[mythtv-users] Recording length

[Michael T. Dean]

On 08/08/2007 03:09 PM, Brad DerManouelian wrote:
> On Aug 8, 2007, at 12:00 PM, Brian D. Frost wrote:
>> I have been using mythtv for a few years and have always wondered  
>> why a 60 minute show shows up at 59:23 (or something similiar) when  
>> I use the OSD? Basically, the OSD always shows that shows are  
>> slightly shorter than the recordings runtime...
>>
>> anyone else?
>>     
> I believe the explanation was that different portions of the  
> recordings are encoded differently (different bitrates for  
> commercials, for example) and the method MythTV uses to figure out  
> the length doesn't account for that perfectly.
>
> There are a few topics that come up in the archives I found by  
> searching for "recording length". This one seemed particularly  
> informative:
> http://www.gossamer-threads.com/lists/mythtv/users/187263

That's definitely true of some types of recordings (mainly those from
digital capture cards, like HDTV and firewire).  However, in this case,
since the time is so close to the "expected" time, I think it's actually
just the fact that starting to record/changing recordings isn't
instantaneous (and I'm betting the capture card is a PVR-x50 or a frame
grabber).

See http://www.gossamer-threads.com/lists/mythtv/dev/21068#21068 for a
nice explanation of some of issues (though that particular behavior may
have been changed since then).  Or, start at
http://www.gossamer-threads.com/lists/mythtv/dev/21063#21063 and read
the rest of the thread for a lot of info.

Mike