[no Bug] TVServer fails to update Channel Name or LCN for existing channels during scan. (1 Viewer)

[SciDoctor]

If a channel exists in the database and a fresh scan for channels is done then changes to LCN or Channel name are not updated. Should this happen ?

Workaround. You need to delete the channel first and then a fresh scan will now find the new channel with correct name and LCN.

In the logs the channel 'Big Deal' has changed its name to 'Movie Mix' on the same LCN 32.
The first scan fails to find these details, the second scan after deleting 'Big Deal' does find the'new' channel.

I have peviousy seen this error when the UK HD channels changed their LCN some weeks ago, I manualy changed their LCN in the end.

You can test this by either manualy changing a chanels name or LCN (to something entirely different to any other channel) and do a scan and see what happens.

Tried both with/without enable 'channel movement detection'.

 

[SciDoctor]

Additional logs attached for failure of 'channel movement detection'



Dave ja vu moved from 482.2 to 506.0, a scan failed to update correctly with 'channel movement detection'

 

[jameson_uk]

There are a couple of issues here but they are not bugs but limitations of the TV server scanning.
First off you have tuning details and channels. So BBC One is a channel but you may have DVB-T and DVB-S both with different tuning details for this channel.

When you do a scan you are basically scanning tuning details and in the case of "Big Deal" to "Movie Mix" this would have seen the same tuning detail but there is no way to update the channel name. The tuning for "Big Deal" would have tuned fine to "Movie Mix" but it is not very helpful. When you delete the channel and do a scan it creates a new channel because there is not one already and hence it gets the right name. The reason the channel name from tuning details does not automatically update the channel name is those looking at the tuning code never figured out how to handle multiple tuning details.

eg. if you have Channel A on DVB-T and DVB-S and then on DVB-T it gets changed to be called Channel B what do you do? You could rename the channel but then potentially the DVB-S tuning detail would no longer point at the right channel.

The same goes for channel numbers (BBC is 1 on DVB-T but 101 on DVB-S) and if one changes do you update both? I think prior to 1.3 LCN was stored against each tuning detail so actually both 1 and 101 would have worked (and if only the LCN changed this would most likely have been picked up) but this caused other issues...

The other issues about movement detection is based on DVB specs. Unfortunately Sky, Freesat nor Freeview not actually use the defined method for moving channels. Sky and Freesat create a new tuning detail and briefly have two running at the same time. I seem to remember Freeview being more straight forward but with Dave-Ja Vu they should have the internal identifiers the same but I am guessing they just set it up as a brand new channel with different IDs (hence no way to track the move)

These are improvements that are needed to the scanning code but it is currently working as designed