So as we all know, Intel has a setting in their iGPU control panel which allows you to select the quantization range (limited or full) that is most appropriate for you display.
But as we all know, this setting doesn't actually do anything for most people. It seems to always use limited 16-235 range and the control panel option doesn't stick - it reverts back from full to limited on its own.
I find it hard to believe Intel would have such a long-standing bug in their drivers so I did some digging through the HDMI/CEA861 specs. Based on the specs, a device connected through HDMI that is using one of the pre-defined HDTV modes (1080i, 720p, etc.) is required to send limited range. The HDMI device is only allowed to send full-range if the display's EDID includes a "Video Capability Block" that containins the "Quantization Range Selectable" flag. This flag tells the player (iGPU in this case) that your display can handle both limited and full-range input.
My theory is that Intel is very strict about following these standards and therefore ignores the control panel setting when it doesn't find the above flag in the EDID.
Since I don't own any displays that enable the "Quantization Range Selectable" flag, I can't test my theory. I was hoping some users in this forum could help out.
To test if your display has the correct flag, examine your EDID using Entech MonInfo utilty:
http://www.entechtaiwan.com/util/moninfo.shtm (download link on the left side of page).
1) Run the Monitor Asset Manager (MonInfo) utility.
2) Select your monitor under the Display IDs section on the left. Should also say [Real-time ...] next to all your connected displays.
3) On the right side you will now get an "Asset Information" display listing information about your monitor.
4) You can save the report to upload here or just copy/paste it.
5) Look for an area like this:
CE video capability data
CE scan behavior......... Supports overscan and underscan
IT scan behavior......... Always underscanned
PT scan behavior......... Supports overscan and underscan
RGB quantization range... Selectable (via AVI YQ)
YCC quantization range... Selectable (via AVI YQ)
If your display has the RGB quantization range listed as "Selectable (via AVI YQ)", please try to toggle the Intel control panel quantization range setting and see if it has any effect. Also close the control panel and check if the setting "sticks" or reverts back to "limited" when you reopen it.
Thanks.
But as we all know, this setting doesn't actually do anything for most people. It seems to always use limited 16-235 range and the control panel option doesn't stick - it reverts back from full to limited on its own.
I find it hard to believe Intel would have such a long-standing bug in their drivers so I did some digging through the HDMI/CEA861 specs. Based on the specs, a device connected through HDMI that is using one of the pre-defined HDTV modes (1080i, 720p, etc.) is required to send limited range. The HDMI device is only allowed to send full-range if the display's EDID includes a "Video Capability Block" that containins the "Quantization Range Selectable" flag. This flag tells the player (iGPU in this case) that your display can handle both limited and full-range input.
My theory is that Intel is very strict about following these standards and therefore ignores the control panel setting when it doesn't find the above flag in the EDID.
Since I don't own any displays that enable the "Quantization Range Selectable" flag, I can't test my theory. I was hoping some users in this forum could help out.
To test if your display has the correct flag, examine your EDID using Entech MonInfo utilty:
http://www.entechtaiwan.com/util/moninfo.shtm (download link on the left side of page).
1) Run the Monitor Asset Manager (MonInfo) utility.
2) Select your monitor under the Display IDs section on the left. Should also say [Real-time ...] next to all your connected displays.
3) On the right side you will now get an "Asset Information" display listing information about your monitor.
4) You can save the report to upload here or just copy/paste it.
5) Look for an area like this:
CE video capability data
CE scan behavior......... Supports overscan and underscan
IT scan behavior......... Always underscanned
PT scan behavior......... Supports overscan and underscan
RGB quantization range... Selectable (via AVI YQ)
YCC quantization range... Selectable (via AVI YQ)
If your display has the RGB quantization range listed as "Selectable (via AVI YQ)", please try to toggle the Intel control panel quantization range setting and see if it has any effect. Also close the control panel and check if the setting "sticks" or reverts back to "limited" when you reopen it.
Thanks.