very high quality and bitrate (~1MB) - I think this is okay 
for comparison so that you do not need to download one of the above
 http://stud.physik.uni-dortmund.de/~svenor/joy.mp3

The ogg files:
Made with RC2 (perfect result)
 http://stud.physik.uni-dortmund.de/~svenor/joy_oggrc2.ogg
Made with RC3 (crap, simply speaking)
 http://stud.physik.uni-dortmund.de/~svenor/joy_oggrc3.ogg

I used the following command line to generate the oggs:
oggenc -b 128 -o joy_oggrc2.ogg joy.wav
oggenc -b 128 -o joy_oggrc3.ogg joy.wav

...for creating the mp3 file I used:
lame --abr 256 -q 0 joy.wav joy.mp3

I think here is some bug involved. Same command line should not produce a 
result with RC3 that is so much worse than with RC2. Believe me, the quality 
of RC3 here is really *bad*. Download my sample files, try to create your own 
oggs from them. (Of course, I used the .wav-file for generation. As FLAC is 
lossless, you can make the wav from the FLAC file.)

Please! Find that bug!

Ogg is such a great codec, I was just going to render my hole cd collection 
to ogg instead of mp3. In fact, I already begun. Thank you all for that great 
great work. But the quality of RC3 here is inacceptable, sorry.

Thanx in advance! Good luck!


-- 
Sven Over
An der Stipskuhle 42                     svenover at svenover.de
44141 Dortmund          svenor at student.physik.uni-dortmund.de
Telefon: 0231-5648658                 http://www.svenover.de/

PGP: Public-Key-ID: F56F17C6                     Fingerprint:
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