Some reasoning behind the limit of Freeview channel

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codyc1515

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Topic # 85178 15-Jun-2011 12:26

I was reading the article on Freeview on Wikipedia when I came across this statement:

"Freeview satellite broadcasts have declined in quality since the service launched as TV1 is now being broadcast many times to provide region specific adverts, this reduces the bandwidth available to other channels that transponder."

This seems like a reasonable explanation, but it sure is a waste of spectrum in doing so. Also, at almost any given time the three (or so) Chinese channels broadcasting on Freeview|HD have the same CCTV broadcast on, that is also a waste of spectrum (in my opinion), why not just have one CCTV channel? At least put something unique on!

/end rant

Nety

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Reply # 481686 16-Jun-2011 06:33

It was done by the TV stations because their prospective advertisers were demanding it. It was a sad day for us the end users.

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sbiddle

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Reply # 481692 16-Jun-2011 07:46

Spectrum isn't the same issue on DVB-T - there are 3 DVB-T MUX's but only 2 DVB-S. There is also planning (and spectrum available for future DVB-T expansion if required.

From memory the quality of channels other than TVNZ ones was largely unaffected on DVB-S due to the TV1 changes, most of the changes were TVNZ cutting the bitrates on their own channels to compensate. There are actually far better ways of handing regional advertising such as the UK model, but TVNZ opted for multiple channels.

dickytim

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Reply # 481698 16-Jun-2011 08:01

Nety: It was done by the TV stations because their prospective advertisers were demanding it. It was a sad day for us the end users.

Not completely, more advertising revenue provides better TV in the long run.

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Reply # 482134 17-Jun-2011 10:07

They should have done what they do in NORDIG countries like Sweden do (SVT1/SVT2 etc), where the they have several channels pointing to the same single high quality video bitstream, then just change the video PID at advert time to point to one of a few lower bitrate audio/video streams for local adverts. In Sweden they actually use it to insert local news rather than adverts, but the same scheme could have been used. They might use it for adverts too, but I'm not sure about that.

hdinsider

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Reply # 482480 18-Jun-2011 11:09

sub: They should have done what they do in NORDIG countries like Sweden do (SVT1/SVT2 etc), where the they have several channels pointing to the same single high quality video bitstream, then just change the video PID at advert time to point to one of a few lower bitrate audio/video streams for local adverts. In Sweden they actually use it to insert local news rather than adverts, but the same scheme could have been used. They might use it for adverts too, but I'm not sure about that.

I wonder how clean the switching is with this style. (Hope they change the audio PID too!!).

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cyril7

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Reply # 483084 20-Jun-2011 11:38

The above substream switching is done by the Beeb also, I mentioned this a couple of years back, seems to work pretty well for them.

Cyril

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Reply # 483476 21-Jun-2011 04:42

hdinsider:
sub: They should have done what they do in NORDIG countries like Sweden do (SVT1/SVT2 etc), where the they have several channels pointing to the same single high quality video bitstream, then just change the video PID at advert time to point to one of a few lower bitrate audio/video streams for local adverts. In Sweden they actually use it to insert local news rather than adverts, but the same scheme could have been used. They might use it for adverts too, but I'm not sure about that.

I wonder how clean the switching is with this style. (Hope they change the audio PID too!!).

Its perfect. You dont notice anything. It all happens in the middle of a second or so black.

Yes, does the audio too.

hdinsider

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Reply # 483666 21-Jun-2011 14:21

sub:
hdinsider:
sub: They should have done what they do in NORDIG countries like Sweden do (SVT1/SVT2 etc), where the they have several channels pointing to the same single high quality video bitstream, then just change the video PID at advert time to point to one of a few lower bitrate audio/video streams for local adverts. In Sweden they actually use it to insert local news rather than adverts, but the same scheme could have been used. They might use it for adverts too, but I'm not sure about that.

I wonder how clean the switching is with this style. (Hope they change the audio PID too!!).
Its perfect. You dont notice anything. It all happens in the middle of a second or so black.

Yes, does the audio too.

A second or two of black to air between program and commercials wouldn't be acceptable to the broadcasters here. I guess the other problem would be how low to drop the bitrates for those regional ads? You wouldn't want to go too far below 2MB/s (at MPEG2), so it's maybe not saving as much bandwidth as it's worth.

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codyc1515

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Reply # 483703 21-Jun-2011 15:25

Also, lets not forget about Free-to-air channels that are broadcasted on SKY encrypted.

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Reply # 483736 21-Jun-2011 16:33

hdinsider:

A second or two of black to air between program and commercials wouldn't be acceptable to the broadcasters here.

Its not two seconds of black. They ususally do it in the middle of quick black fade out and in and they switch from the previous show, through to the regional news. It happens very quickly. I've see it loads of times, and you dont even notice. Here in NZ often have transitions that look visually the same when we go from a show to adverts. Honestly, you wouldnt even know it happened - its not an uncomfortably long period of black or anything like that.

naggyman

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Reply # 484106 22-Jun-2011 06:41

That would work quite well here, so all of the programs don't pixielate up on our nice HD TV. Freeview Satellite looks horrible on a HD TV.

Morgan French-Stagg

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