• 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
iPhone SW Decoding Performance of MP3 vs AAC
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

iPhone SW Decoding Performance of MP3 vs AAC


  • Subject: iPhone SW Decoding Performance of MP3 vs AAC
  • From: McD <email@hidden>
  • Date: Thu, 8 Apr 2010 01:57:53 -0700 (PDT)

Hello All,
I am doing some iPhone OS performance testing of various audio formats.  My understanding is that AAC should be more efficient than MP3 for SW decoding.  However, my results seem to indicate the opposite.  For my testing I am using the Ambient Audio Session Category to ensure that decoding is done in software.  I wrote a basic app that does nothing but use AVAudioPlayer to play file a 2:53 file for 42 seconds and then stop it.  I am getting 0.79-0.92 CPU time for AAC encoding and 0.65-0.68 for the mp3 encoding.  This result indicates the opposite of what I've read is correct.  Is comparing the CPU time a valid way of comparing performance?  If so, how can these results be explained?  I am using an iPod Touch 2nd Gen with iPhone OS 3.0.

Regards,
Paul

 _______________________________________________
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: iPhone SW Decoding Performance of MP3 vs AAC
      • From: James McCartney <email@hidden>
    • Re: iPhone SW Decoding Performance of MP3 vs AAC
      • From: Massimiliano Leggieri <email@hidden>
  • Prev by Date: Local playback
  • Next by Date: Re: iPhone SW Decoding Performance of MP3 vs AAC
  • Previous by thread: Local playback
  • Next by thread: Re: iPhone SW Decoding Performance of MP3 vs AAC
  • Index(es):
    • Date
    • Thread