CBeebies HD - Not available in all areas YET!

pete taylorpete taylor Posts: 1,977
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I have just read on the BBC red button page 9991 about the Freeview retune on 3rd September and there is an asterisk next to CBeebies HD and the text at the bottom declares that its "not available in all areas yet".

I know its on COM 7 at the moment, but does the "yet" word indicate to anyone that they will eventually get it on the PSB mux now it has been proven that a MUX with the latest encoder can successfully carry more than 5 HD streams?
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  • eladkseeladkse Posts: 1,948
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    While the grammar is indeed peculiar, I think you might be reading too much into it.

    As you say, with the latest encoders, there is the potential for all BBC HD channels to exist on BBCB at some point. However, I personally don't see it changing anytime soon.
  • a516a516 Posts: 5,241
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    Earlier this year there was a temporary change to the mux BBC B configuration resulting in lots of null packets (unused space). Recently around 1 Mbps is unused. It is a long term goal to have the BBC HD services on COM7 move to the BBC's own HD mux. It could be sooner than some think (I.e. well before 700 MHz clearance).
  • [Deleted User][Deleted User] Posts: 115
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    I expect it will happen when it is no longer commercially necessary to utilise Com7 (as it fills with commercial stations), when the BBC's contract with Arqiva expires, and when the budget allows for the new encoders.
  • technologisttechnologist Posts: 13,334
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    The problem is that as BBC B is a regionalised mux .. At the moment bbc3 / CBBC is coded by 7 coders. While BBC 4/C beebies needs only one. .....
    And when BBC one regions occur 7 becomes 18 ......
  • DWA9ISDWA9IS Posts: 10,557
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    The problem is that as BBC B is a regionalised mux .. At the moment bbc3 / CBBC is coded by 7 coders. While BBC 4/C beebies needs only one. .....
    And when BBC one regions occur 7 becomes 18 ......

    Are you saying that BBC 4 HD /Cbeebies HD would need 7 then 18 feeds to encoders in different parts of the country? Could the encoring not be done at one facility and then the correct mux version just get sent where its needed?

    It is already done for BBC A mux though and the BBC would need it done eventually, so if the infrastructure is put in place sooner than later it would surely make sense?
  • technologisttechnologist Posts: 13,334
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    Because of statistical multiplexing there needs to be a one coder per channel per mux - all talking to each other optimise the bit rate allocation to each.

    But when do you replace the hardware?

    One answer is when you can buy something which gives considerable improvement at a point when the existing is getting a bit tired...
    Or at a point when the coding and mux contract has a tech refresh point or renegotiation.

    At the moment ( without resilience) there are about half a dozen sets of code and mux for BBC B ...
    So to take BBC one regional means Atos buying about 12 to 15 sets .... I.e tripling the current investment .. Which BBC FTV ltd may hope to get some money frm regional itv .... But not any more than ....
    ( and as ch5 did not take up the capacity , BBC FTV ltd had to pay for unused coders for a few years..... So you can see their uncertainty )

    But what will happen at dso2 will both BBC and d3&4 have regionalised coding ?
    Or will there be just one regionalised mux ? If so is this BBC FTV ltd?
    Or which (new?) mux operator will it be and who will provide the service?
    And HD only PSB when? And what about s4c /alba ....
    And what will project aurora throw up?
    And what will the coders be like in a few years time..... .?

    Not easy decisions ....
  • eladkseeladkse Posts: 1,948
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    Surprised it hasn't sprung up on this board sooner, but null packets seem to be appearing again on BBCB.

    The somewhat unreliable digitalbitrate.com captured this earlier in the week:
    http://en.digitalbitrate.com/dtv.php?liste=1&live=9&lang=en&mux=BBCB

    Meanwhile, a516 reported null packets on Friday via Twitter:
    https://twitter.com/a516digital/status/523023791782637568


    Appears to be setup similarly to COM7 now - looks like there could almost be enough space for two HD channels at peak. Let the speculation, er, continue...
  • DragonQDragonQ Posts: 4,807
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    a516 wrote: »
    Earlier this year there was a temporary change to the mux BBC B configuration resulting in lots of null packets (unused space). Recently around 1 Mbps is unused. It is a long term goal to have the BBC HD services on COM7 move to the BBC's own HD mux. It could be sooner than some think (I.e. well before 700 MHz clearance).
    A side-note but have you stopped listing the layouts of the Freeview muxes on your website? Can't find them anywhere and the old bookmarks I have go to error pages.
    eladkse wrote: »
    Surprised it hasn't sprung up on this board sooner, but null packets seem to be appearing again on BBCB.

    The somewhat unreliable digitalbitrate.com captured this earlier in the week:
    http://en.digitalbitrate.com/dtv.php?liste=1&live=9&lang=en&mux=BBCB

    Meanwhile, a516 reported null packets on Friday via Twitter:
    https://twitter.com/a516digital/status/523023791782637568


    Appears to be setup similarly to COM7 now - looks like there could almost be enough space for two HD channels at peak. Let the speculation, er, continue...
    6 HD channels on BBC B was inevitable once Arqiva set COM 7 up that way. We've come a long way since BBC HD at 17 Mbps AVC...

    Hopefully satellite won't go the same route.
  • mossy2103mossy2103 Posts: 84,307
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    It's not all about raw bitrate though, especially when you factor in improved hardware encoders and improved compression algorithms (not to mention stat muxing).

    Mind you, one channel (or even two channels) per mux would not be sustainable (affordable/justifiable) anyway
  • Marti SMarti S Posts: 5,771
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    mossy2103 wrote: »
    It's not all about raw bitrate though, especially when you factor in improved hardware encoders and improved compression algorithms (not to mention stat muxing).

    Mind you, one channel (or even two channels) per mux would not be sustainable (affordable/justifiable) anyway

    The encoder hasnt changed it's still H264/AVC, unless they change to H265/HVC then we wont see any better compression.

    The only improvements can be from the stat muxing, and to be honest I doubt they can squeeze any more out of that without effecting the PQ at times.
  • mossy2103mossy2103 Posts: 84,307
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    Marti S wrote: »
    The encoder hasnt changed it's still H264/AVC, unless they change to H265/HVC then we wont see any better compression.
    As I recall (and this is somewhat relevant to my generic point), the BBC changed encoders a couple of years back, allowing more channels to be hosted on the mux. granted, that was not a recent change, but it does highlight the fact that encoder technology should be considered as opposed to just raw nitrates.
    The only improvements can be from the stat muxing, and to be honest I doubt they can squeeze any more out of that without effecting the PQ at times.
    Again, my comment was a generic one relating to raw bitrates (especially the quoted "BBC HD at 17 Mbps AVC..."

    But your points are relevant to any current changes of course.
  • popeye13popeye13 Posts: 8,573
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    DragonQ wrote: »
    We've come a long way since BBC HD at 17 Mbps AVC...

    Hopefully satellite won't go the same route.

    BBC HD PQ on DSAT will drop to the same level of DTT always.
    BBC claim there is no platform neutrality but we all know its still around.
    So if they do cram another stream into this, its going too look rather crap and DSAT will too :/
  • Mickey_TMickey_T Posts: 4,962
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    popeye13 wrote: »
    BBC HD PQ on DSAT will drop to the same level of DTT always.
    BBC claim there is no platform neutrality but we all know its still around.
    So if they do cram another stream into this, its going too look rather crap and DSAT will too :/
    How does BBC4-HD currently compare on DSAT with DTT given that on DTT it shares a mux with five other HD channels and three SD ones?
  • DWA9ISDWA9IS Posts: 10,557
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    Mickey_T wrote: »
    How does BBC4-HD currently compare on DSAT with DTT given that on DTT it shares a mux with five other HD channels and three SD ones?

    Digitalbitrate results:

    Dsat 11024 H:
    http://en.digitalbitrate.com/dtv.php?liste=1&live=69&lang=en&mux=11024

    DTT COM7:
    http://en.digitalbitrate.com/dtv.php?liste=1&live=9&lang=en&mux=COM7
  • DragonQDragonQ Posts: 4,807
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    Marti S wrote: »
    The encoder hasnt changed it's still H264/AVC, unless they change to H265/HVC then we wont see any better compression.

    The only improvements can be from the stat muxing, and to be honest I doubt they can squeeze any more out of that without effecting the PQ at times.
    AVC is the encoder but there are various ways of implementing it. Every time a new encoder comes out, it takes a few years to reach maturity, where its maximum potential is realised. Thus, a modern AVC encoding at a given bit rate will look better than an AVC encoding from a few years ago with the same bit rate.

    However, there is only so far you can go.
    popeye13 wrote: »
    BBC HD PQ on DSAT will drop to the same level of DTT always.
    BBC claim there is no platform neutrality but we all know its still around.
    So if they do cram another stream into this, its going too look rather crap and DSAT will too :/
    Satellite quality won't drop though: the BBC seems to love null packets and the average video bit rate is already at ~5.5 Mbps, which matches BBC B, even though it could be nearly double that if they wanted.

    ~5.5 Mbps AVC for 1080i is roughly equivalent to ~2.2 Mbps MPEG for 576i, and that's actually below what you'd see used on most SD channels on satellite. It seems the level of artefacting on SDTV is considered acceptable so with HDTV we only get greater resolution and no compression improvements. :(

    I imagine the BBC will start using 6 channels per transponder when BBC One HD regionalisation is completed, or at the very least 5 channels (mirroring the BBC B mux).
    lotrjw wrote: »
    What the hell is going on with that COM 7 graph? There's no way these HD channels have had an average bit rate of like 1.5 Mbps over the past 40 hours (assuming it is hours?).
  • AngusMastAngusMast Posts: 5,153
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    DragonQ wrote: »
    What the hell is going on with that COM 7 graph? There's no way these HD channels have had an average bit rate of like 1.5 Mbps over the past 40 hours (assuming it is hours?).

    Dodgy reception.
  • DragonQDragonQ Posts: 4,807
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    AngusMast wrote: »
    Dodgy reception.

    Hmm. I've given up on COM 7 myself: sometimes it works perfectly, sometimes I get no signal at all, and other times I get discontinuities all over the place. Not worth the trouble for two channels I almost never watch (and I can record Channel 4 HD anyway).
  • epsilonepsilon Posts: 4,583
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    lotrjw wrote: »

    A word of warning here. That website is moving to new servers and many of the scanner sites are offline. The information is likely to be out-of-date and becoming less useful as time goes by. It's probably better to wait for them to move to their new server and bring all of the scans back online.

    The COM7 results don't look too convincing, possibly a problem with the receiver/scanner?
  • kasgkasg Posts: 4,711
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    epsilon wrote: »
    The COM7 results don't look too convincing, possibly a problem with the receiver/scanner?
    a516 originally reported this on his site but has since pulled it, so is presumably unconvinced.
  • epsilonepsilon Posts: 4,583
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    kasg wrote: »
    a516 originally reported this on his site but has since pulled it, so is presumably unconvinced.

    I did notice a tweet from a516 about a reconfiguration but believe that was for the BBC B mux.

    I queried the validity of the COM 7 scans as they were all over the place with wildly varying total bitrates. A multiplex should run at a fixed bitrate. Also all of the streams on the 40 Mb/s mux are shown on some samples as only using around 10 M/bs overall so, yes, unconvincing.
  • kasgkasg Posts: 4,711
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    epsilon wrote: »
    I did notice a tweet from a516 about a reconfiguration but believe that was for the BBC B mux.
    Indeed, that is the Mux I was talking about, but I see now that wasn't at all obvious from the quote. He also put it on his website for a while.
  • AngusMastAngusMast Posts: 5,153
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    Well, the multiplex scanner is operational again and BBCB is still running with a minimum of 9Mb/s of null packets.

    http://en.digitalbitrate.com/dtv.php?liste=1&live=9&lang=en&mux=BBCB
  • AngusMastAngusMast Posts: 5,153
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    http://en.digitalbitrate.com/dtv.php?liste=1&live=9&lang=en&mux=BBCB

    There's a new stream on BBCB (London)

    The video captured by en.digitalbitrate.com is a caption saying "Shop Small, Small Business Saturday, 6th December"

    It's SD with Audio Description and Subtitles attached, but no LCN or name.
  • eladkseeladkse Posts: 1,948
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    AngusMast wrote: »

    You can tell the site is still somewhat broken... the screencap for the channel is FilmFour!
  • AngusMastAngusMast Posts: 5,153
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    I'm going to speculate that we will also see an ITV SD channel appear on BBCB, along with BBC4/Cbeebies HD.

    This is so ITV and Channel 4 each maintain their 20% of bandwidth on the multiplex.

    The ITV portion is subject to agreement between ITVplc and STV and UTV, they may not agree, but ITV would go ahead in England and Wales anyway.
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