International organisation for standardisation

Level	AOT of Core Coder	Max. number output channels	Max. sampling rate[kHz]	MPS
Max. PCU
1	ER AAC (E)LD	1.0	48	n/a	5
2	ER AAC (E)LD	2.0	48	LD MPS 2-1-2	11.5
3	ER AAC (E)LD	5.1	48	LD MPS 2-1-2	30
4	ER AAC (E)LD	5.1	48	LD MPS 5-x-5	30

The profile has significant industry support, as shown here:

• 
  British Telecommunications plc
  
• 
  Cisco Systems, Inc.
  
• 
  Comrex Corporation
  
• 
  Fraunhofer IIS
  
• 
  Lifesize
  
• 
  MAYAH Communications GmbH
  
• 
  Philips
  
• 
  The Telos Alliance
  

David Singer, Apple, noted that many customers of this profile may not need the error resilience tools provided by the AOT’s in the profile. He wondered whether the companies listed as supporting the profile will use the profile over bit-error-prone communication channels (as opposed to packet networks).

Abdellatif Benjelloun Touimi, Hauwei, asked whether there is any subjective performance test data for the profile configuration.

Gregory Pallone, Orange Labs, expressed support for the profile, but agreed that subjective performance test data for the profile is important and, furthermore, that test bitstreams, decoders and decoded files should be made available.

Heiko Purnhagen, noted that document N16973 (Xian) provides subjective test results for

• 
  ER AAC ELD stereo at 32 kb/s and 48 kb/s
  
• 
  ER AAC ELD + LD MPS 212 at 32 kb/s
  
• 
  ER AAC ELD + MPS 525 at 128 kb/s + MPS payload
  
• 
  ER AAC ELD + LD MPS 525 at 128 kb/s + MPS payload
  

With respect to timeline, the Chair noted that this profile could be adopted into ISO/IEC 14496-3:2009/PDAM 3 Transport of Unified Speech and Audio Coding which progresses to FPDAM at this meeting.

David Singer, Apple, noted that an additional profile could restrict bitstreams (i.e. encoder behaviour) such that the implementation complexity of the profile is reduced for the second profile. It was agreed that this issue can be studied during the FPDAM ballot interval and NBs can provide input via ballot comments.

Jeff Huang, Qualcomm, asked whether there should be subjective quality tests for the profile operating over packet networks. Bernhard Grill, FhG, noted that the AAC-LD family does not have any inter-frame memory and so is very robust to packet losses.