[mythtvnz] On-air guide vs XMLTV

[Stephen Worthington]

On Fri, 16 May 2014 14:12:48 +1200, you wrote:

>Hi guys (again)
>
>Please don't blast me for a common question: I find nothing definitive 
>in the archives.
>
>I believe I have tv_grab_nz-py working.
>
>I will say what I did, incase it is helpful for someone else (or stupid, 
>so you can correct me). I found zero docco about this on the web:
>
>Ran it in from ~ with the configure option
>It created a .xmltv directory with selected channels in tv_grab_nz-py.conf
>mv this directory to /home/mythtv
>symlink this dir back to ~/.xmltv
>symlink /home/mythtv/.xmltv/tv_grab_nz-py.conf to 
>/home/mythtv/.mythtv/Freeview.xml
>symlink ~/.mythtv to /home/mythtv/.mythtv
>
>Maybe there is a command line option to specify the output, but I 
>couldn't be arsed finding it, so probably would stuff it up in the 
>future too... I think this will help me later.
>
>OK, now I noticed something interesting:
>In the EPG I seemed to be getting extra information for channels marked 
>"useonairguide" in mythweb. This information showed up as programme 
>categories in parenthesis after the title in the guide. If I uncheck 
>"useonairguide" and look at the programme info (press "I" on the 
>frontend) I can't see it anywhere. I am (vaguely) aware that the guide 
>data allows for much more detail than is provided OTA, so I wondered if 
>this was simply being put in its rightful place by xmltv-proc-nz (Thanks 
>hads for all the work you've put in on these scripts!)
>
>Some information is still present, and the EPG changes programme colour 
>as appropriate, but I'm sure it was better before.
>
>As I lamely attempt to describe what I'm seeing I seem to be talking in 
>circles. It's like the useonairguide flag functions the opposite way to 
>what I'm expecting.
>
>This is a bad email. I will try to explain better if I have not been clear.

The "useonairguide" option means to use the tuners to collect EIT
data.  It should never be mixed with using downloaded data via
tv_grab_nz-py, as they clash with each other.  That is likely what is
happening for you.  Each channel should be set up to use only one
source of EPG.  The DVB-S channels have good EIT data - it is possible
to use that alone as a source for your EPG, just using the
useonairguide option and enabling tuners to be used for EIT
collection.  I have never done that, but I have used epgsnoop to get
EPG data from the DVB-S EIT streams once a day and that worked quite
well.  I still do that for my Sky EPG data.

If you do start using DVB-T, you will find that those channels only
have now/next EIT data (the currently playing programme and the next
one), which is useless.  The full EPG on DVB-T comes via the MHEG5
stream on each channel.  We were not originally able to get the MHEG5
data, until mhegepgsnoop was written (a big thank you to David
Moore!).  Now, the data from MHEG5 is the best source of EPG, and is
the source used (where possible) by tv_grab_nz-py.  The downloaded EPG
has also had additional processing done to it, for example to do some
fixups for some of the silly things done by the people providing the
EPG data, like remove "All New " from the front of some programme's
names.  So the downloaded EPG is the best option, unless you are
trying to run MythTV from somewhere without Internet access.

So I would recommend turning off all your useonairguide settings.  If
you are OK doing SQL, this would do it in one command:

  update channel set useonairguide=0 where useonairguide!=0;