[auspom]

Hi there - first time poster here so please be gentle!

I'm running a mythtv 0.26.1-fixes backend on ubuntu, and have 3 XBMC clients, one running on the backend, one running on a Mac and one on Windows. The mac and ubuntu backend are running frodo with the 1.6.9 cmyth addon, the windows box is running 12.3 alpha7 with 1.8.11 cmyth add on. Oh yes, I'm in australia and the EPG information source is the 8 day over-the-air jobbie. (I'm sure there's a more precise term for that!)

The problem I'm finding is that the XBMC EPG doesn't agree with either the Mythtv EPG or the OTA EPG when I use the TV directly. This can take the form of duplicate entries in the XBMC guide, entirely missing programs, overlapping programs and programs broken up into several pieces.

I had a dig around in the epg7.db file that (I think) serves as the basis for the XBMC EPG, and here is an example:



If there's any more information I can provide or logs etc any of the friendly devs would like me to provide please let me know.

Keep up the good work etc - hugely impressive so far.

[nickr]

What I can't ever work out is why XBMC runs a separate database for EPG when mythtv already has the same info in a database. It's f***ing weird.

Are those entries both from the same channel? Sometimes channels broadcast an SD version and an HD version?

If you are in Australia I understand the best epg data source is shepherd. You might want to look into that. http://svn.whuffy.com/wiki/

[auspom]

Hi nick, Yes they are both from the same channel - the idEpg field is the channel, in this case it was 7Two and there's only one version of that channel.

After playing around a bit more, I've found if I delete the EPG database using the option in settings, then the epg refills correctly, so maybe I might have to set up a cron job to delete it every day or so and hope XBMC works out it needs to refill it.

The data from the over the air EPG is fine - in fact better than any static source as it updates to reflect scheduling changes on the fly - I suspect it is this time/title changing that might serve to confuse cmyth, but not sure how to prove that. The fact that the myth epg on mythweb is correct suggests it is possible to handle this correctly.

If any of the devs want me to try to help with diagnosis then please let me know - I'm just not sure where to begin looking. I agree that having a local database for the epg is a strange duplication though, sure the devs could explain why it's necessary.

[cuccuizzo]

There is no need for a cron job, you can simply tell xbmc not to use the database for the epg.

Settings -> TV -> EPG -> Do not store the EPG in the database

Of course xbmc will download the entire EPG from Myth at startup and, depending on how many channels you have, it may take some time, so you also may want to limit the number of days to download.

I can't remember exactly which problem I had with the EPG, but I'm using this setting from a long time and everything works fine.

[nickr]

Why would it download the entire epg at startup? Surely it only needs to download what it needs at a time. It can't show a week of EPG in one screen, so surely it should only query what it wants to display?

Seems like there is some basic misunderstanding of client-server design missing here, unless there is some other explanation.

[auspom]

There is no need for a cron job, you can simply tell xbmc not to use the database for the epg.

Settings -> TV -> EPG -> Do not store the EPG in the database

Of course xbmc will download the entire EPG from Myth at startup and, depending on how many channels you have, it may take some time, so you also may want to limit the number of days to download.

I can't remember exactly which problem I had with the EPG, but I'm using this setting from a long time and everything works fine.

Thanks for this, I'd found that setting - it works so long as you restart XBMC regularly, however if (like me) you have XBMC running 24/7 on your HTPC box, the discrepancies crop up again, which requires the running of "reset the epg database" to fix it - to me, this implies the EPG is still being cached somewhere.

From a brief browse of the code, I *think* that the cmyth code is trying to create a UID for each program by indexing (among other things) the start time of each program - however a key feature of OTA EPGs is that when start times drift, the EPG updates, which makes cmyth think that as the start time is different, the UID and therefore the program is different. This means that it creates overlapping entries in the EPG.

Seeing as the underlying mythtv EPG is accurate, perhaps deleting the cached EPG (cos it clearly is cached somewhere) then reloading it from myth might be a solution?

[auspom]

FWIW, this appears to be fixed in 1.9.1.14