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3D Fta Olympics On Channel 9 Tip Off


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#1 pheggie

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Posted 12 April 2012 - 10:48 PM

Received this tip off from Linkedin Stereoscopic 3d group in Australia
but we'll have to wait and see before official verification from ACMA

London 2012 Olympic Games 3D Broadcasts in Australia

I just had a chat with a contact in ACMA regarding the 3D broadcasts of the London Olympic Games in late July - August 2012.

International media report that the 3D coverage will include the opening and closing ceremonies using at least 12 to 14 3D cameras and 12 to 14 of the 26 Olympic sports, 10 hours a day.

Ch 9, the Australian free-to-air rights holder, has sought regulatory approval for a 3D broadcast trial which the ACMA board is considering at the moment.

There should be an announcement within the next few weeks.

#2 MLXXX

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Posted 12 April 2012 - 11:34 PM

That 9 was seeking ACMA approval for a television frequency to use for 3D Olympics coverage was announced in the media on or about 26 March 2012.

It was discussed a little in the thread Ch9's London's Olympic Coverage Announced, beginning at post #17:

http://www.mediaspy....ympic-coverage/


So pheggie, you're saying we may have to wait a few more weeks for an ACMA decision.

#3 GoForMoe

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Posted 12 April 2012 - 11:36 PM

It'd make most sense to deliver this using the 31 multiplex, plus a sizeable contribution from Nine towards operating costs for the community stations. I'm sure other posters have mentioned previously that the equipment transmitting the previous trials has been removed now. An article on this subject mentioned an afternoon 3D highlights package on the channel rather than a live broadcast in 3D

I'd suggest this is just Nine and the other commercial stations wanting to push 3D as another spectrum grab before a decision is made on the use for the 6th channel, using the new technologies argument they used with HD to prevent an open auction to new competition.

Still, I hope it gets up, watching the 3D coverage in 2D will be better quality than what GEM at 9Mbps will dish up.

#4 pheggie

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Posted 13 April 2012 - 02:49 AM

That 9 was seeking ACMA approval for a television frequency to use for 3D Olympics coverage was announced in the media on or about 26 March 2012.

It was discussed a little in the thread Ch9's London's Olympic Coverage Announced, beginning at post #17:


So pheggie, you're saying we may have to wait a few more weeks for an ACMA decision.


I didn't know about that report thanks for the link
But it appears confirmation of ACMA's decision might be a few weeks away according to the insider at Linkedin

#5 alanh

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Posted 13 April 2012 - 02:56 AM

The first thing to ask is who is going to pay for the extra advertising to cover costs. There has been a lack of interest in continuing trials after the last ones. The last time the ACMA offered and there was no takers.

The link suggests channel 41
It cannot be used in Sydney because of analog TV in Bouddi will be interfered with.
It cannot be used in Melbourne because of interference to and from ABC Ballarat which is receivable in Melbourne. It cannot be used in Brisbane because of Noosa/Tewantin
It cannot be used in Adelaide either because of interference to the SBS Spencer Gulf high powered transmitter.
This covers most of the audience because WIN & NBN did not participate in the last trial.

MLXXX suggests channel 31
It is clear in all mainland state capitals but for Melbourne due to interference to Prime in Central Victoria and Adelaide where C31 analog is still on air. The problem with this channel is that the old analog transmitters used by community TV. With the exception of Perth are all either medium or low powered and not equipped to transmit digital. It is upto SBS as to whether the will rent their standby transmitter and retune it to channel 31 except Melbourne.

So the Nine network really only has one option. For the open and closing ceremonies to use reduce the data allocation of channel 9SD to the smallest practical allocation. Use the rest of the data available from GEM, Go! and 9Extra for an MPEG-4 signal using frame compatible S3-D They may also have to switchoff the MPEG1- level 2 audio as well. This will leave the AC3 audio. This will leave the 2-D HD viewers out in the cold and the SD viewers with a medocre image which may break up on movement. Maybe even they should suggest viewers us the analog signal!

As for the long term the ACMA is investigating the use of DVB-T2 and MPEG-4 at the moment. If this happens all broadcasters will be able to include S3-D into their multiplexes.

AlanH

Edited by alanh, 13 April 2012 - 03:08 AM.


#6 CWulf

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Posted 13 April 2012 - 09:46 AM

Hi Alan

The reference to 41 will be to the probable LCN - not an RF channel.

While NBN did not get involved in the last lot of 3D trials WIN certainly did. Both as operator of the channel nine services in Perth and Adelaide but also with a seperate transmission from Knights Hill into the Wollongong area.

The reference to ch 31 seems pretty obviously to sharing the CTV digital multiplexes, not RF channel 31. Apart from the logistic issues around this, while it could technically be possible in Perth where the CTV digital is operating with 64QAM and would have sufficient bitrate, the use of QPSK in the other capital cities only allows sufficient bitrate for the current SD program stream. Extra capacity would need extra transmission power to maintain coverage.

I would think it very unlikely that the Nine network will bastardise their current transmissions to provide the 3d trial content. This may be a suggested option should addition spectrum fall through but i suspect it would be coming from the network corporate spokesman rather than having any real technical basis.

I think the most likely outcome will be, as for the last lot of trials, parallel UHF transmissions on whatever channel is available in each market.

#7 alanh

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Posted 13 April 2012 - 03:30 PM

CWulf
Reports from previous trials & ACMA policy
http://www.acma.gov....RD/pc=PC_312131
RF channel 35 is still available in the same areas as it was last time
RF channel 29 was used last time in Adelaide is not available because it is used by high powered digital transmitters in the Riverland and in the South East.
RF channel 50 is still available in Brisbane

The LCN used last time was 40.
http://www.acma.gov....echnologies.pdf (Lists power of each transmitter)
The use of channel 'A' and channel 'B' have been dropped due to the digital restack removing channels 52 - 69. Yes there is one spare channel nationally after the restack.

As for transmitters, in the last trials the SBS back up transmitters were used, however they also were party to the trials transmitting the World Soccer Cup from South Africa.

I would be interested to find out what criteria the Nine Network is trying to test. I would suggest a DVB-T2/MPEG-4 trial on most of the same RF channels used last time. This will find out how many 3-D TVs can receive programs on this standard.

Use of Nine's own channel as mentioned above will cover more potential viewers for 3-D with a higher data rate. The loosers will be the 2-D HD viewers.

Alanh

#8 GoForMoe

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Posted 13 April 2012 - 04:08 PM

At least theoretically,

The channel would most likely appear as channel 41 and would broadcast games highlights from 11:00am to 4:00pm daily.

would allow Nine to maintain the GEM simulcast in 2D MPEG-2 HD for live coverage while running repeats in 3D.

That said, it would certainly be at a significantly lower bit rate than the 14Mbps used for the previous 3D Trial on its own multiplex. At current usage Nine would need to turn off Go, Gem and Extra to be able to deliver 14Mbps - which would result in huge receiver confusion and loss of revenue.

#9 CWulf

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Posted 13 April 2012 - 04:12 PM

Hello

Alan, you seem to be replying to my post, as you address your last post to me. You seem, though, to have gone off on some tangent which, while not necessarily incorrect or irrelevant to this topic, doesn't seem to have much direct relevance to my post.

I would have thought it would be appropriate if you were replying to my post to at least acknowledge that the content of my post had clarified some of the comments in your previous post (or corrected me if you thought I was wrong). That is:
  • the reference to 41 in the link in MLXXX's post was probably to an LCN (whether 40 or 41) rather than RF channel;
  • WIN was involved in the last 3D trials; and
  • the reference to "31 multiplex" in GoForMoe's post could possibly be to the CTV digital transmissions not necessarily the RF channel 31: although now the channel 31 CTV analog transmissions have ceased in all but Adelaide RF channel 31 could probably be used.
I don't really care what the previous test channels were or your conjecture on what channels or equipment may be used. We'll know soon enough I'm sure.

The other new element you've added is the suggestion that the trials could use DVB-T2! I've no idea who many receivers out there would be ready for DVB-T2 but I'd be very surprised if it was very many. It would seem to be a pretty big investment by the nine network to transmit something that very few viewers would be likely to receive.

#10 MLXXX

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Posted 13 April 2012 - 04:59 PM

The other new element you've added is the suggestion that the trials could use DVB-T2! I've no idea who many receivers out there would be ready for DVB-T2 but I'd be very surprised if it was very many. It would seem to be a pretty big investment by the nine network to transmit something that very few viewers would be likely to receive.

I almost fell off my chair reading that suggestion of alanh's! I can imagine how popular such an approach would be for viewers who purchased 3D TV sets in 2010 that only have DVB-T capacity (virtually all of the sets, I think).

As for my own suggestions in the past in other thread(s), I have not gone back to read them but I recall indicating that in Brisbane the community broadcaster although still licensed to use an analogue service on a particular radio frequency is not using it, and relies instead entirely on its digital allocation (which it broadcasts with a modulation robustness that allows use of relatively little power). If it were feasible to use the analogue frequency temporarily for 3D digital that might be easier than sharing the digital RF allocation, changing the modulation parameters, and boosting the power.

What Radio Frequencies might or might be used is technical speculation. Where there is a will there is a way. I don't think it will prove difficult to find a suitable Radio Frequency and suitable transmitter capacity in most if not all of the intended markets, if the ACMA has no objection in principle. Although it is possible to express opinions about availability and practicality of use of particular Radio Frequencies (as alanh has done in some detail) it is I think of greater interest at this point in time whether the ACMA can find an objection to the proposal on non-technical grounds, e.g. on public policy or commercial interest grounds.

Enhanced television coverage of Olympic sport would receive nonpartisan political support. It would be popular with members of the general public with 3D capable displays. The ACMA would be ill-advised to deny the Nine network's request, unless there are cogent reasons to do so. I suspect it might not even be necessary to classify the exercise as a technical test. To my mind, It would simply be in the public interest for the Minister to authorise use of otherwise unused Radio Frequency capacity, for this very special occasion of the 2012 London Olympics.

Edited by MLXXX, 17 April 2012 - 12:30 AM.


#11 alanh

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Posted 13 April 2012 - 06:32 PM

MLXXX,
The problem with the specifications by receiver manufacturers are not accurate. For example none of the TV manufacturers tell you even for the 3-D TVs tell you that they decompress MPEG-4 and in the last trial this was required in all 3-D TVs to get a pictures.

If the UK model is imported with a change of the power plug and a modification to the control firmware for our channels, these sets will all receive DVB-T2/MPEG-4 signals.

http://www.dvb.org/a...dwide/index.xml also shows which other countries are using DVB-T2 and which use MPEG-4.

Lastly you cannot use an analog TV transmitter to transmit error free high data rate digital. Where are the transmitters coming from? All state capitals will be moving all transmitters to band 3 within 2 years so it's not financially viable to buy a transmitters for a couple of programs.

As for using community TV to share their data stream, they would have to change to 64QAM to increase the data rate on low powered transmitters is not worthwhile.

The ACMA is investigating the rollout of MPEG-4 and DVB-T2 regardless of S3-D.

A reason why ACMA may not approve another trial is that there is no worldwide standard for the terrestrial transmission of S3-D, there is only a production standard. They don't want people to buy 3-D sets on the presumption that they are futureproof. See the link above. The methods currently being used cannot display full HD pictures in S3-D.

You have not read my email very well because I have indicated which cities will have problems with channel allocation. Remember as I have already stated that in all but Sydney, backup SBS transmitters were used in State Capitals. In Sydney the old datacasting transmitter was available.

AlanH

#12 GoForMoe

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Posted 13 April 2012 - 06:49 PM

To my mind, It would simply be in the public interest for the Minister to authorise use of otherwise unused Radio Frequency capacity, for this very special occasion of the 2012 London Olympics.

The main public interest issue is whether the public might be misled from another trial broadcast into thinking that 3D transmissions were to become permanent in the future. There's been a few threads on here and complaints I've seen on news articles on the subject from people who have bought 3DTVs under a misapprehension of the nature of the 'trial' as a trial. Sales people certainly are willing to ignore minor details like 'just a short trial' in favour of selling a 3D TV.

Oddly I agree with AlanH to the extent that a trial of DVB-T2 would be a good justification for a new technical trial - as would trialling an MVC signal as opposed to the side by side used in previous trials. MVC on DVB-T would also allow testing of general MPEG-4 capability.

Of course the other option is doing anaglyph 3D on Go! or GEM - which would take advantage of the 3D source but not do anything to advance technology. It would open it to a much wider audience though. Ten recently did this with an episode of Talkin' Bout Your Generation.

Another option could be a trial of using UHF27 - which is a point of consideration in the current planning for the post-restack environment. It's nominally available in all cities, though obviously caution over interference with analogue SBS28 transmissions would be needed.

Edited by GoForMoe, 13 April 2012 - 06:56 PM.


#13 MLXXX

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Posted 13 April 2012 - 07:08 PM

You have not read my email [sic] very well because I have indicated which cities will have problems with channel allocation. Remember as I have already stated that in all but Sydney, backup SBS transmitters were used in State Capitals. In Sydney the old datacasting transmitter was available.


Alanh, I presume that if the Nine network is seeking temporary licensing to use special RF allocations around the country it does not usually use, then it can be expected the Nine network has in its corporate hands a preliminary assessment that it would be feasible to do so.

We will hear soon enough whether the ACMA approves the matter in principle, and if does approve the matter in principle, then in due course we will learn of the particular arrangements arrived at for various locations in Australia.

The main public interest issue is whether the public might be misled from another trial broadcast into thinking that 3D transmissions were to become permanent in the future. There's been a few threads on here and complaints I've seen on news articles on the subject from people who have bought 3DTVs under a misapprehension of the nature of the 'trial' as a trial. Sales people certainly are willing to ignore minor details like 'just a short trial' in favour of selling a 3D TV.


I think the ACMA should seriously consider the permanent allocation of a single Radio Frequency in various parts of Australia to support ad hoc 3D broadcasting by any network, on a shared basis.

Oddly I agree with AlanH to the extent that a trial of DVB-T2 would be a good justification for a new technical trial - as would trialling an MVC signal as opposed to the side by side used in previous trials. MVC on DVB-T would also allow testing of general MPEG-4 capability.


To the best of my knowledge, no television set in Australia can decode MVC. It is implemented in 3D Blu-ray players, and in 3D Blu-ray pc software. It is actually very specialised. There is no international standard for it for use in television broasdcasting.

To the best of my knowledge, very few TV sets in Australia can demodulate DVB-T2. I note though, as alanh has pointed out, that the manufacturers do not always disclose what their products are capable of. [A factor to consider here is licensing arrangements for use of advanced technology. If a TV set is to be used in a non-DVB-T2 region, it is conceivable any T2 functionality may be intentionally disabled to save the manufacturer licensing fees. I am speculating a little here.]

Of course the other option is doing anaglyph 3D on Go! or GEM - which would take advantage of the 3D source but not do anything to advance technology. It would open it to a much wider audience though. Ten recently did this with an episode of Talkin' Bout Your Generation.


Anaglyph would be interesting and novel for some viewers but ultimately frustrating. Even I as a great lover of 3D, find anaglyph trying of my patience. I get a similar feeling to that produced by crosstalk/ghosting. I don't think it would go down well with members of the public who have recently seen full colour 3D at the cinema.

#14 GoForMoe

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Posted 13 April 2012 - 07:20 PM

To the best of my knowledge, no television set in Australia can decode MVC. It is implemented in 3D Blu-ray players, and in 3D Blu-ray pc software. It is actually very specialised. There is no international standard for it for use in television broasdcasting.

What does a 3D blu-ray player do with an MVC video when it sends it to the TV?

I think the ACMA should seriously consider the permanent allocation of a single Radio Frequency in various parts of Australia to support ad hoc 3D broadcasting by any network, on a shared basis.

I agree, provided it is UHF27 - I'm still holding out hope for an open auction of the remaining spectrum on the 6th channel after community broadcasters take their share. We need more competition on commercial free to air TV. I don't think 3D or any technical trial should occur in the main TV band on any permanent basis.

FTA Satellite and IPTV on the NBN are probably the ideal places for 3D FTA content.

#15 MLXXX

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Posted 13 April 2012 - 07:47 PM

What does a 3D blu-ray player do with an MVC video when it sends it to the TV?

The player reads the core MPEG4 AVC, and the supplementary view MPEG4 AVC, and decodes them to produce Left and Right. It assembles Left and Right into a double height frame (a "frame-packed" frame), and sends that via HDMI using video packets. The 3D TV extracts the Left and Right from the HDMI video packets. Here is a link: http://www.best-3dtv...ame-packing-3d/

Edit: I see the webpage is a little out of date as it refers to the sequential display method used in first generation Full HD 3D displays. Since 2011, LED TVs for use with passive glasses have been available. These TVs update the screen simultaneously* for the Left and Right content, sending Left subframe information to odd-numbered lines and Right subframe information to even-numbered lines.**

___________

* LG updated their firmware with a more complicated sequencing, but it is still the case that the whole screen is updated with Left and Right information, rather than alternating the whole screen between Left content and Right content as is done for use with active glasses.
** Or vice versa.

Edited by MLXXX, 13 April 2012 - 09:58 PM.


#16 nbound

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Posted 13 April 2012 - 08:01 PM

I agree, provided it is UHF27 - I'm still holding out hope for an open auction of the remaining spectrum on the 6th channel after community broadcasters take their share. We need more competition on commercial free to air TV. I don't think 3D or any technical trial should occur in the main TV band on any permanent basis.

It cant just be UHF27 - it would have to be a different at each transmitter, else you will have issues with interference. Also it is beleived that many sets are incapable of tuning UHF27, mostly because of it being only 6Mhz wide.


I agree that we should make use of the unallocated channel in each area after the restack, preferably by opening it up for use by another broadcaster or broadcasters. Even the idea of it being a shared channel for the existing broadcasters special events is marginally more palatable then leaving it there doing nothing.

I actually hope in metro areas, the community stations end up carried by ABC or SBS, freeing up that last station everywhere. Though it could get a bit tight if NITV also suceeds in being carried by SBS.

FTA Satellite for 3D TV would be great, but most people dont realise dishes are for more than just Austar/Foxtel (and VAST/Aurora at a stretch for some people), I cant see it catching on (Though it would be great if it does).

#17 GoForMoe

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Posted 13 April 2012 - 08:18 PM

It cant just be UHF27 - it would have to be a different at each transmitter, else you will have issues with interference. Also it is beleived that many sets are incapable of tuning UHF27, mostly because of it being only 6Mhz wide.

For the purposes of a trial I think it's sufficient - Wollongong and Newcastle are the only non-metro areas that got the 3D trial in the past, and even then were on severely restricted power, with the Newcastle one being done from an inner city translator. Because I doubt there's a long term future for 3D, especially 3D via regional stations, I think the ongoing use of UHF27 as a place for technical trials by the broadcasters is feasible.

The previous trial ran FTA on Satellite - I believe to allow some regional cinemas to take a 3D feed of the football.

@MLXXX - interesting, so I suppose it's extremely unlikely we'll ever get MVC broadcast when it just ends up being top/bottom or side by side anyway.

Edited by GoForMoe, 13 April 2012 - 08:20 PM.


#18 MLXXX

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Posted 13 April 2012 - 08:36 PM

@MLXXX - interesting, so I suppose it's extremely unlikely we'll ever get MVC broadcast when it just ends up being top/bottom or side by side anyway.

It's a superior top/bottom as it can use the full number of horizontal lines, e.g. all 1080 horizontal lines. It's not like half-width side-by-side, or half-height top and bottom.

It's efficient, because the core view [Left] is referenced by the dependant view [Right]. There is often a lot of redundancy between Left and Right content.

I understand that one approach being considered for TV is to send the dependant view as a separate video stream in the multiplex. This would allow older MPEG-4 AVC capable sets to use the main view for 2D [Left].

#19 nbound

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Posted 13 April 2012 - 09:39 PM

For the purposes of a trial I think it's sufficient - Wollongong and Newcastle are the only non-metro areas that got the 3D trial in the past, and even then were on severely restricted power, with the Newcastle one being done from an inner city translator. Because I doubt there's a long term future for 3D, especially 3D via regional stations, I think the ongoing use of UHF27 as a place for technical trials by the broadcasters is feasible.

You would run into all kinds of issues with W'gong, Newcastle, and Sydney all broadcasting on UHF27. Even with reduced power. And the fact that many sets cant tune it makes it pretty pointless anyway.

The previous trial ran FTA on Satellite - I believe to allow some regional cinemas to take a 3D feed of the football.

Yes, for a trial thats great, but its hardly a long term solution for 3DTV. You going to pay $10-$20 to goto the cinema and watch an advert laden sporting event every week? Hell no, you'd get pay tv and use their 3D channels from the comfort of your own home.

#20 alanh

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Posted 14 April 2012 - 01:24 AM

All,
The digital restack which is to occur early in 2014 will allocate all transmissions to a group of transmitters on each site;
Group AH RF channels 6 - 8, 10 - 12 In mainland state capitals this means 6 = 7 network, 7= SBS, 8 = 9 nine network, 11 = ten network, 12 = ABC. All horizontally polarised
Group AV RF channels 6 - 8, 10 - 12 all vertically polarised
Group BH RF channels 28 - 33 inclusive all horizontally polarised
Group BV RF channels 28 - 33 inclusive all vertically polarised
Group CH RF channels 34 - 39 inclusive all horizontally polarised
Group CV RF channels 34 - 39 inclusive all vertically polarised
Group DH RF channels 40 - 45 inclusive all horizontally polarised
Group DV RF channels 40 - 45 inclusive all vertically polarised
Group EH RF channel 46 - 51 inclusive all horizontally polarised
Group EV RF channel 46 - 51 inclusive all vertically polarised

This will mean that locations which have a vertically polarised VHF and a Horizontal polarised UHF will disappear For example Goulburn Valley Vic, Canberra, Manning River, Wide Bay and Gladstone.
Making all transmitters on a single site in a narrow band of frequency will remove the need for any VHF/UHF antenna reducing antenna prices.

Note where possible new transmitters are being allocated to the above plan.

Yes there are 6 channels in each group, 2 government owned and 3 commercial. There will be no more channels available because channels 52 - 69 is soon to be auctioned to the phone/wifi industry. Channels 0, 1, 2, 3, 4, 5, 5A are not suitable for digital and channels 9 & 9A will be used for DAB+ radio.

To introduce S3-D on a permanent basis DVB-T2 is needed because it increases the data rate from 23 to 40 Mbit/s. MPEG-4 can halve the data required over MPEG-2. Only MPEG-4 has been used for any S3-D whether its transmitted or recorded. Since there is one vacant channel available nationally for ever more, then it should be reserved for a new national broadcaster or some other application. It should not be wasted by only using it in a few locations.

A DVB-T2 receiver can be fitted inside an HDMI plug.

HDMI can carry both frame compatible and non-frame compatible signals in full HD provided you use high speed HDMI.
Movie Blu-ray discs are recorded in MVC-MPEG-4 which uses a picture and a depth signal.

If all broadcasters convert toDVB-T2/MPEG-4 every broadcaster can transmit full HD stereoscopic 3-D at 50 frame/s progressive and SD program. At other times a pair of full HD 2-D programs and some SD programs simultaneously.

This means that terrestrial TV will be transmit 240 Mbit/s nationally compared with the NBN's 100 Mbit/s.

Alanh

Edited by alanh, 14 April 2012 - 01:37 AM.


#21 MLXXX

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Posted 14 April 2012 - 02:55 AM

Movie Blu-ray discs are recorded in MVC-MPEG-4 which uses a picture and a depth signal.

That statement could be read as a reference to 2D plus simple depth, a methodology of very limited use currently, and certainly not used for the picture content of Full HD 3D Blu-ray discs of motion pictures.

A Full HD 3D Blu-ray is encoded as picture 1 plus picture 2. It is just that picture 2 usually requires fewer bits to encode than picture 1 because it can reference image content in picture 1. Theoretically picture 1 and picture 2 could have zero correlation! They could still be encoded as MPEG4 MVC. It's just that the bitrate required would be higher than normal. Sorry to labour this, but alanh persists in describing Blu-ray 3D as being picture plus depth. At the risk of repeating myself excessively, here are some details [again]:-

The usual way of describing MPEG4 MVC as used for Blu-ray Full HD 3D movies is to refer to a main view (typically used for the Left camera view ) and a dependant view (typically used for the Right camera view). Both views are decoded in the Blu-ray player to arrive at a Left subframe and a Right subframe. These subframes are combined by a process called frame-packing and sent via HDMI to the display where the Left and Right subframes are extracted. They are then displayed in an alternating sequence if the display is for viewing with active shutter glasses, or simultaneously if the display is for viewing with passive polarised glasses (or uses a parallax barrier).

There is talk of incorporating depth maps in a future 3D video standard to facilitate consumer control of the strength of the 3D effect. (This would also facilitate compression to 2D + simple depth, for display by low bitrate, low resolution devices, such as mobile phones.)

However, currently there is no depth map encoded in Full HD 3D Blu-ray videos of motion pictures. All that is encoded is a main view and a dependant view.

The trend in 3D movie making at the moment is for improved accuracy and realism in the stereoscopic effect. This requires the Left and Right views to contain unique content, particularly for close-ups. A future development of creating a depth map, and including it in the encoding would help in real-time warping calculations in the player or the display for changing the stereoscopic volume, i.e. the effective interaxial distance (and any adjustment required for the point of convergence of the Left and Right views).

There is yet another approach: 2D + depth map + supplementary content. This method of "2D plus complex depth" could hold promise for the future.



#22 GoForMoe

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Posted 14 April 2012 - 02:56 PM

You would run into all kinds of issues with W'gong, Newcastle, and Sydney all broadcasting on UHF27. Even with reduced power. And the fact that many sets cant tune it makes it pretty pointless anyway.

I agree- which is exactly why I think it should use UHF27. 3D by the FTA networks should be taken for what it is - another spectrum grab to shut out competition. They have no interest in providing a decent 3D service and I'd suggest the broad consensus is that 3D is just a fad, one that the networks have openly admitted is to expensive to produce any significant amount of content for.

If the interest is genuinely in a technical trial, we can use the slightly off band, slightly harder to scan UHF27. If their goal is not a technical trial, it should be denied and taken for what it is, another attempt by the incumbent broadcasters to block competition. The only reason we don't have a UK Freeview style multiplex system carrying channels from different companies on the same frequencies was because the networks used HD as a spectrum grab to get 7MHz to themselves. They want to do the same with 3D and the final chance we have to break the 3 channel system.

If you want networks to keep treating viewers like crap, roll over and let them get away with the lie that is long term FTA 3D.

#23 alanh

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Posted 14 April 2012 - 03:31 PM

The ACMA does not regard channel 27 as a TV channel because it is only 6 MHz wide. There has been no clearance of two way radios. In addition the broadcasters want clearance to ensure that two way radios will not create complete signal breakup. They have this worry about channel 51.

In addition high powered TV transmission on channel 27 and 51 can cause communications on the adjacent bands to be unusable.

AlanH

#24 nbound

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Posted 14 April 2012 - 03:58 PM

If the interest is genuinely in a technical trial, we can use the slightly off band, slightly harder to scan UHF27.

ACMA would be unlikely to approve as most tvs wouldnt tune it, theres no point trialing something that will never work with the majority of tvs. The only reason that ACMA hasnt jettisoned UHF27 for other uses is likely that it makes a good guard band.

The original 3D trials were to test whether the 3D TVs being released at the time could reliably decode/display the information. (amongst other technical things, on the broadcast end, and of course a little marketing aswell ;) ). Its a bit hard to use that same excuses again. If it is approved its more likely to be on some "special event" basis, but im unaware of any precedent or any provision to allow that, and therefore i see it unlikely.

#25 alanh

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Posted 15 April 2012 - 12:31 AM

nbound,
If you look at the ACMA link in one of my posts in this strand the ACMA was very firm that this was a trial and that it does not indicate that this standard will be used permanently. So far nothing has changed from this. Also I remember that they had to chase Nine inparticular to supply their results from the trial. SBS supplied them as well.

The ACMA charges licence fees for the spectrum real estate used by all radio transmitters. It is unlikely to give any channel for free unless its a trial. As I stated before, who is going to pay for this broadcast. If it's the broadcaster, who is the advertiser?

Alanh