How accurate is accurate recording in the UK?

A L

Hi there.

I have used TVHeadend for many years, with great success, but I have never tried the accurate recording option.

I have messing around with it, a bit, and the results seem to be a bit mixed - i.e. some recordings have had the beginning cut off.

I need to do some more testing and I think that certain channels are better than others.

I have tried extending the wake up system option, from 30 seconds to 90 seconds, but that does not seem to have improved things.

I am using the London Freesat bouquet and have the following EPG modules ticked:

EIT - with a priority of 10

Sky OpenTV UK - with a priority of 9

Freesat - with a priority of 8

I would be grateful for any advice on what I might do to improve things or anyone else's experiences with accurate recording.

davep

I used it with UK freeview at one time.

With the BBC channels it was perfect - recordings started with the station ident and ended just before the start of the next programme. It was less reliable with the major independent channels and even less so with the minor ones.

It fell apart when I added Freesat tuners and multiple EPG sources. Tvheadend assumes that the event ID in the EIT is common across EPG sources, and for Freeview and Freesat that is not the case (except for BBC channels for some reason). I tried rewriting the code to match on title and start time instead of eventID but was never able to make it work reliably.

You may have more luck if you don't use the OpenTV EPG.

A L

Thanks Dave.

I have done some more testing and you are right - BBC is very accurate but the minor action film channels are pretty poor and Channel 4 does not seem to work correctly, either.

Unfortunately, I need OpenTV as the EPG seems to be a lot better than Freesat's. I only have the Freesat module ticked to use the Freesat bouquet.

I will revert to just using 2 minutes of padding, either side of my recordings, as before.

Thank you for your input.

Adrian Smith

I can pretty much echo the experiences of @Dave Pickles.

I am using accurate recording with a UK Freesat setup. I have EIT, Freesat and Freesat (EIT) grabbers enabled. My recording profile has an extra warm up time of 300s and zero pre/post recording padding (I found that anything else for padding gave some strange results). I record everything using accurate recording and it's pretty solid on the main five UK channels (Channel 4 is the worst but this is pretty much always down to the broadcaster messing up the start/stop signals rather than TVHeadend). I also have a Freesat branded PVR (Humax Foxsat) and the results in terms of start/end recording times are identical between TVHeadend and the branded box.

The lesser channels available on Freesat are very variable in terms of whether or not the broadcaster provides the required identifiers in the EPG (Series and Episode CRIDs) and start/stop signals (EIT p/f packets in the transport stream) and, even if they do, whether or not these are transmitted at the right time. I spent a while a few years ago verifying this both in the TVHeadend logs and by comparison with identical recordings set on my branded receiver.

I occasionally have the odd recording that TVHeadend misses and I sometimes get additional episodes recorded from another series of the same programme. I believe (although I have never proven) that this is because a TVHeadend Autorec does "other things" to identify what to record (like matching on title) as well as matching purely on the Series CRID and Episode CRID in the EPG data. In my opinion, if using accurate recordings, the recording schedule (i.e. what to record) should be based solely on Series/Episode CRID and nothing else should be considered. Never had the time to delve into this though and prove whether or not my theory is correct.

I can also confirm that everything goes very wrong if you also enable a Freeview tuner and EPG (effectively the same as @Dave Pickles but the other way round). I also spent some time looking at this and came to the same conclusion in terms of Event IDs in the Freesat/Freeview EPG data. I had grand plans at one point to try to fix this and spent many hours tracing and delving into the code but, unfortunately, life got in the way and I've never had a chance to look any deeper.

In summary, I'd say it works with about 95+% success for me (but I'm only recording from the main five UK channels).