[opendtv] AVC for ATSC M/H

Found this on the JVT website.

http://ftp3.itu.ch/av-arch/jvt-site/2008_07_Hannover/AgendaWithNotesAB_d5.doc

http://ftp3.itu.ch/av-arch/jvt-site/2008_07_Hannover/JVT-AB016.zip

Ron

Liason Statment from ATSC:
The ATSC reported that it is developing specifications for a new service to deliver video to mobile and handheld devices, known as ATSC M/H. A tentative decision has reportedly been made to employ AVC coding, Baseline Profile at level 1.3, with one picture format of 416 by 240 luma samples (WQVGA), with frame rates from 12.0 to 30 fps. These choices were made based on input from device manufacturers who indicate they can support early market entry of a large number of receiving devices.
Broadcasters have reportedly expressed interest in transmitting higher resolution (up to wide SDTV) pictures over ATSC M/H. A tentative decision has also reportedly been made that higher resolution may be handled by use of SVC.
However, concerns have reportedly been expressed that by restricting the video tools that may be used (e.g. no 'B' frames), and relying on SVC as a path to higher resolution, some inefficiency may be designed in that could lead to a long term under-utilization of precious data bandwidth. Before decisions are final, broadcasters would reportedly like to better understand the consequences to eventual bit rate possibilities.
ATSC would welcome any information that MPEG could provide to them as to the possible increased efficiency (compared to Baseline Profile, Level 1.3, 416x240 pixel image format constrained for SVC) that could be obtained by choosing a set of AVC tools that would give us more efficient coding (e.g. use of 'B' frames, weighted prediction, directly coding wide SDTV vs using SVC, etc.).
ATSC would like to reference a specific MPEG AVC Profile in the M/H specification. If a set of AVC tools that do not fit within an existing AVC Profile are the best solution for the M/H application, they ask if MPEG would consider defining a new Profile that ATSC could reference in its standards. If such a new profile option would be considered, they ask in what time frame this work could be completed. 

Response from JVT:
Remark: It was suggested that the context of the intent was that picture aspect ratio would always be approximately 16:9, always have approximately square luma samples, and always be "progressive" scan. Further, it was suggested that the desire would be to have standardization completed in WG 11 and ATSC by the end of 2009, and to have devices actually deployed by that time. It was suggested that the total bit rate for the low-res and SD video might be about 0.5 Mbits/s. 

Basic aspects of contribution:

-        Interest in greater coding efficiency than Baseline
- Initial focus on 390-macroblock pictures, with longer term interest in SD 

-        Some interest in SVC

Suggestion: Respond saying:
The use of the High profile may be appropriate. Our understanding is that very low cost, low power decoder implementations of the High profile are already available in the marketplace. For example, we have located product announcements for High profile decoding such as: 

-        an implementation for 1920x1080p60 decoding that uses 160 mW,

-        an implementation quoting 1080p using 120 mW,
- a reference to 3.5G and 4G mobile implementations of high bit rate High profile 1080p decoding in 2009-2011, 

-        an announcement referring to HD decoding using 45mW,
Further such information should be discoverable with somewhat more study. Note that support for 1920x1080p60 would include support for a sample processing speed ratio that is higher by a factor of more than 40 relative to the requirements for 416x240x30.
Regarding compression capability, some information that we have received suggests that about a 40-60% bit rate savings for use of High profile rather than Baseline profile might be expected for material such as the 416x240 use that they describe (e.g., per JVT-N014 of Jan 2005, and we note that encoding technology for use of High profile features has advanced substantially further since that time).
If the High profile does not meet the needs of your application, we are prepared to collaborate further with you to study the subject and take appropriate action as necessary. Although we suggest that no new profile specification should be needed, in the event that this initial assessment is incorrect, the ISO/IEC approval process (and typical parallel ITU-T approval processing) for a new profile specification would ordinarily take 1-1.5 years after the decision to create a new profile and the determination of the detailed requirements of the profile design.
Selection of the High profile for lower resolution use would not preclude the use of scalable video coding (SVC) with this lower resolution video as the base layer, as the AVC specification includes a Scalable High profile that is specified to operated in that fashion.
We encourage further study and communication regarding the detailed application requirements, such as bit rates, image sizes, frame rates, etc. for the combined usage scenarios for the SD delivery in conjunction with WQVGA over ATSC M/H.

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