[mythtv-users] MythTV records but doesn't write to disk...

[Roger Heflin]

Brian Wood wrote:
> On Monday 15 December 2008 08:16:24 Udo van den Heuvel wrote:
>> Udo van den Heuvel wrote:
>>> Udo van den Heuvel wrote:
>>>> Hello,
>>>>
>>>> Yes, another one of these.
>>> After yet another reboot things changed!!
>>> Hmmm...
>> I can remark though that MythTV happily mentions that it's recording
>> while there is NO data coing in due to soem issue.
>> I tested more:
>> So even if the card has no antenna (no signal!) MythTV won't complain
>> and just pretend to record.
> 
> It's not pretending. It is actually recording the static or whatever else 
> might be being captured.
> 
Not on digital is isn't, it not passing anything at all out of the 
card, the card is running, but if nothing is being passed out would 
agree with the original poster it is pretending to record.

> 
> What about if you are recording a "technical difficulties" slide?
> 
> Myth has no way to know about "content", though you might be able to detect a 
> non-changing video (color bars?)
> 
> If a station is off the air, it might well come back up in the middle of a 
> program, and you might want to record what's left of the program.
> 
> Making content judgements is probably beyond Myth, at least at this point.
> 
> You might also be able to detect a no-signal condition if you could get 
> reliable signal strength indications.
> 
> But on the whole, I don't think I'd want Myth to be making "content" 
> decisions.
> 
> 
> 

Brian,

On digital recording with no signal gets *NOTHING* it should be pretty 
easy to make a content decision on that.  Technical difficulties in 
this case is a totally useless empty file.

I have had it happen because of PCI bus issues caused the actual tuner 
card's internal cpu to segfault (internally) and lockup, I did finally 
find the message in messages about it, and a reboot was required to 
correct it once it happened (it happened several times)     After I 
worked around the PCI bus issue by not using disk on the built in PSO 
internal controller it quite starving the PCI card slots and it has 
not happened to me again.

But it would be a nice thing to have for the other more likely case of 
  an antenna issue, or something that would fall over to secondary 
channel in the event of issues on the first channel (the second part 
is alot harder to do, and likely is not that useful), but the first 
part of warning when a channel is weak is more likely to be more 
useful in a number of cases.

There should be a way to setup a timer and validate that a min data 
rate should be there otherwise a warning message is output, and the 
min could be set pretty low to not cause warnings when something was 
not actually wrong.