Question for David on PP playback resolution

[Stephen Armour]

David, I noticed a somewhat strange thing in PP CS3, on a WIN7 x64 system.

When adjusting an nVidia NX8800 GTS card for another program (VirtualDub 1.9.8), I forced off the vertical sync in the 3D settings for CS4 (not installed on this particular ws) and then left it like that and returned to working on a PP CS3 project.

I had been looking at some CF video in VD, so had the CF output set to "FullQualityPlay.vbs" and normally this never plays well at the full resolution in PP3, so I have the Program window preview set to: Faster video decode, and the Disable preview mode playback turned off (deselected). Force YUV Destop playback was turned ON, and output was set to Desktop only, and Decode 4:2:2 as 4:4:4 is ON.

Now the strange part. Normally, this would playback at the 1/2 res, right?

But after turning off the vertical sync in the NVIDIA control panel (Manage 3D settings, Program Settings tab, Premiere CS4 Vertical sync to Force OFF), the Program window in PP3 is playing back very nicely at the highest quality, which I instantly noticed due to some text on the screen.

It seems it's much better than before and plays very nicely and in-sync at the highest decompress setting!

Excuse my ignorance, but can you explain this?

[Stephen Armour]

Forget it, I must be eating too much chocolate...

Now I can't recreate it, so it must have been a fluke. Sorry.

[David Newman]

No idea. :) Nvidia settings are confusing.

[Stephen Armour]

Ha! I'm not going crazy! When I turned off the "Force YUV playback", the quality returned! At least much better than with the YUV playback turned on.

Now that seems to make more sense. Since YUV playback is apparently not done right by the NVIDIA card, turning it off improves the perceived quality at 100% by reverting to RGB?

[David Newman]

That make more since, likely the GPU scaler is better on RGB than YUV.

[Stephen Armour]

The mystery deepens. Now, the YUV forced playback is much better! Argggg!

Something is switching back and forth when I mess with the NVIDIA settings. It somehow triggers PP's Program window back and forth.

Sigh. It's like production...one part skill, one part luck, one part magic...

[Richard Leadbetter]

Odd things can happen if you have two programs competing for the GPU's one hardware overlay, though I am not sure if that is what is happening here. Are you running these programs simultaneously or one after the other?

[Stephen Armour]

Originally Posted by Richard Leadbetter

Odd things can happen if you have two programs competing for the GPU's one hardware overlay, though I am not sure if that is what is happening here. Are you running these programs simultaneously or one after the other?

Actually, they were both loaded and I was just switching back and forth. But not running simultaneously. I'll try to find sometime tomorrow to play around a bit more. I noticed it also is now seeming to affect Media Player's sync. No time for serious sleuthing, but I'd like to know what's going on. It's always nice to be able to preview at the highest quality possible.

It doesn't affect our final output HD masters in any way, but it can affect our edit speeds at times.