[AUDITORY] equalPowerPanning on iOS

Subject: [AUDITORY] equalPowerPanning on iOS

From: "Picinali, Lorenzo" <l.picinali@xxxxxxxxxxxxxx>

Date: Sun, 9 May 2021 21:52:23 +0000

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Thread-topic: equalPowerPanning on iOS

Hello to everyone,

does anyone know what is the equation used in the equalPowerPanning algorithm on iOS (https://developer.apple.com/documentation/avfaudio/avaudio3dmixingrenderingalgorithm/equalpowerpanning?changes=_9)? The documentation doesn't really give much information ("An algorithm that pans the data of the mixer bus into a stereo field.") - what we are looking for is the formula that establishes the relationship between the panning value (-1 to 1) and the actual multiplier (0 to 1) for the left and right signals.

Let me know if you have an answer...otherwise we'll try to reverse engineer it, as Apple is very much closed source...

Thanks!
Lorenzo

--
Dr Lorenzo Picinali
Reader in Audio Experience Design
Dyson School of Design Engineering
Imperial College London
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