sotti
11-11-08, 03:32 PM
Okay so the issue revolves around black levels for the desktop and protected path rendering for blu-ray.
In XP HDMI and VGA the desktop is output at PC levels 0-255, that's what the display gets. So if your display calibrated for Video levels (set top boxes, DVD players, ect...) you'd want to use limited in the nvidia control panel for video levels, and everything would be fine.
In Vista VGA is still at PC Levels 0-255, but when you connect via HDMI the desktop is compressed to fit in the 16-235 Video Levels. This isn't inherently bad. For video that is not protected path the black level is in respect to the desktop so if the Display sees 16 when the dektop is 0, you just set the nvidia control panel to expad black to 0-255 and everything is fine.
The problem is Blu-Ray playback doesn't work in relation to the desktop setting it seems that it is always absolute. So because using HDMI adds a level of compression to ever other video source, regardless of what you set Blu-Ray playback is one step darker than everything else.
My hardware is an nforce8200 motherboard and I'm using the latest WHQL drivers w/ bothe XP and Vista (I've got dual boot setup).
So clearly this is a driver bug.
What I'd really like to know is if there is a registry hack to force the vista desktop back into 0-255 mode, because the bug only surfaces when the desktop is 16-235.
In XP HDMI and VGA the desktop is output at PC levels 0-255, that's what the display gets. So if your display calibrated for Video levels (set top boxes, DVD players, ect...) you'd want to use limited in the nvidia control panel for video levels, and everything would be fine.
In Vista VGA is still at PC Levels 0-255, but when you connect via HDMI the desktop is compressed to fit in the 16-235 Video Levels. This isn't inherently bad. For video that is not protected path the black level is in respect to the desktop so if the Display sees 16 when the dektop is 0, you just set the nvidia control panel to expad black to 0-255 and everything is fine.
The problem is Blu-Ray playback doesn't work in relation to the desktop setting it seems that it is always absolute. So because using HDMI adds a level of compression to ever other video source, regardless of what you set Blu-Ray playback is one step darker than everything else.
My hardware is an nforce8200 motherboard and I'm using the latest WHQL drivers w/ bothe XP and Vista (I've got dual boot setup).
So clearly this is a driver bug.
What I'd really like to know is if there is a registry hack to force the vista desktop back into 0-255 mode, because the bug only surfaces when the desktop is 16-235.