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BBC West to opt from Grandstand

... to show Gloucester v Bristol (January 2005)

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SD
Steve D
Markymark posted:
deejay posted:


Now, tinkering with U-Links and switches may well have tricked the system so that this match could have been offered to the viewers in the accepted Sport format of 16:9 for digital and 4:3 centre-cut-out for analogue, but it will have disrupted transmission while it was set-up by both Plymouth and Bristol. Far safer to allow Bristol and Birmingham to opt out in the usual manner to carry the game, even if it did mean that Birmingham opted slightly too late, and Bristol passed a 14:9 image to West and South-West viewers.


Surely both the BBC 1 network digital sustaining feed, and any OS feeds come via the main station router, as would outputs to the TX/uplink ? If so transparent cuts can surely be dropped in and out using an X-Y router panel ?


I believe it's the analogue network on their router. They couldn't soft-opt from a 16:9 digital network feed because they work in 4:3. The reason why BBC ONE is fed to the English regions at a locked-off bit rate is because they opt the MPEG stream for DTT - not sure about those that have been updated to work in 16:9 though. Because the nations have pres areas and full stat-mux installations their BBC ONE feed is in the stat-mux bundle with all the others.
SD
Steve D
deejay posted:
When older regional centres opt-out of network, because the galleries are 4:3 they have been configured to chop the top and bottom of the picture off and pass a 14:9 image to the analogue and digital chains. They are appropriately ARCd so that analogue gets 14:9 letterbox and digital gets 14:9 pillar-boxed.


Yes, the digital output is 4:3 zoomed up to 14:9 pillarbox on a 16:9 raster, but they don't do any ARCing in the analogue chain to chop off the top and bottom of the picture. There is a nice little box which keys black bars top and bottom of the 4:3 frame on gallery output, thus faking a 14:9 letterbox effect to match the network output. Gallery monitoring and cameras tend to have the safe frame marked on them, but I saw a piece into Breakfast from the Brighton un-manned on Monday which was framed for 4:3 full-frame, so the top of the contributor's head was missing, and he looked very large!
MA
Markymark
Steve D posted:
Markymark posted:



Surely both the BBC 1 network digital sustaining feed, and any OS feeds come via the main station router, as would outputs to the TX/uplink ? If so transparent cuts can surely be dropped in and out using an X-Y router panel ?


I believe it's the analogue network on their router. They couldn't soft-opt from a 16:9 digital network feed because they work in 4:3. The reason why BBC ONE is fed to the English regions at a locked-off bit rate is because they opt the MPEG stream for DTT - not sure about those that have been updated to work in 16:9 though. Because the nations have pres areas and full stat-mux installations their BBC ONE feed is in the stat-mux bundle with all the others.


Yes, I understand that, and that the DTT/D-Sat opts are actually controlled by GPIs from the local analogue vision mixer's tally outputs. But I would have thought the network sustaining feed and outputs for DTT/D-Sat must pass thought some sort of router either in the SDI or ASI domain, or are they really only 'patchable' via U-Links ?
SD
Steve D
Markymark posted:
Steve D posted:
Markymark posted:



Surely both the BBC 1 network digital sustaining feed, and any OS feeds come via the main station router, as would outputs to the TX/uplink ? If so transparent cuts can surely be dropped in and out using an X-Y router panel ?


I believe it's the analogue network on their router. They couldn't soft-opt from a 16:9 digital network feed because they work in 4:3. The reason why BBC ONE is fed to the English regions at a locked-off bit rate is because they opt the MPEG stream for DTT - not sure about those that have been updated to work in 16:9 though. Because the nations have pres areas and full stat-mux installations their BBC ONE feed is in the stat-mux bundle with all the others.


Yes, I understand that, and that the DTT/D-Sat opts are actually controlled by GPIs from the local analogue vision mixer's tally outputs. But I would have thought the network sustaining feed and outputs for DTT/D-Sat must pass thought some sort of router either in the SDI or ASI domain, or are they really only 'patchable' via U-Links ?


Their sustaining feed is the 4:3 analogue network NOT the 16:9 digital feed. It's the analogue network which would pass through the router, and could be broken out at U-links or patched on the X-Y panel.

As far as my thought process tells me, the only way they could have done it was to have passed a 16:9FHA feed from Birmingham on to their analogue router (I assume distribution would have been in the analogue domain anyway) then switched out the box that keys in the 14:9 fake bars. They'd also have to switch the ARC in the DTT chain to pass-through, and ARC the feed to the analogue chain with a 4:3 CCO.

Obviously they wouldn't have been able to satisfactorily add any graphics, as the fake 14:9 Astons are in completely the wrong place - too far in to the centre of the screen and too far up - or down depending what graphic they were using, as well as being stretched to bu**ery of course!

All in all it's not too difficult to see why they took the decision they did!

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