International organisation for standardisation organisation internationale de normalisation

2.3Creation of Task Groups

Task groups were convened for the duration of the MPEG meeting, as shown in . Results of task group activities are reported below.

2.4Approval of previous meeting report

The 87^th Audio Subgroup meeting report was registered as a contribution, and was approved.

2.5Review of AHG reports

There were no requests to review any of the AHG reports.

2.6Joint meetings

There were no joint meetings.

Groups

What

Where

Day

Time

2.7Received National Body Comments and Liaison matters

The NB Comments and Liaison documents for the meeting that require a response are as shown below.

No.	From	Title	Response
m16297	Swedish NB via SC 29 Secretariat	Swedish NB comment in response to Resolution 3.1.2 in N10312	Kjörling
m16343	IEC TC 100	IEC CDV 62571: Digital Audiobook File Format and Player Requirements [IEC 100/1543/CDV]	Quackenbush
M16467	EBU	Liaison Statement from EBU [SC 29 N 10254]	No response
m16476	DRM	Audio Liaison Statement from DRM [SC 29 N 10255]	No response
m16477	WorldDMB Forum	Audio Liaison Statement from WorldDMB Forum [SC 29 N 10256]	No response
m16491	3GPP	Liaison Statement from 3GPP SA4	No response

2.8Plenary Discussion

2.8.1Profiles and 960/1024 transform lengths

Kristofer Kjörling, Dolby, presented

m16297

Swedish NB comment in response to Resolution 3.1.2 in N10312

Swedish NB via SC 29 Secretariat

The group then reviewed the following Liaison contributions:

m16467	EBU	Liaison Statement from EBU [SC 29 N 10254]
m16476	DRM	Audio Liaison Statement from DRM [SC 29 N 10255]
m16477	WorldDMB Forum	Audio Liaison Statement from WorldDMB Forum [SC 29 N 10256]
M16491	3GPP	Liaison Statement from 3GPP SA4

The Liaisons can be summarized as:

EBU requires that 960 continue to be supported in the MPEG specifications. The best long-term solution would to be for devices to support both 960 and 1024. However, they concede that since many devices implement only 1024, a restricted set of profiles might be appropriate.

DRM specifies MPEG-4 AAC with SBR and PS with 960 in combination with MPEG-4 Error Resilience bitstream format. The best long-term solution would to be for devices to support both 960 and 1024.

WorldDMB notes that one of its systems specifies HE-AAC V2 at 960 while another specifies HE-AAC V2 at 1024. The best long-term solution would to be for devices to support both 960 and 1024.

3GPP only mandates 1024 in their aacPlus specifications. They are not impacted by whether or not 960 is mandated in an MPEG profile.

Discussion

Yuriy Resnik, Qualcomm, noted that the Liaison referenced only one of several 3GPP specifications.

One proposal for going forward is to:

• 
  No longer mandate support for 960 in AAC, HE-AAC and HE-AAC V2 profiles.
  
• 
  Create a new profile “AAC Grand Alliance” that is a single profile that mandates AAC, SBR and PS tools that operate at 960 and 1024 transform lengths.
  

Ralph Sperschneider, FhG, noted that the latter profile is exactly the HE-AAC V2 profile. Yuriy Reznik, Qualcomm, noted that 3GPP2 references MPEG-4 AAC profile and MPEG-4 HE-AAC profile (3gpp2 C.S0046-0 and C.S0045-A).