[mythtv] rolling up my sleeves: a few questions about commflagging

[Brian J. Murrell]

On Mon, 2014-01-27 at 13:01 +0000, John Pilkington wrote: 
> 
> Yes, it's fetching it from the DB, but AIUI that was changed quite 
> recently with the intention of solving the long-standing problem of 
> variable frame-rates.
> 
> http://www.gossamer-threads.com/lists/mythtv/users/557752#557752

Ahhh.  I see.  The time between keyframes is available which means that
a frame rate, at least from one keyframe to another is calculatable.  In
practice, at least from a couple of recordings I have looked at here,
keyframes are approx. every 15.  Perhaps that is plenty enough to get an
accurate enough calculation of commercial lengths with changing
framerates.

I will have to look into where mythutil --getmarkup is getting that data
from and see if it's available during commflagging, which is typically
happening live, during recording (to take advantage of page caching to
avoid re-reading the frames from disk).  Certainly it could be a
post-recording-complete process if necessary but that doubles the disk
I/O and adds latency to the commercial flagging data.

Thanks John!

b.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 473 bytes
Desc: This is a digitally signed message part
URL: <http://www.mythtv.org/pipermail/mythtv-dev/attachments/20140127/b3592208/attachment.sig>