What's better: ATSC or DVB?

[daWsOn_s]

I would like to make question, USA uses ATSC to transmit digital television and it has 38Mbit per frequenncy. Europe now is starting to use DVB that allows on terrestrial service about 24Mbit. So what's the best one. As i read (correct me if I'm wrong) DVB allows to transmit more channels in the same transponders by sharing the band, then ATSC doesn't, right?
So why USA can now have a lot of HDTV free channel over ATSC and Europe hasn't already tested (for example Italy) HDTV over DVB-T for example? Do you think this is a bandwitch problem?

[woah!]

most ATSC channels here max out at 19mbps which would point to them using 2 channels per transponder. but as more and more HD channels light up here i see the bitrates dropping. i believe some are using 3 channels per which shows about 10-12mbps caps.

this is my view of how i have seen the HD fad grow over the last 2 years... i dont know much at all about how they go about splitting the channels / bandwidth etc.. i just know they must do it..

[DrP]

ATSC has a 38Mbit mode, but AFAIK no one uses it because it requires stellar reception conditions. 19Mbit in a 6MHz channel is what is normally seen.

As far as how many channels per mux goes, that's entirely up to the regulators and the mux operators. ATSC and DVB don't define the number of programs carried per mux.

[CityK]

Originally Posted by daWsOn_s

Do you think this is a bandwitch problem?

No, I think its a planning problem in your government and industry. Either that or an overall lack of inertia.

BTW, I believe you guys had trials during the olympics.

As DrP pointed out, the ATSC high data rate mode (which would use 16-VSB modulation) is not used. For the terrestrial broadcast system, 8-VSB is used and it delivers a TS payload of just under 19.4Mbps.

Digital Cable systems, on the otherhand, will (in general) use either 64-QAM or 256-QAM, which have TS payloads of ~27Mbps and ~38Mbps respectively.

[CityK]

Originally Posted by woah!

but as more and more HD channels light up here i see the bitrates dropping. i believe some are using 3 channels per which shows about 10-12mbps caps.

this is my view of how i have seen the HD fad grow over the last 2 years... i dont know much at all about how they go about splitting the channels / bandwidth etc.. i just know they must do it..

Do distinguish between the constant TS bitrate (~19.4 Mbps) and that of the underlying program streams.

Also note that, when it comes to encoding, we're not dealing with a steady state condition --- while program streams a couple of years ago might have been ~17Mbps, those with newer (and hopefully improved) equipment might be able to get by with 12Mbps streams with the same quality level .... although, just compressing more (without regard to PQ) in order to squeeze in as many stations/channels/programs as possible should indeed be a legitimate consumer concern.

[daWsOn_s]

Originally Posted by CityK

No, I think its a planning problem in your government and industry. Either that or an overall lack of inertia.

BTW, I believe you guys had trials during the olympics.

Yes I thinks so. It just that I see that all US broadcasters have now multicasting in HDTV like The CW, ABC, (ex) WB, (ex) UPN, FOX etc. and they are all free, aren't they? But, are all this HDTV channels transmitted only by ATSC? No satellite or cable airing? I've never understand the tv USA method.

As regards olympics, they were in HDTV yes for the first time in Italy, but only on DVB-S and it was not free!
Actually the best thing we could have now on DVB-T is channel with 5mbps video letterbox (widescreen doesn't exist ) and audio track at 192kbps (it's not so good for mpeg layer-2)

[CityK]

Originally Posted by daWsOn_s

they are all free, aren't they?

Yes.

But, are all this HDTV channels transmitted only by ATSC? No satellite or cable airing?

No, there is lots of cable and sat HD too...those, of course, are not free, and generally encrypted, making it difficult to get the content on to a PC.

As regards olympics, they were in HDTV yes for the first time in Italy, but only on DVB-S and it was not free!

Ah, I see. (I had thought there were DVB-T trials too, guess I was mistaken).

[daWsOn_s]

Originally Posted by CityK

Yes.

No, there is lots of cable and sat HD too...those, of course, are not free, and generally encrypted, making it difficult to get the content on to a PC.

Ah, I see. (I had thought there were DVB-T trials too, guess I was mistaken).

Yes there were too, but it was only a test, and inaccessible to people

[JohnnyMalaria]

Three reasons I see:

1. EU broadcast standards are much stricter (stuff that gets broadcast on US networks would never make it due to poor technical quality)

2. EU champions and adopters tend to be public institutions like the BBC rather than commercial outfits such as NBC, CBS etc (i.e., in the US, $ is king)

3. People ask "why should I pay to see higher definition crap?"

[woah!]

Originally Posted by CityK

Do distinguish between the constant TS bitrate (~19.4 Mbps) and that of the underlying program streams.

Also note that, when it comes to encoding, we're not dealing with a steady state condition --- while program streams a couple of years ago might have been ~17Mbps, those with newer (and hopefully improved) equipment might be able to get by with 12Mbps streams with the same quality level .... although, just compressing more (without regard to PQ) in order to squeeze in as many stations/channels/programs as possible should indeed be a legitimate consumer concern.

well i can say when Shaw cable started out with only about 3 HD channels i was capping at about 15mbps average. now they have about 12 HD channels and i never see more that 12mbps average now and i do see some pretty bad blocking on some of the content aswell. but whats better 3 great bitrate channels or 12 average ones.

HD Discovery does seem like the best one out of all of them which suits me just fine