Doom9's Forum - View Single Post - madVR - high quality video renderer (GPU assisted)

ashlar42 · 26th September 2018, 17:16

Just to see if I understood things discussed in the last few pages correctly... (I currently still use a Kuro plasma, so I can't test HDR).

madVR offers the option to tone map HDR. This is of great use for people with projectors, as those are quite limited in the amount of nits they can produce.
OLEDs could benefit as well, as they are less capable than LCDs in this regard (nits produced), but, at least for LGs, there's no way to deactivate internal HDR tonemapping without going SDR (thus limiting panel light output below HDR requirements).

Correct so far?

madshi states that TVs are not "smart" enough to deactivate their internal tonemapping routines. What I don't understand is: if madVR already outputs a tone mapped picture and the user has inputted correct peak brightness values for their TV... what would the TV tone map for? Am I correct in assuming that the problem stems from OLED not having a peak brightness "per se" but a peak brighness depending on highlights size? In madVR HDR configuration tab there's just a single "target peak nits" value to input.

If one checks measurements such as these: https://www.rtings.com/tv/reviews/lg/c8#comparison_1675, it's pretty clear that the peak brighness varies immensely according to the zone to be displayed at high nits, due to ABL. As such, and given the current single value input available, I doubt that madVR can provide a better tone mapping results than the internal system in an OLED screen. Am I wrong/missing something? Is there a chance we could have a more flexible configuration for the target peak nits, in order to better serve OLED screens?

Thanks for reading and for answers. And thanks forever to madshi for all he does for us HTPC lovers.

26th September 2018, 17:16	#52759 \| Link
ashlar42 Registered User Join Date: Jun 2007 Posts: 656	Just to see if I understood things discussed in the last few pages correctly... (I currently still use a Kuro plasma, so I can't test HDR). madVR offers the option to tone map HDR. This is of great use for people with projectors, as those are quite limited in the amount of nits they can produce. OLEDs could benefit as well, as they are less capable than LCDs in this regard (nits produced), but, at least for LGs, there's no way to deactivate internal HDR tonemapping without going SDR (thus limiting panel light output below HDR requirements). Correct so far? madshi states that TVs are not "smart" enough to deactivate their internal tonemapping routines. What I don't understand is: if madVR already outputs a tone mapped picture and the user has inputted correct peak brightness values for their TV... what would the TV tone map for? Am I correct in assuming that the problem stems from OLED not having a peak brightness "per se" but a peak brighness depending on highlights size? In madVR HDR configuration tab there's just a single "target peak nits" value to input. If one checks measurements such as these: https://www.rtings.com/tv/reviews/lg/c8#comparison_1675, it's pretty clear that the peak brighness varies immensely according to the zone to be displayed at high nits, due to ABL. As such, and given the current single value input available, I doubt that madVR can provide a better tone mapping results than the internal system in an OLED screen. Am I wrong/missing something? Is there a chance we could have a more flexible configuration for the target peak nits, in order to better serve OLED screens? Thanks for reading and for answers. And thanks forever to madshi for all he does for us HTPC lovers.