[vdr] Undetected channels on transponders switching from DVB-S to DVB-S2

[Henning Pingel]

 Am Sonntag, den 11.09.2011, 13:49 +0200 schrieb Udo Richter 
 <udo_richter at gmx.de>:
> There's currently no 'official' method to track down channels that
> are no longer announced. There's a trick however: Modify your
> channels.conf so that all channel names start with [outdated], then
> start VDR and wait for a full transponder scan to finish. All 
> existing
> channels will be renamed back to their proper names, and all 
> remaining
> [outdated] channels can be dropped after some grace period.

 That sounds like a handy trick. I will try to use this as a workaround.

> I use a more advanced variant using a small patch and a plugin, both
> currently not publicly released: The patch tracks a 'last seen'
> timestamp to all channels, where 0 means 'not seen since VDR start'. 
> A
> matching plugin holds a second channel list and periodically syncs
> with the regular channel list, with the additional info 'first seen'
> and 'last seen' tracked persistently across VDR sessions. Also, the
> plugin renames channels that are gone for some time so they can be
> identified and deleted.

 That sounds *very* interesting to me. If I can assist you in going 
 public with this patch + plugin, please let me know. I currently don't 
 see a reason to reset the timestamp to zero on VDR start, but I probably 
 just don't get your concept yet.

> This has however two downsides: First, a VDR that hasn't been running
> for some time will instantly mark all channels gone, and the same
> thing happens if a source is temporarily unavailable - for me, DVB-T
> is regularly not plugged, so all DVB-T channels are usually marked as
> gone.

 More examples: Multiswitch/DiSEqC/cable malfunction.

 It would potentially be possible to check a list of channels that are 
 considered to be outdated against a web service like Channelpedia (as 
 long as it offers many concurrent users to send in their own channel 
 list at the same time - and Channelpedia doesn't do that yet...).

 Thanks!

 Cheers,
 Henning