[opendtv] Re: something

  • From: "John Willkie" <johnwillkie@xxxxxxxxxxxxx>
  • To: <opendtv@xxxxxxxxxxxxx>
  • Date: Sat, 29 Nov 2008 20:25:43 -0800

One wonders if the many, many, IP items needed to accommodate ATSC MDTV (MPH
is a brand name limited to a single vendor, and I'm not sure it will
survive, but perhaps Bert "knows" otherwise) and things like HE-AACv2, IP
stacks and 416x240 15.7:9 video using MPEG-4 AVC will be worth it,
particularly at the distances that Nick was mentioning.

Also, since one of the sections that you included from that press release,
Bert, mentioned "service protection" I'm not sure that the possibility of
having to pay for MDTV for marginal improvements at distance will be worth
that cost.

ATSC MDTV is intended to improve reception in mobile, pedestrian and
hand-held environments.  It's been tested muchly at ground level among
hi-rises and in cars on city streets and highways, but not so much in the
far field, where 8-VSB seems to work just fine.  

Nobody is going to be happy viewing non-HDTV content on an HDTV set,
especially where that involves a newer, more expensive HDTV set, and
possibly paying for some or all MDTV content.

I know this will never sink in with Bert, but I also strongly suspect that
he will never have a MDTV device in his hand or car.

It's also important to note that MDTV uses 8-VSB transmission.  It just does
some very interesting tricks with 8-VSB.  Also important to note: it will be
VERY-difficult-to-impossible to have HDTV coexist within the same transport
stream as MDTV.  The minimum bit hit for MDTV seems to be (per press
notices) 2 MB/sec.  

The NewsHour with Jim Lehrer won't prevent MDTV in the same transport
stream, but just about any dance, sports or other event with high motion
will be impaired significantly were MDTV in the same stream.

John Willkie

-----Mensaje original-----
De: opendtv-bounce@xxxxxxxxxxxxx [mailto:opendtv-bounce@xxxxxxxxxxxxx] En
nombre de Albert Manfredi
Enviado el: Saturday, November 29, 2008 3:41 PM
Para: opendtv@xxxxxxxxxxxxx
Asunto: [opendtv] Re: something


nicholas kocsis wrote:
 
> There was an occasion in the early fall when we had
> a warm spell during which the weakest Buffalo channels
> were lost for days on end (a Syracuse station 200 miles
> away came in wonderfully well for all of an evening).
> I blamed it on a propagation problem related to ducting
> when signal is captured by a boundary of hot and cold
> air layers in the atmosphere).
 
Speaking of mimicking the effects of analog, this is the perfect case for
incorporating the MPH standard into all 8-VSB sets. When these propagation
conditions occur, stations which transmit their most valuable subchannels in
a relatively robust MPH mode will still be receivable by consumers too
distant for regular 8T-VSB reception. Just like in analog times, on these
days the image quality won't be great, but at least the station is viewable.
And the closer-in receivers will go on with 8T-VSB, more or less as before.
 
Bert
 
_________________________________________________________________
Proud to be a PC? Show the world. Download the "I'm a PC" Messenger
themepack now.
hthttp://clk.atdmt.com/MRT/go/119642558/direct/01/ 
 
----------------------------------------------------------------------
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.


 
 
----------------------------------------------------------------------
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: