[mythtv-users] Intel i965 video buffers errors on frontend - live TV

[evade.]

On 21/07/17 20:17, Ian Campbell wrote:
> On Thu, 2017-07-20 at 03:39 +0000, Mark Perkins wrote:
>> I don't think MythTV is any different to a standard PVR in that regard.
>> In the ordinary course of events with modern MythTV (say 0.27 or above)
>> I don't believe some sort of 10 sec pause is required (assuming
>> sufficiently capable hardware, proper network config, file system config
>> etc).
> 
> I always had the (possibly ill-informed) impression that it was also
> quite dependent on the type of tuner you had and the quality of the
> driver for it. e.g. I wouldn't be surprised if a network based tuner
> took a little longer to talk to and to begin streaming the new channel
> than the onboard tuner on some dedicated h/w PVR. Likewise I'm sure
> that the quality of PCI and USB tuners and their respective drivers
> varies greatly wrt tuning times independently of any issue myth itself
> might have. Whereas the h/w and drivers are something that h/w PVR
> manufacturers may or may not have optimised (and I expect some are much
> better than others). Plus with a PVR they are only supporting one
> specific combination of hardware and an integrated driver+application
> stack (quirks and all) whereas a myth system can host a wide variety of
> different tuner hardware, all with different quirks.
> 
> So even if there was someone willing to try and contribute to a
> seamless live tv experience, it would very likely need to be a full
> stack effort (so drivers as well as myth) targeting a particular subset
> of tuners (of course some subset would be generic, but by no means
> all). For it to be seamless across a wide range of tuner stacks you'd
> need a wide range of people willing to contribute such things...
> 
> Annecdata: My parent's Humax (I think?) PVR seemed to me to be fairly
> clunky for channel surfing, worse than our merely slightly clunky
> MythTV live experience (which is rarely used for live tv though).
> 
> (rereading the quoted stuff above I'm not sure now I've picked the
> right place in the thread to make this comment, oh well)
> 
> Ian.

Thanks for the insights Ian.  I think you're right.

By supporting a wide variety of hardware it makes sense that there's 
less optimisations of a particular card, it's firmware and drivers.

I wish there was a recommended hardware list, because ideally I'd buy 
the same tuner a developer users!
There's not a lot of choice in tuners for some countries though...


This conversation started as I had naively hoped that by putting a new 
system together with a newer tuner that it could change channel faster.

For reference my old system has two PCI "Technisat SkyStar2" DVB cards 
while my new one has a "DVBSky T982" PCIe card. 
https://linuxtv.org/wiki/index.php/DVBSky_T982  It's using the OpenELEC 
firmware.

I spent some time researching DVB-T PCIe based cards and there wasn't a 
lot of choice.  As it is I had to buy the T982 directly from DVBSky in 
China via email and Paypal!

evade.