[mythtv-users] Frontend Lockups

Frank Merrill fmerrill1 at gmail.com
Fri Feb 5 14:21:44 UTC 2010

On Fri, Feb 5, 2010 at 1:06 AM, Phil Wild <philwild at gmail.com> wrote:
>> A few things.  First, the chart on that page says that the 9500 will
>> do 1080i de-interlacing using Advanced 2X but with possible stuttering
>> on occasion.
>> To do any 2x interlacing, your display has to be able to do double the
>> refresh rate to accommodate a doubled frame-rate, so, for example, if
>> your currently set refesh rate is at 60Hz, can your display do 120Hz?
>> If not, then you won't be able to use the 2X de-interlacers. (the card
>> can do them, but the display also has to be able to)
>> I suspect your 1920x1080 display would be able to do it, but you may
>> need to adjust your Nvidia-Settings and see what refresh rate you have
>> set in there now.
>> You also should check the display specs to see if it will do double
>> that rate or not.
>> Is it really a 1920x1080 display, or is that just a resolution the
>> display says it will accept?
> I don't believe this is true. A 60Hz 1080i video stream is 30 frames
> of odd lines (540 lines) interlaced with 30 frames of even lines (540
> lines) every second.
> I am not sure what exactly advanced 2x does to create the final
> stream, but the final stream is 1080p at 60Hz, not 120Hz.
> Happy to be corrected if I am wrong though...

No, you are right, I worded it poorly and I shouldn't have used 60Hz
as an example, as in reality 1080i is broadcast between 25 and 30
frames per second, and the 2X de-interlacers double the frame rate, so
a 25fps or 30fps stream would be doubled and require a 50Hz or 60Hz
refresh rate.
My point was mainly that Advanced 2X requires the display to be able
to accept double the frame rate of the input content.


More information about the mythtv-users mailing list