HD Broadcasting

Interesting. So the mux is ‘built’ at BCM? In WA, the mux is built at each site.

no, the MUX is always built at the playout centre… that ASI stream is then transmitted to the transmitter by the Telstra long haul digital video network (while 7 stills uses satellite delivery as backup, 9 and 10 have redundant paths on the DVN)

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Thanks!

So why do you reckon Seven has gone for MPEG-2 primary HD in Qld?

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Does seem odd that this has suddenly happeend, at a time when BCM is in the process or midst of closing down?

Maybe THAT’S why ie. when it’s moved to the new JV playout, then it will go MPEG 4 HD and SD again as well.

This might only be temporary because of the need to have the cricket in HD?

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While I agree that this is likely only a temporary move, I’d personally like to see it be permanent.
It’s 2018, there should be no need for a 7SD feed.
Nearly all people have HD (even 4K) TVs now. Out of everyone I know, my parents actually have the oldest TV, which I believe they purchased in 2007… as I’ve said, even it is capable of showing the new 7HD channel.

As a side note, having only 7HD available has had the added side effect of now having an HD channel on the single digit LCN numbers (LCN 7), something that I know many people here have advocated for for ages.

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If it’s only temporary then whatever they do next is a step back IMO

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An MPEG4 HD channel can have better picture quality than an MPEG2 HD channel though, particularly at lower bitrates.

SBS is a good example. Their 1080i HD simulcast of the main channel looked alright in MPEG2. But when SBS VICELAND HD was launched and the main SBS HD channel switched to the MPEG4 format, the picture quality if anything, looked slightly better than it was at a higher bitrate MPEG2 HD channel before despite having a considerable reduction in the bandwidth allocated to make room for a 2nd stream.

Now on the flipside, MPEG2 HD at a good bitrate probably looks slightly better than MPEG4 HD. Hard to explain this, but it’s particularly evident with the edges of on-screen text and subtle things like that. But while there’s been improvements in video encoding technology, nothing less than about 10mbps for the video stream (particularly during fast moving content like sport) would really be acceptable MPEG2 HD viewing. With networks trying to squeeze everything they can out of their multiplexes to fit as many channels as possible in, unfortunately I wouldn’t expect to see double digit mbps for HD video streams anytime soon!

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Are you remembering it correctly? It was a blocky mess for months even years before they went MPEG-4. Easily the worst example of High Definition in the country. They needed to do something a lot quicker than they did.

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Of course they could move to MPEG4 but realistically that is never going to happen unless an MPEG2 simulcast is available

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For those (like myself) that have been wanting the HD channel to be on the single digit LCN.

Here’s the current set up in North QLD.

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Yeah…now I think about it, SBS HD in MPEG2 was quite blocky for a while. Although if I’m being honest, the picture quality of all MPEG2 HD multichannels (or at least the ones I saw via terrestrial TV here in Sydney) didn’t look that great between the rise of commercial datacasting services and networks finally deciding that MPEG4 HD main channels were the way to go. And despite being in 720p HD, ABC News 24 was only ever upconverted SD except for maybe some NYE Fireworks telecasts.

I think the bitrate of SBS HD was later increased (didn’t it sometimes go up to 10mbps or more?), but the splitting of the streams into two MPEG4 services somehow made for a considerable improvement in quality.

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Even though there’s debate about the quality of HD in MPEG-2 v. MPEG-4, I can say the MPEG2-HD we’re getting for 7HD now is FAR better than the previous 7SD service.

I’m surprised they haven’t added a HD add-on to the watermark. I honestly thought they’d be flogging the fact that 7 is only available in HD now to viewers, and the easiest way to do so would be with the HD watermark.

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The day has finally arrived @NQCQTV2. I’m jealous :stuck_out_tongue:

They could at least drop 71 though.

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Panasonics have a ‘swap’ function where you can for example swap LCN 50 for 5 etc. It makes it easy to have HD channels on single digits.

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What would be the occupied space by one MPEG-2 HD channel compared to one MPEG-2 SD plus one MPEG-4 HD?

About the same space as one HD MPEG2 channel

It would depend on a number of factors. How many services are there, how many are MPEG-4 already and how bandwidth hungry the content is. WIN are getting away with broadcasting WIN SD at 2.5 MBit tonight. Their HD channel is right now running between 6.5 and 7.8 MBit. GWN7 on the other hand have no MPEG-4 services at all, SD or HD, and they manage to have 7mate HD at a steady 8.3 Mbit and GWN7 SD at 4.6 MBit.

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And no 7flix!

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I’d love to have this functionality.
I was fiddling with the settings on my TV before. The closest I can come is to set a “favourites” list, which then allows you to use your own channel numbers, the only thing is it doesn’t let you skip a number, ever single number has to be occupied. So I can’t just have ABC HD on 2, and 9HD on 9, while everything else stays the same, I have to have something occupying 1,2,3,4,5,6,7,8,9,10,11,12, etc. which is annoying

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