# Tivo and Accurate Recording (AR)



## tdenson (Oct 3, 2002)

Anyone know if there's any plan to support Accurate Recording. My Topfield has very nice functionality in this area in that it uses the AR signal to position the start of the recording but it also uses pre-padding so if the broadcasters get it wrong (as they often do by a few seconds) you can rewind to the actual beginning.


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## Brangdon (Feb 9, 2001)

I don't know. I've missed the start of several programmes. I believe the old TiVo would change channels a few seconds early, because it knew it would take some time to transmit the infra-red pulses, and then an unknown time for the set-top box to switch. Now it's all integrated, I suspect the new TiVo does not start the channel change early, but it still takes time so it can be a few seconds late. Or rather, it is more likely to be late: it might actually be the network starting slightly early.

Padding sorts it out; I guess I'm saying I feel I need front-padding more often than I used to, for things like BBC News which tends to start precisely at 6 O'clock.


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## Tony Hoyle (Apr 1, 2002)

It seems to add some padding.. all the programmes I've recorded have been a couple of minutes early.. similar to the V+ I guess.


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## jonphil (Aug 7, 2002)

Generally recordings have been fine, but the problem is you can never plan for TV stations who decide to start before the scheduled time.


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## tdenson (Oct 3, 2002)

Brangdon said:


> I don't know. I've missed the start of several programmes. I believe the old TiVo would change channels a few seconds early, because it knew it would take some time to transmit the infra-red pulses, and then an unknown time for the set-top box to switch. Now it's all integrated, I suspect the new TiVo does not start the channel change early, but it still takes time so it can be a few seconds late. Or rather, it is more likely to be late: it might actually be the network starting slightly early.
> 
> Padding sorts it out; I guess I'm saying I feel I need front-padding more often than I used to, for things like BBC News which tends to start precisely at 6 O'clock.


I think you misunderstand. The old Tivo cannot have known anything about AR because it is a feature of Freeview. The information is transmitted by the broadcasters as they actually start the program (not the program guide time).


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## Major dude (Oct 28, 2002)

How is the Overlap protection function working out.
It is supposed to allow for overrunning shows and sacrifice the start of lower priority shows that clash as a result. Presumably it would work for early starts for high priority shows as well.
But how is it working out in practice so far?


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## tdenson (Oct 3, 2002)

jonphil said:


> Generally recordings have been fine, but the problem is you can never plan for TV stations who decide to start before the scheduled time.


Precisely, that is the whole point of AR.


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## cwaring (Feb 12, 2002)

jonphil said:


> Generally recordings have been fine, but the problem is you can never plan for TV stations who decide to start before the scheduled time.


Sky1 regularly start their shows a min or so early; as does Channel 5. Padding takes care of it though


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## tdenson (Oct 3, 2002)

Just thinking - It would actually be quite easy to (sort of) fake Accurate Recording by just always positioning the play position pointer at the scheduled start of the program when pre-padded. I'm surprised it doesn't actually do that by default, it seems so obvious. 
My wife won't use padding as she doesn't like to have to then find the beginning - this is a particular issue on radio programs where you can't see what you're doing (not helped by the bug which won't let you fast forward radio programs).


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## VirginMediaPhil (Nov 27, 2009)

The worst culprit is The One Show which always starts at exactly 18:58 to allegedly get ahead of Emmerdale on the other site, with the BBC saying it's to let the 2 minute news bulletin thing start before 8pm.

Although, I haven't actually watched The One Show since Adrian & Christine left (I watch Daybreak now instead of course). So, it's not much of an issue anymore but for some is quite annoying.


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## OzSat (Feb 15, 2001)

VirginMediaPhil said:


> The worst culprit is The One Show which always starts at exactly 18:58 to allegedly get ahead of Emmerdale on the other site, with the BBC saying it's to let the 2 minute news bulletin thing start before 8pm.
> 
> Although, I haven't actually watched The One Show since Adrian & Christine left (I watch Daybreak now instead of course). So, it's not much of an issue anymore but for some is quite annoying.


Sometimes it is nearly 3 minutes early at starting.


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## pteronaut (Dec 26, 2009)

What happened to PDC?


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## Mimizuku no Lew (Jan 3, 2011)

It would appear that PDC requires Teletext.

http://en.wikipedia.org/wiki/Programme_Delivery_Control


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## okonski_uk (Dec 28, 2000)

PDC wasn't available nationally - certain areas of the country either didn't have it, or only implemented a partial use of it for certain programmes. As it required the teletext stream to provide the updated times to the downstream recorders, viewers of non-terrestrial channels (which invariably had no teletext service) like Sky had nothing to work with.

Similarly, it required the recorder to scan channels is was not recording to check in there had been a change to the running time(s). The S1 TiVo (for example) could not make use of it, and since the bulk of VMs output on TV has no text (either old or new) there was no need to implement it for the new TiVo.

A good primer on the technology is here: http://625.uk.com/pdc/


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