[opendtv] Re: Let the games begin
- From: "Manfredi, Albert E" <albert.e.manfredi@xxxxxxxxxx>
- To: <opendtv@xxxxxxxxxxxxx>
- Date: Mon, 13 Nov 2006 11:23:47 -0500
Craig Birkmaier wrote:
> NO. HDTV was fully defined in the DVB standards from day one.
> MPEG-4 is an addition, but it fits with NO OTHER CHANGES to
> the standard.
So, identical to ATSC as of 1995, when the SD options were added. Both
schemes can add AVC without making "any other changes," as you call it.
> This IS NOT as A-VSB it to ATSC. A-VSB is a completely new
> modulation scheme that happens to be backward compatible to
> 8-VSB (i.e. it does not break legacy receivers).
What leads to to labor under this misconception, Craig? What is
"completely new" about A-VSB?
The "modulation" is IDENTICAL to 8-VSB. It *is* 8-VSB. You may have
missed the fact that A-VSB, just like E8-VSB, does NOT add any different
modulation types. There is no 2-VSB or 4-VSB, QAM, or anything else.
Instead, the difference is in how some of the payload is being used to
assist in training. And the addition of turbo codes as an extra add-on
convolutional FEC scheme.
I repeat: much like the Chinese did when they modified COFDM.
As to the way DTT is evolving here vs in Europe, it doesn't much matter
whether you think that starting with SD and adding HD after the fact is
better than what we did here. The simple fact is, both systems are
adding features that are USELESS to legacy receivers.
In Europe, that includes DVB-H, HDTV, AVC. Over here, that includes
A-VSB and possibly AVC. You are making a distinction where there is no
difference.
Bert
----------------------------------------------------------------------
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:
