Yes, they will "adhere" to MPEG-2 in the robust channel. But then, I know what that term means, and you don't Even if they use an MPEG-4 codec, they will still conform to MPEG-2 in the program service. John Willkie -----Original Message----- >From: Bob Miller <robmxa@xxxxxxxxx> >Sent: Nov 10, 2006 9:33 PM >To: opendtv@xxxxxxxxxxxxx >Subject: [opendtv] Re: Let the games begin > >Listen, lets get real. If any broadcaster was to seriously consider >using A-VSB what would they do with it? > >Lets say they use it to simulcast their regular programming in a >robust mode so it is receivable for almost everyone. Are they going to >adhere to MPEG2 in this 1.5 Mbps robust channel? > >I doubt it. I think we break company with compatibility right there. >Yes A-VSB is backward compatible in theory but not in practice. We can >have our cake and eat it now. We can preach compatibility while going >incompatible. > >If I were a broadcaster and resigned to live with 8-VSB and A-VSB I >would go full A-VSB with one SD MPEG2 program using minimal bits and >use the rest with MPEG4 all at 1/2. > >How does that come out? Up to one Mbps up front cost. 18.39/2 = 9.20 >Mbps or more of which you need 3 Mbps for the required SD MPEG2 and >you have 6.20 Mbps or more left for a robust MPEG4. > >You can do a robust 720P with that right? Good for the speed limit >maybe. Maybe you could really crimp that MPEG2 by going with a B&W >weather and traffic map updated once an hour. Then you might get 8 >Mbps or more for the MPEG4 side. > >Of course this would not be in the spirit of staying the course with >legacy receivers. How long after the death of OTA do these legacy >receivers still control the discussion? It would seem that we should >be doing our utmost to stop the injection of more of these legacy >receivers into the OTA bloodstream instead of offering a subsidy for >doing so. > >Bob Miller > >On 11/10/06, Bob Miller <robmxa@xxxxxxxxx> wrote: >> On 11/10/06, Manfredi, Albert E <albert.e.manfredi@xxxxxxxxxx> wrote: >> > John Shutt wrote: >> > >> > > Bob had 5th gen LG boxes, using the same LG block that is in the >> > > DirecTV boxes. Bob's problem was that those "5th generation" >> > > chips didn't work nearly as well as the prototype "Cold Fusion" >> > > 5th generation box that got both Mark Schubin and Sinclair so >> > > darned excited two years ago. >> > >> > I know he tried some no-name clones with the 5th gen LG chip, and that >> > those clones didn't do "as well as" the prototype. But that doesn't mean >> > they are crap, either. We have all surmised the reason to be that they >> > weren't using the better tuner designs. >> > >> > AND >> > >> > The 5th gen LG-based USB receivers for PCs have been reviewed by the >> > trade press on several occasions, and they all do very well. I keep >> > repeating, over and over, that reception of TV stations from 80 Km using >> > only a (single) indoor antenna, reliably, from these LG 5th gen-based >> > designs is nothing to sneeze at. >> > >> > AND >> > >> > The 5th gen LG do not measure as well as the Samsung Gemini in certain >> > very key areas. >> > >> > AND >> > >> > The training techniques used in 5th gen sets can also be improved upon, >> > at least as far as I know, even without changing anything in the bit >> > stream. >> > >> > Put all of this together and it is ridiculous to think that the only way >> > to get acceptable DTT here is to use only A-VSB. That's just the sort of >> > annoying rhetoric certain politicians seem to crave. I try to ignore it >> > and not respond to it. I try. >> > >> > A-VSB is instead comparable to either HM or to 16-QAM modes in COFDM. >> > >> > For example, tuning the spectral efficiency down gradually to increase >> > robustness, using the SRS mode of A-VSB, is very similar to increasing >> > FEC in COFDM, and even backing down to 16-QAM. Same gradual improvement >> > in robustness. >> > >> > Yes, A-VSB can be used. No, it is not mandatory. And if you are after >> > spectral efficiency, you want to minimize use of A-VSB. >> > >> > Bert >> > >> > Minimal use of both 8-VSB and A-VSB is recommended and most likely. >> >> Bob Miller >> > > >---------------------------------------------------------------------- >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.