So it's even worse than we thought, and viewers are losing out on interactive services just so the BBC can broadcast a few hours of simulcast HD content a few months ahead of the rest. Considering the set top boxes won't really be ready for the market until later next year, they'd have been better off leaving things as they were and delaying the launch of HD on Freeview until broadcasters and manufacturers were ready.
So it's even worse than we thought, and viewers are losing out on interactive services just so the BBC can broadcast a few hours of simulcast HD content a few months ahead of the rest. Considering the set top boxes won't really be ready for the market until later next year, they'd have been better off leaving things as they were and delaying the launch of HD on Freeview until broadcasters and manufacturers were ready.
Yes I do sense some 'face saving' going on. I can understand the need the have 'real' broadcasts to allow R&D depts to refine designs, but surely better to set up low power
additional
DVB-T2 transmissions serving areas where those manufacturers are.
I wonder how many digital receiver manufacturers are based in Winter Hill's service area ?
I would argue the opposite. Why should the BBC be forced to delay HD roll-out just because ITV and C4 are dragging their heels? ITV HD is a non-channel at the moment, with a pitiful amount of HD content (the odd film, The Bill, the odd drama and some football), though C4HD is better (with quite a lot of their new commissions in HD, and most of their US imports and movies), but both will be SD/HD simulcasts (and thus carry SD content upconverted) BBC HD is a permanent HD channel so launching with BBC HD at least guarantees a single permanent HD feed...
You have to set a date to launch HD broadcasts and schedule the transmitter upgrade work, the encoder and distribution roll-out etc. Whether other broadcasters and receiver manufacturers are ready or not, you can't just change your mind and reschedule this stuff on a whim.
It makes sense to roll out the HD mux to new DSO regions as the DSO roll-out happens, avoiding two separate consumer re-tunes in a region.
Just because ITV and C4 are dragging their heels doesn't mean that the core infrastructure roll-out should be rescheduled - indeed doing so could delay DSO in other regions. (There is a finite, and quite small, pool of transmitter engineers who are actually doing this change-over work after all...)
It is very similar to the launch of 405, 625, colour and digital terrestrial - you start the broadcasts before the receivers are available.
Yes - the loss of the interactive streams to all to make way for the launch of HD is not ideal, but something has to give.
At least this means that the few receivers that are sold or put on display will have something to show...
As for R&D operations requiring low-power broadcasts - these have been available for months from Guildford and Crystal Palace transmitters - and so that is a non-issue. (If you're an R&D operation not in those patches you just need to rent an office in the coverage area for a short while to test your stuff, and it will all have to be properly tested by Freeview's licensing operation anyway)
So it's even worse than we thought, and viewers are losing out on interactive services just so the BBC can broadcast a few hours of simulcast HD content a few months ahead of the rest. Considering the set top boxes won't really be ready for the market until later next year, they'd have been better off leaving things as they were and delaying the launch of HD on Freeview until broadcasters and manufacturers were ready.
Increasingly BBC HD is NOT simulcast HD content - which is actually a problem for many.
Because there is now so much BBC content shot in HD - it isn't unusual for BBC One, BBC Two and BBC Four to all have HD shows overlapping (BBC Three has less HD currently), which means that usually BBC One wins for simulcasting and the BBC Two or Four stuff is scheduled separately on the two channels.
The current HD schedule is pretty repeat-heavy though - but over the next 12 months or so there will be a LOT of BBC HD content I would imagine. (Sport alone will include Winter Olympics, World Cup, possibly Commonwealth Games as well as the usual stuff)
I imagine that the BBC particularly want BBC HD on Freeview HD to be up and running for the Winter Olympics?
I was under the impression that one day all channels like BBC One, Two, Three, Four, ITV1/2, Channel 4, Five etc. would be in HD just like the switchover to colour TV. However, this now appears to be a practical impossibility since there's only room for four HD channels on Freeview. How many normal channels need to be scrapped to create enough space for one HD channel?
I was under the impression that one day all channels like BBC One, Two, Three, Four, ITV1/2, Channel 4, Five etc. would be in HD just like the switchover to colour TV. However, this now appears to be a practical impossibility since there's only room for four HD channels on Freeview. How many normal channels need to be scrapped to create enough space for one HD channel?
Well, it depends on which coding standards you use. Taking the UK's implementation as an example, Mux B if it ran at 64QAM/DVB-T1 (which post DSO it would have done) then about 6-8 SD services could have been squeezed it, the payload is 24 Mb/s. That mux is now being converted to DVB-T2, that will increase the payload to 35 Mb/s. BBC HD is running on D-Sat at 9 Mb/s, so using that bit rate you could almost get four HD services in that mux. However, 9 Mb/s is the bare minimum (with state of the art encoding) for HD. Sky are broadcasting their HD channels at a much higher rate than that, 14-20 Mb/s. I don't have Sky HD, only Freesat, so I can't comment on how much better Sky's channels look than the Beeb.
The problem is that analogue colour transmissions were simply an add on signal to the existing b/w one, so colour transmissions didn't require extra frequencies, or even bandwidth, and b/w receivers simply ignore (almost) the colour signal. HD on DVB is different. One thing countries yet to launch DVB services might consider, is to transmit all channels as HD, even if that means upconverting from SD. That way all receivers could be HD capable, but with dual SD and HD outputs. Viewers without HD TV sets, simply use the SD output of the box. That would make the boxes more expensive, but would avoid the need to duplicate the transmission of channels in both SD and HD.
Last edited by Markymark on 30 November 2009 4:21pm
So it is possible that one day all of the channels will just be HD and there won't be any dedicated channels like BBC HD or ITV HD anymore? I'm finding this hard to imagine at the moment, to be honest, but hopefully everything will fall into place within the next 10 years and everything will be HD.
It's the transition which is the problem. Over time Freeview probably could offer all the main channels in HD, but for space to be available SD channels need to close, and they're not going to close the SD versions of the big digital channels until those capable of receiving HD is at an acceptable level to justify it - and we're about 80-90% from that at the moment.
I was under the impression that one day all channels like BBC One, Two, Three, Four, ITV1/2, Channel 4, Five etc. would be in HD just like the switchover to colour TV. However, this now appears to be a practical impossibility since there's only room for four HD channels on Freeview. How many normal channels need to be scrapped to create enough space for one HD channel?
Well, it depends on which coding standards you use. Taking the UK's implementation as an example, Mux B if it ran at 64QAM/DVB-T1 (which post DSO it would have done) then about 6-8 SD services could have been squeezed it, the payload is 24 Mb/s. That mux is now being converted to DVB-T2, that will increase the payload to 35 Mb/s.
T2 is now up to around 40.25Mbs reliably in an 8MHz mux. (All the demo IBC muxes appeared to be at 40.25Mbs this year, last year they were at 36Mbs!) Not sure if we'll be running at that high a rate or if it will be dropped to nearer 36Mbs.
However another interesting issue is that the UK has been testing new DVB-T modulation parameters for 8k (one mux in the Border region I believe) which should be compatible with existing 8k-friendly receivers - and that could get 27-28Mbs out of a standard DVB-T mux as well. If that works we'll get another 15-20Mbs of capacity across the remaining 5 SD muxes.
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BBC HD is running on D-Sat at 9 Mb/s, so using that bit rate you could almost get four HD services in that mux. However, 9 Mb/s is the bare minimum (with state of the art encoding) for HD.
I think that the plan is to get 4 x 10Mbs services into the T2 mux eventually (though that doesn't leave much for main audio, audio description, subtitles and press red data) - assuming it runs at 40.25Mbs.
I think the initial planning was based on 36Mbs being T2's capacity (but 40 now appears feasible) and 12Mbs being the minimum for decent H264 1080i (but now the Beeb are running at 9Mbs at pretty good quality - if you ignore the bitrate obsessives and actually watch the pictures - BBC HD has got better with interlaced content since the new encoders were installed - but there are some issues now with lower quality sources being exposed...)
Most people agree that encoders will continue to improve - and with current encoders 9Mbs is pretty good. Dropping down to 6 or 7Mbs would deliver acceptable 720/50p I suspect - in the US the H264 satellite providers are running at 8Mbs and below. (Though quality isn't high for HD in the US - their MPEG2 ATSC terrestrial system is in a pretty terrible state)
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Sky are broadcasting their HD channels at a much higher rate than that, 14-20 Mb/s. I don't have Sky HD, only Freesat, so I can't comment on how much better Sky's channels look than the Beeb.
Sky are statmuxing though - and their movie channels routinely drop below 8Mbs - and seldom peak above 14 (their sports channels are given more bandwith). Some of their sport (Eurosport for example) peaks quite highly - but that is the benefit of statmuxing.
I wonder if Freeview HD will allow for statmuxing or if the spectrum is licensed on an absolute percentage, rather than relative percentage over time, basis?
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The problem is that analogue colour transmissions were simply an add on signal to the existing b/w one, so colour transmissions didn't require extra frequencies, or even bandwidth, and b/w receivers simply ignore (almost) the colour signal. HD on DVB is different. One thing countries yet to launch DVB services might consider, is to transmit all channels as HD, even if that means upconverting from SD. That way all receivers could be HD capable, but with dual SD and HD outputs. Viewers without HD TV sets, simply use the SD output of the box. That would make the boxes more expensive, but would avoid the need to duplicate the transmission of channels in both SD and HD.
That's what happened in the US in 1998 - sort of.
It will be interesting to see what Serbia does - they're launching DTT with DVB-T2. There is also now a NorDig receiver standard (for Norway, Sweden, Denmark and I think Finland) that includes DVB-T2 - Sweden is looking at a VHF SFN for HD content (at the moment SVT HD is only available in a few areas on DTT using DVB-T H264 - and nowhere near nationally). Finland is looking at a mix of DVB-T and DVB-T2.
There are still VERY good reasons for introducing DVB-T for SD (though H264 makes sense) as the receivers are very cheap - however in a few years time it will be pointless not introducing DVB-T2 if you are starting from scratch.
I believe the eventual plan for the UK will be to wait until T2 receivers are the norm, and then re-configure the UK muxes (possibly starting with the COMs) to T2 - either to provide more SD (H264 and T2 allow a LOT more channels than T and MPEG2) or to upgrade to HD.
So it is possible that one day all of the channels will just be HD and there won't be any dedicated channels like BBC HD or ITV HD anymore? I'm finding this hard to imagine at the moment, to be honest, but hopefully everything will fall into place within the next 10 years and everything will be HD.
I agree with your second paragraph.
Well ITV HD has already gone - it is now ITV1 HD, and Channel Four HD is also a simulcast of C4.
Of the terrestrials, only BBC HD is a 'best of' rather than a simulcast. I would expect that BBC One and BBC Two will eventually get HD simulcasts on some platforms (Freeview will be the last I suspect - but in 10 or so years I expect we will switch to T2 and H264 on more and more muxes as old kit dies and is replaced with Freeview HD compatible stuff), though I would expect BBC Three and Four to take longer (as they have lower audiences)
This is assuming the current BBC One, Two, Three, Four mix remains as now.
BBC News is an interesting one. They will be moving to BH in 3 years or so, and that will have to be an HD, or at least HD capable, set-up - to build it SD only would be absolute madness. This would allow news bulletins on BBC One to be HD, though wouldn't mean that the BBC News channel had to be.
In terms of programme production - this is moving to HD very quickly.
The BBC have 3 HD studios (TC1, 4 and and temporarily convert other studios (2 and 3 for instance) as required, and are likely to upgrade at least one more studio permanently in 2010 - they can't keep up with the demand for HD.
TLS are upgrading both Studio 1 and Studio 2 to HD soon, and I believe Fountain are well on the way. Sky have a significant number of HD studios and are building a new, all HD (in fact 3Gbps 1080/50p probably) studio set-up.
I don't think many OB operations are building SD trucks, and I doubt anyone will be building SD studios (apart from for regional news operations) these days.
It is actually getting quite difficult to buy broadcast quality SD equipment - I think Sony only have one SD studio camera in their range (the BVP-E30? I don't count the DXCs...) but they now have three or four HD ranges.
Similarly - whilst you can still get DVCam and DVCPro location camcorders, the minute you want to get above these basic formats, you're in DVCProHD, XDCam / XDCam EX, HDCam etc. territory.
If you want to make your shows to sell outside the UK to the larger, more lucrative markets (US, Aus etc.) then you need them to be HD even if the UK broadcaster you make them for is SD.
How many normal channels need to be scrapped to create enough space for one HD channel?
and temporarily convert other studios (2 and 3 for instance) as required, and are likely to upgrade at least one more studio permanently in 2010 - they can't keep up with the demand for HD.