Apparently, you did read the pursuit instructions, so good job doing a pursuit camera via hand-waved smartphone! (For other readers, see Easy Pursuit Camera 101 Instructions
) -- the hand-wave iPhone video camera following the UFOs on the http://www.testufo.com/ghosting
Screenshot of one of the better single-frame-steps (the , and . keys to single framestep a YouTube)
TestUFO Without FreeSync at 0:02
TestUFO With FreeSync (Full framerate, GSYNC Compatible + Windowed Mode) at 0:17
No, I can confirm it's not a hidden DRM-protected protocol.
The same thing actually happens when you use an AMD card too (depending on how the drivers are configured, you MAY
have to go into full screen mode with "chrome --disable-gpu-vsync" to properly trigger the AMD FreeSync into working with TestUFO on AMD cards when the browser is running in full screen mode).
It's simply the monitor automatically using a different Overdrive Gain setting when FreeSync is enabled (rather than disabled), or the existence of Dynamic Overdrive. Since the AW2518H doesn't have dynamic overdrive (read Why Variable Overdrive is needed for Good Variable Refresh Rate
), I think it's simply changing to a more optimal overdrive setting whenever FreeSync is enabled.
Even for non-dynamic overdrive, some manufacturers keeps their better overdrive settings only for FreeSync mode, so everything looks crappy-ghosty when FreeSync is turned off but looks much better when FreeSync is enabled.
On some monitors, via Factory Menu or Service Menu, I am able to adjust an Overdrive Gain setting between value 0x00 through 0x80 which produces the same effect in non-FreeSync modes (both image #1 and #2). Overdrive Gain is a generic setting built into many panels. Simple few-setting overdrive adjustments are often mapping to hardcoded Overdrive Gain settings.
Now, two theories:
(A) That there is an Overdrive Gain setting that is accessible by DDC.
(B) That there is the use of software-based (GPU shader) overdrive similar to the old ATI Radeon overdrive
To get in-between values (e.g. between "AMA OFF", "AMA High", "AMA Premium") require hacking around an Overdrive Gain setting.
For some monitors, sometimes I have to run Entech SoftMCCS and try to find the hidden DDC/CI adjustment (VCP command) that corresponds to an Overdrive Gain, but often that setting is not even accessible except to a firmware engineer. Occasionally one can hunt down a hidden VCP command by dumping all 256 VCP settings, changing the generic overdrive setting, then dumping all 256 VCP codes again to see what changed, and then figure out if I can access intermediate (in-between) overdrive settings that way.
I haven't found any settings accessible on AW2518H, but if there is one, maybe NVIDIA drivers is adjusting that DDC command. It would be an unlocked command if it exists. But usually most monitors are simply choosing a different Overdrive Gain default (a hex number between 0x00 thru 0x80 .... or in decimal, a number between 0 and 128).
Try downloading Entech Taiwan SoftMCCS
1. Disable the GSYNC Compatible checkbox
2. Launch SoftMCCS and then dump all 256 values and then copy-paste log to Notepad, save as .txt file. Quit SoftMCCS.
3. Enable the GSYNC Compatible checkbox
4. Launch SoftMCCS and then dump all 256 values and then copy-paste log to Notepad, save as .txt file. Quick SoftMCCS.
5. Run a diff utility on the two text files to see which VCP command changed.
6. Now try manually commanding the monitor to that specific VCP register using the "Command-line Editor" to send a custom datagram.
For example, VCP 0x10 is brightness. The first byte 0x03 is "Send Command". So telling the monitor to set Brightness OSD to a setting of 64 (hex 0x40), requires sending this four hex byte sequence: 03 10 00 40
0x03 - Send command
0x10 - The VCP command number for Brightness
0x00 - High byte of new brightness setting for monitor OSD
0x40 - Low byte of new brightness setting for monitor OSD.
So theoretically, you discover that enabling the checkbox for GSYNC Compatible, you observe a weird number change at 0xEF or 0xEC when you try to diff the two text files.
Then you'd try testing it (Change "EF" to the value or values you discover has changed):
03 EF 00 10
03 EF 00 20
03 EF 00 30
03 EF 00 40
To test four different "Overdrive Gain" settings (if, theoretically "Overdrive Gain" mapped to VCP command 0xEF).
Have a second screen ready (multimonitor, or laptop screen). Be prepared to factory reset it with a second screen, of a bad VCP command causes your monitor to go on the fritz (e.g. command that accidentally turns off backlight, for example). So keep that backup of all 256 VCP commands handy so you can write the correct values back later if need be...
Now, if you wanted to write a computer program that does this, you'd obviously use the SetVCPFeature()
API and/or the GetVCPFeatureAndVCPFeatureReply()
API available in Microsoft Windows. That is, if you were a software developer that wanted to remotely operate (via PC program) the monitor's own main OSD menu / hidden service menu / factory menu adjustments. Sometimes some monitor menus are completely inaccessible via VCP
For Linux use the ddcutil
code (or see its source code).
DDC = Display Data Channel (a wire on a VGA pin, on an HDMI cable, on a DVI cable, or a micropacket on DVI cable)
CI = Command Interface
DDC/CI = Display Data Channel / Command Interface
VESA = that standards organization
MCCS = Monitor Control Command Set
VCP = Virtual Control Panel (a method of PC controlling the monitor's menus in a hidden way)
Links to VESA docs
VESA MCCS Spec Version 2.2a