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Old 13 May 2007, 09:07 am   #1
andym00's Avatar
Join Date: Jan 2006
Posts: 3
Default psy.c: CalculateSMR ?

Just curious, but I've been following Musepack since it's original invocation, especially it's psychoacoustics and have always been a massive fan its results, and I've just noticed that the signal to mask ratio calculations have changed (significantly) since I last looked at it..

Can one of the developers explain to me why during signal to mask ratio calculations that the peak SMR discovered in a FFT resolution thresholds when find for each subband are now scaled by 1.44121959671885364405f ?
Previously, as far as I can see, it never used to inflate the SMRs like that, merely scaling by 0.0625f and which this additional scaling the bitrates seem overinflated.. Over inflated for a given NMT & TMN.. Maybe as much as 20%-30% increase in final bitrates..

Has in previous previous incarnations the psychoacoustics been miscalculated ? Or am I missing something here ?

I can't actually see when this change was made, but am very curious about it..
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