MTAudioProcessingTap - The Pre and Post effect MTAudioProcessingTapCreationFlags
Q:
MTAudioProcessingTapCreate
allows you to pass in some MTAudioProcessingTapCreationFlags
flags designating if you want the tap inserted Pre or Post Effect. What does this mean?
A: The MTAudioProcessingTap
object is always used with a AVAudioMix
object and its array of instances of AVAudioMixInputParameters
. You associate a MTAudioProcessingTapRef
with a track using the AVMutableAudioMixInputParameters
audioTapProcessor
property as shown in Figure 1.
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When you create a "pre-effects" audio tap using the kMTAudioProcessingTapCreationFlag_PreEffects
flag, the tap will be called before any effects specified by AVAudioMixInputParameters
are applied; when you create a "post-effects" tap by using the kMTAudioProcessingTapCreationFlag_PostEffects
flag, the tap will be called after those effects are applied. Currently the only "effect" that AVAudioMixInputParameters
supports is a linear volume ramp.
Document Revision History
Date | Notes |
---|---|
2013-03-11 | New document that discusses the flags used when creating audio processing taps. |
Copyright © 2013 Apple Inc. All Rights Reserved. Terms of Use | Privacy Policy | Updated: 2013-03-11