[vdr] Re: choosing a FF card

[Joerg Knitter <joerg.knitter@gmx.de>]

Tony Houghton wrote:
> In <420B3942.9070400@gmx.de>, Joerg Knitter wrote:
>
>
> > Sorry to disappoint you, but apart from Matrox cards, there is no way to 
> > output a video 1:1 i.e. without deinterlacing and with correct field-parity.
>
> What about FF and DXR3 cards? If they don't support parity, their
> deinterlacing filters (at least in the DXR3, because I haven't seen a FF
> card) must be very good. The main reason I replaced my DXR3 was because
> I generally watch more DivX than TV on my PC, and I couldn't always get
> it to scale correctly. Sound output was a bit weak too.
IMHO FF and DXR3 donīt need any deinterlacing because they have their 
own timer and can sync to a TV perfectly.

> The main problem IME is that while the clock in my G450 seems to be
> close enough to the broadcaster's clock to play video alone very
> smoothly while keeping it in sync with the TV output, my cheap sound
> card has a less accurate clock which drifts significantly from the video
> card's. I don't know whether things would be much better with a more
> expensive soundcard, but without perfect sync between the two cards I
> think I'm going to have to try to write a sound resampling filter for
> softdevice so the sound can be subtly adjusted to keep it in sync.
I donīt know how Matrox does the trick, but you need a reboot on windows 
if you activate the DVDMax feature which could mean that they change 
something in the DirectShow area.
On the other hand: How does the sync work in general? On Matrox cards, I 
would believe that the timing of the sound card is really taken, but the 
TV out frequency of the card is being adjusted slighlty to sync 
correctly to the sound. And I would say that this is exactly what ATI 
and nVidia cards are not able to do: The stay at their fixed TV out 
frequency and so are not able to keep in sync with the sound.

But there is still one question that remains on WinXP: AFAIK there is no 
possiblity to determine if the upper field or the lower field is being 
displayed. So how it it possible that you have settings like upper/lower 
field first on newer Matrox cards?

> BTW, I don't remember seeing an announcement about softdevice - I'm
> getting some emails very late though - but it now supports Matrox field
> parity in CVS. Nice work, Stefan.
Going to try this one also (even if I have a FF card) e.g. if I want to 
build a client PC without the limitations (OSD) of a DXR3, my FF once 
gets damaged or if I want to upgrade to a HDTV VDR :-)

With kind regards

Joerg