[opendtv] Re: DVB considers SVC for 1080p and hierarchical modulation

  • From: Albert Manfredi <albert.e.manfredi@xxxxxxxxxx>
  • To: <opendtv@xxxxxxxxxxxxx>
  • Date: Wed, 10 Dec 2008 21:06:28 -0500

Tom Barry wrote:
 
> Will ATSC M/H even have enough throughput for a single
> decent 720p stream after error correction?
 
That's a bit like asking whether ATSC can handle H.264. Lots of people swore it 
couldn't, but they were wrong. Standards can always be amended, and adding 
H.264 was a fairly obvious possibility right from the start.
 
One possibility here is if M/H can be used without the extra FEC. Just for its 
extra training or for use with SFN towers, as A-VSB allowed. If it can be made 
to do that, and you dedicate the entire channel to M/H, then in principle you 
should be able to support HDTV without any trouble.
 
Another possibility is if you dedicate the entire channel to M/H and use 1/2 
rate FEC. IN PRINCIPLE, that gives you approximately 9 Mb/s capacity, which IN 
PRINCIPLE is enough for 720 at 24p, even with MPEG-2 compression.
 
I'll bet the standard will artifically limit how much of the channel can use 
M/H, just like E-VSB does. That's just penmanship, though. It would be 
inconceivable for receivers to police that rule, if there were such a rule. So 
all it would take is someone to amend a paragraph or so, and that's that.
 
Bert
 
_________________________________________________________________
Send e-mail faster without improving your typing skills.
http://windowslive.com/Explore/hotmail?ocid=TXT_TAGLM_WL_hotmail_acq_speed_122008
 
 
----------------------------------------------------------------------
You can UNSUBSCRIBE from the OpenDTV list in two ways:

- Using the UNSUBSCRIBE command in your user configuration settings at 
FreeLists.org 

- By sending a message to: opendtv-request@xxxxxxxxxxxxx with the word 
unsubscribe in the subject line.

Other related posts: