[mythtv-users] Wrong Channel when recording?

[Mike Perkins]

On 13/05/15 23:25, John Pilkington wrote:
> On 13/05/15 22:51, Hika van den Hoven wrote:
>> Hoi Eric,
>>
>> Wednesday, May 13, 2015, 11:25:55 PM, you wrote:
>>
>>> On Wed, May 13, 2015 at 5:02 PM, Hika van den Hoven <hikavdh at gmail.com> wrote:
>>>> I did some checking and I can't find a way to set a channel as HD or
>>>> SD. Only individual programs can be marked as HD by your grabber.
>>
>>> That's right.
>>
>>>> Which is weird. Why then that filter. and isn't everything on a
>>>> channel either SD or HD?
>>
>>> Not exactly.  An "HD" channel may broadcast in 1080i content that was
>>> upscaled from 480i.  Is that content HD or SD?  The listing (if
>>> correct) should list that program as SD even if it's on an "HD"
>>> channel.  The idea is that MythTV should be able to record SD
>>> broadcasts of SD content and do its own upscaling (if needed), but my
>>> experience has been that the listings are horribly inaccurate to the
>>> point of uselessness wrt determining which programs are actually HD.
>>> This was why I deleted all of the SD channels.  Too many listings
>>> listed HD programs as not-HD.
>>
>>> Eric
>>> _______________________________________________
>>
>> So, for the filter to work, you need different listings for the two
>> channels: For the HD channel with the <video><HD> tag's where
>> appropriate and without the tags for the SD channel.
>>
>> It would be nice if you could tag a channel as HD or SD and that
>> mythfilldatabase would ignore the HD tags for an SD channel! I'm now
>> thinking of a way to handle this in my grabber.
>
> Is this another instance of the need to switch some recent device drivers
> explicitly for HD or SD?  AIUI myth doesn't at present do that - see #12342.  I
> think I would expect an attempt to record HD without such a switch to fail
> because the PIDs were wrong, but...
>
Switching from SD to HD is a bit more fundamental than that, at least in the UK. 
Scanning with my SD USB tuners doesn't even recognise the existence of the HD 
multiplex.

I'm guessing the drivers have to switch to a whole different tuning mode to 
change between SD and HD and it is this that is currently not happening correctly.

Just sending a command "Tune to multiplex x, subchannel y" works between 
channels that are all SD, or all HD, but a little extra is needed changing 
transmission protocols - and recognising that you need to do so.

-- 

Mike Perkins