> On Aug 5, 2015, at 9:41 AM, Brian Willoughby <[email protected]> wrote: > > The two most common ways to depict audio waveforms are Peak and RMS. I don't > think there's any standard for displaying cube root - although I'm sure it > looks interesting. I'd recommend against inventing new math for displaying > audio waveforms, especially since there are well-established standards.
I think we’re talking about different things. Peak and RMS describe how to reduce a time range of a waveform to a single number. What I was referring to is how to transform that number (i.e. a raw amplitude) into a volume level that’s meaningful to a human, since our ears’ response to sound pressure is highly non-linear. I did some online searching and the two common approaches seem to be either logarithmic or cube-root. I experimented with both, and the latter seemed to produce a more intuitively-correct display, to me at least. (Disclaimer: I could be mis-remembering the formula; it’s been several years since I looked at my code for it.) —Jens
_______________________________________________ Do not post admin requests to the list. They will be ignored. Coreaudio-api mailing list ([email protected]) Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/coreaudio-api/archive%40mail-archive.com This email sent to [email protected]
