• Open Menu Close Menu
  • Apple
  • Shopping Bag
  • Apple
  • Mac
  • iPad
  • iPhone
  • Watch
  • TV
  • Music
  • Support
  • Search apple.com
  • Shopping Bag

Lists

Open Menu Close Menu
  • Terms and Conditions
  • Lists hosted on this site
  • Email the Postmaster
  • Tips for posting to public mailing lists
Latency and AUTimePitch
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Latency and AUTimePitch


  • Subject: Latency and AUTimePitch
  • From: Ashley Allen <email@hidden>
  • Date: Wed, 11 Jun 2008 17:36:12 -0700

Hi,

I submitted a question yesterday regarding AUTimePitch and latency.

Basically, I can create an AUGraph with AUFilePlayer units that successfully arranges and renders samples accurately with no gaps at the beginning or end of the file. In other words, if I want a 4 bar loop from my samples the rendered file is precisely 4 bars and timing is on point. All samples in this working scenario have the same beats per minute.

If I take the above AUGraph and add an AUTimePitch and AUFilePlayer unit to play a sample with a different beats per minute the timing is off. A latency is introduced by the AUTimePitch unit.  How do I compensate for this? All AUFilePlayers are on separate subgraphs that connect to an AUStereoMixer. Each subgraph ends with a genericOutputUnit. I tried setting the kAudioOutputUnitProperty_StartTimestampsAtZero on the genericOutputUnit which did not solve the problem. It's as if I have to prime the AUTimePitch unit. Is that possible?

I created another simple scenario of an AUGraph that contained an AUStereoMixer connected to a subgraph that contained an AUTimePitch unit and an AUFilePlayer. When I playback a single sample and render output to a file for a 4 bar loop, a gap starts at the beginning of the file which throws off the timing of the loop. If I take the AUTimePitch unit out, the gap at the beginning is gone and the timing is perfect. Is this gap a predictable offset that I can just chop off? What am I not getting?

Thanks in advanced ...


Ashley
 _______________________________________________
Do not post admin requests to the list. They will be ignored.
Coreaudio-api mailing list      (email@hidden)
Help/Unsubscribe/Update your Subscription:

This email sent to email@hidden

  • Follow-Ups:
    • Re: Latency and AUTimePitch
      • From: Jeremy Sagan <email@hidden>
  • Prev by Date: Re: Audio Device identification.
  • Next by Date: Re: Latency and AUTimePitch
  • Previous by thread: Re: Getting Started
  • Next by thread: Re: Latency and AUTimePitch
  • Index(es):
    • Date
    • Thread