[mythtv-users] Seemingly many unusable deinterlace methods.

[Paul Gardiner]

Mark Kendall wrote:
> 2008/12/29 Paul Gardiner <lists at glidos.net>:
>> Mark Kendall wrote:
>>> 2008/12/29 Paul Gardiner <lists at glidos.net>:
>>>> I'm using opengl rendering, and trying to select
>>>> the "Interlaced 2x (HW)" deinterlacer, but I get an
>>>> error:
>>>>
>>>> Failed to approve 'opengldoubleratefieldorder' deinterlacer.
>>>>
> 
>>> Paul - are you on fixes or trunk?
>> Hmmm, sorry, I have to admit I don't really know... well
>> certainly not on trunk. I'm using Minimyth, and my look at
>> the source was just what I downloaded from the MythTV site,
>> so probably just the snapshot of the release of v21.
>>
> 
> OK - firstly, that log message will often appear when in live tv and
> the video player tries to set the deinterlacer before the final
> playback profile/renderer has been fully initialised. Admittedly it's
> confusing - and still in trunk I think. To check whether your
> deinterlacer of choice is subsequently approved, you need to run with
> some extra logging (-v playback).

Ok, thanks, I can give that a try. As far as I can see I get no
change over "none". I'm outputting PAL into a PAL TV via the
VGA port using a conversion circuit to Scart. The problem I'm
trying to fix is that I randomly get two modes of playback:
sometimes more or less perfect playback, sometimes loads of
interlace combs when anything moves. It's not a big problem, because
hitting pause a few times changes from one mode to the other
and then it tends to stick in the one mode from then on.

> Secondly, even if it does approve that particular deinterlacer, you
> probably will still notice interlacing artifacts. It's designed not to
> deinterlace (if that makes sense!) but to try and present interlaced
> material on interlaced displays so that the tv can do the
> deinterlacing.

Yeah, that's exactly what I'm after. As far as I can reason, the use
of that deinterlacer should mean my TV will get the correct interlaces
independently of which vsync the decompressed frames get synchronised
to.

> and finally, if that's a minimyth installation on a via board,  you're
> not going to get a lot of mileage out of opengl playback anyway :)

I do have a VIA board, but the current experimentation is with an
old Radeon 9000 using the open source "radeon" driver. Amazingly
they have implemented fragment shading and opengl seems to work fine.
I stumbled on it only because of the bug that makes XVMC fallback to
opengl. But now I know I can use opengl, I'm really hoping to use
the field-order deinterlacer because it could get rid of my last
real problem.

Cheers,
	Paul.