Progessive PAL (was Re: [mythtv-users] TV Output)
Julian Edwards
ed at julian-edwards.com
Sat Jan 1 10:03:45 EST 2005
>> >ModeLine "720x576pali" 13.875 720 744 808 888 576 581 586 625 -hsync
>> >-vsync interlace
>>
>> I don't suppose you have a simliar spec for a progressive PAL image do
>> you? (I have the Key Digital VGA to Component adapter)
>>
>> I generated one based off a Powerstrip mode to get 1024x576 which gives
>> an awesome picture, but I'm not sure whether it's entirely in spec as
>> the *TV*'s input identifier is flashing in the corner, which apart from
>> being really annoying probably means that the signal is not entirely in
>> spec. (The *TV*'s a Panasonic 36PD30 if it makes any difference)
>
>Progressive PAL is exactly the same as regular PAL, but you need to drop
>the "interlace" in that line. Simple as that.
>
>Kind regards,
>
>Mark Wormgoor
Hi
Just got back after the Christmas break and took a look at this. The
problem with your suggestion is that the frame rate goes down to 25Hz,
which the TV will not scan.
I did a little research some time ago and I don't think there's an
"official" progressive PAL specification but what I found indicates that
the horizontal frequency increases from 15.625kHz to 31.25kHz - ie. it
doubles.
The mode I mentioned above does indeed result in a 31.25 horizontal
frequency and thus a 50Hz frame rate:
Modeline "1024x576p" 43.500 1024 1128 1232 1392 576 577 580 625
-hsync -vsync
(In case anyone's wondering, I do have a bunch of 720x576p modelines as
well but absolutely none of them work, hence the choice of horizontal
resolution.)
I tried your interlaced PAL modeline on my TV and it produces a fine
picture but I still get my problem with the flashing input identifier.
When using the interlaced component output from the DVD player it's not
there so I think I've got a problem with the Key Digital converter
somewhere, maybe with the sync signal. :(
Is anyone else in PAL land using one of these converters with a
Panasonic TV?
J.
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