HD plans "jeopardise" Freeview

Original thread has been archived.


The Digital TV Group, whoever they might be, have said OFCOM's plans for HD on Freeview jeopardise the future of the platform.


Firstly, the limited HD channels available doesn't meet viewers expectations, and secondly, the assumptions on which the plans are based are unproven - notably the switch to DVB-T2 and MPEG4 and could result in a decline in quality of the standard definition service.


http://www.digitalspy.co.uk/digitaltv/a88432/ofcoms-hdtv-plans-jeopardise-freeview.html

Original thread: http://www.tvforum.co.uk/forum/viewtopic.php?t=26666


As I said at the time, my main problem is at the moment the plan basically sees them try to cram 3.5 muxes into 2 to free up one mux for HD. If they bought the SDN mux into the PSB equation it would be a much better solution, with 3.5 muxes going into 3, one HD and then 2.5 non PSB muxes going into 2 muxes.

Ideally though extra space from the DSO should be made available for the expansion of Freeview into HD.

That's not going to happen because successive short-sighted governments insist on selling off national assets.

By auctioning the spectrum released by DSO, knowing that the main broadcasters will be out-bid, means that Ofcom are comdeming HD on DTT to second rate service compared to DCab & DSat.

HD will become more popular as the cost of the equipment reduces. But there needs to be a level playing field across all platforms. Ofcom may well be damaging the rapid growth of Freeview which is the main route for many as DSO approaches their area.

DTG is the body that manages the UK digital TV standards - ensuring "Freeview" boxes and receivers, and soon "freesat" I believe, perform properly, that transmissions are also correct, and ensures broadcasters, platform owners etc. talk to each other.

They are an important industry organisation - and not some fly by night pressure group - so it is an interesting (and not overdue pronouncement) that will deflate some of the more pie-in-the-sky assumptions being made about Freeview post-HD.


TICK


TICK

However - if Freeview HD goes ahead as currently planned moving all SD content from 6 to 5 muxes and shifting from to 8k 64QAM from the mix of 2k 16QAM and 2k 64QAM will mean we go from :

Now : 4 x 2k 16QAM 18Mbs each and 2 x 2k 64QAM 24Mbs each
Total : 120Mbs for SD services

Future : 5 x 8k 64QAM 24Mbs each
Total : 120Mbs for SD services

This isn't a drop in total SD bandwith - but the way it seems that Ofcom want it implemented is going to hammer PSB picture quality. As not all of the 5 muxes are equal, meaning all the public service channels are likely to be squeezed into two muxes - carried by 1100 transmitters, with the other three muxes only carried by the 80 or so current transmitter sites.

There is also a lot of optimism about encoder improvements, the Beeb in England statmuxing BBC One (once the Raman and Coding and mux projects are completed), and DVB-T2 delivering lots of bandwith in a single mux for all UK OTA HD services. (If they adopt BBC R&Ds MIMO aerial system then they may get a LOT more bandwith - though this requires aerials with dual polarisation and low noise amps or two down-link cables)

There really should be at least two additional HD muxes - even if they are SFNs and on a single frequency nationwide...

I never really understood ofcoms HD plans as they really only accounted for the PSB's releasing a single HD channel. Great, but not great for the long term future when it will be expected that every channel will be HD.
Given that HD tellys are the only tellys you can buy nowadays, it seemed shortsighted at best.

Well Ofcom are being optimistic if they think that every PSB will get a 24/7 fitted into one HD mux...

BBC HD and SVT HD (which is carried on the Swedish equivalent of Freeview/TUTV) are both running at around 16-20Mbs H264 to deliver decent quality - and some of the Sky HD channels are running higher than this. They are delivering stunning pictures - which is what HD TV owners who are used to BluRay and HD-DVD are coming to expect.

If the PSB HD mux is switched to DVB-T without MIMO then it will deliver between 40-45Mbs. That is enough for two services at cracking quality, or three at pretty good quality. Ofcom are expecting HD encoders to improve massively in the next 5 years, as they expect to fit at least 4 (BBC, ITV, C4, Five) HD serrvices into a 40Mbs mux - which delivers around 10Mbs per service - that is the same data rate as SD DVD using MPEG2. HD is possible at that rate (HD MPEG2 in the US is sometimes hitting levels that low) - but it isn't stunning to look at as it is either softened or blocky.

Your views are flawed

LUXE TV HD at 10Mbs is fantastic.

Luxe TV HD is far from fantastic and has some of the least demanding HD material you could imagine. It is certainly - by a country mile - the poorest HD channel on the UK HD DSat platform (ignoring C4HD when it is showing SD upconverts). It is like watching one of the HD demo loops in the high street - slow moving, super saturated, noise free content with shots that last a week, and nothing that would come close to taxing the encoder.

If Luxe TV HD carried Football, Rugby, Wimbledon, Glastonbury or the Eurovision Song Contest at that rate I suspect you'd have a very different view.

what does that look like out of interest? I presume C4's pres upscaler is vastly superior to internal TV ones so it won't be as mushy as freeview on the HD TVs in a shop.

It looks VERY good indeed. Two reasons :

1. The upscaling is good - though as it is still broadcast as 1080/50i the display still has to de-interlace. It certainly looks better than SD upconverted in my display.

2. The broadcasts are in HD and the compression is in the HD domain. As a result any compression artefacts are HD resolution not SD, so subjectively they are far less obvious. Also - C4SD is (or was) resolution reduced to 544x576 on satellite, so upscaling a 702x576 source to 1080i rather than downscaling it to 544x576 is going to make the improvements even more obvious! C4 SD is also massively compressed (not as bad as ITV1 but getting there)

I certainly watch and record SD stuff on C4HD rather than C4SD if I remember. (Now if only you could remap Sky boxes so that 104 was C4HD!)

The DTG have now published their own proposals which would see 12 HD channels on Freeview by 2013, and in time up to 40 HD channels on the platform.

Digital Spy


I don't quite get how they plan to achieve it - I read it as basically keeping two of the "analogue" signals to create the new HD muxes.


Though I think they're right in taking a long-term view for HD on Freeview, unlike OFCOM, I'm not really convince this is viable either - seems a bit over ambitious. However in principle I agree more space is crucial to get HD on Freeview right - and if I had to choose one or the other, it would be the DTG proposal.

Yes - they are suggesting using two nationwide Single Frequency Network on two frequencies - not lots of frequencies arranged so as not to interfere. This means just two 8MHz slots would need to be retained for TV use.

They are proposing to use DVB-T2 not DVB-T - and if they use MIMO they may be able to achieve 44Mbs or much more on a single frequency. (I've read that 60Mbs per mux might be possible) MIMO uses both H&V polarisation and either requires two aerial cables or an active aerial (which transposes either the H or V in frequency so both H and V can be carried by a single cable)

If you can get 60Mbs then you could probably get 12 x 10Mbs HD services in two SFNs. BBC HD is currently 16.5Mbs though there is a hope H264 encoders will improve.

DTG objected to the ofcom plan partly on the grounds of it using DVB-t2, so these plans contradict their original assertions.

bbc/itv/4 & 5 control the vast majority of DTT bandwidth so they should use the existing space - as ofcom have suggested - for HD.

all reserch, including that done for DTG members shows that more people want more SD services and even local tv ahead of HD.

The old boys club at DTG should not be allowed to grab more spectrum - for free - just to maintain their members monopoly on viewers, while the HD viewers lobby help them by putting format over content and choice.

If broadcasters want to add a HD along the SD, +1 and genre varients of the (mostly) same content (more4/e4 for example) they should bid for the spectrum like everybody else.