[vorbis] trying to get better ogg quality for this clip

John E. Leon Guerrero jlg2003feb at live365.com
Tue Feb 25 10:46:52 PST 2003



Yes, that sample sounds much better in the beginning since the "gravel 
effect" is gone and there is not much "swishing" in the guitar sound. 
However, IMHO, the rest of the piece sounds "flat" most likely due to 
the frequency limit.  For instance, with good headphones, you can hear 
the snare springs from under the snare drum in the other pieces when you 
A-B compare the samples.  Interestingly, the ogg samples that I provided 
earlier all sound wonderful in full 44khz after the initial 15 second 
intro.  For comparision sake, I encoded the sample with LAME at 64kbps, 
22khz, JS and found similar results.  Ie, the intro sounds good (though 
it doesn't have the same "bell-like" chiming quality that mp3 PRO and 
WMA have) due to the lack of the gravel effect and the swishing 
sound...but it too sounds flat for the rest of the sample which you can 
notice with the snare drum springs.

http://qa01.live365.com/jlg/VH_simple_64kb_22kh.mp3

I don't have a clue how hard this would be, but it would be wonderful if 
the encoder could tell that the first 15 seconds were going to be 
difficult to encode at 44khz and automatically downsample at 22khz 
(where it at least sounds normal despite lacking a little high end 
presence), and then resume the normal 44khz encoding once the "high 
demand" is over.  I noticed in winamp that the higher q settings 
consumed more bits-per-second for the opening piece, which could be an 
indicator.

thanks,
jlg

Tyler Knott wrote:
> http://webpages.charter.net/tknott/other/VH_simple-ABR64k.ogg

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