Dolby Vision now possible through MP4 Mux.

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RESET_9999
Posts: 2079
Joined: Mon Aug 05, 2019 7:12 pm

Re: Dolby Vision now possible through MP4 Mux.

Post by RESET_9999 »

No,
static DV metadata for a movie graded in the 1000-4000nits is not good and probably worse than static HDR10 because DV metadata is a lot more aggressive than HDR10 static curves.
For example if you have a 4000nits grade with a static 1000nits DV metadata. All the low-nits scenes will be darker and the brighter scenes will be more clipped than proper HDR10 metadata tone mapping curve. It's practically the same as making a DV P8 hybrid using two sources with different brightness, as shown here: https://www.youtube.com/watch?v=236athosits

Those movies with static DV are not done properly and should be avoided...
Trap is done properly because the content is below the DV 100nits floor (min)
staknhalo
Posts: 161
Joined: Sun Oct 11, 2020 12:05 am

Re: Dolby Vision now possible through MP4 Mux.

Post by staknhalo »

RESET_9999 wrote:
Tue Oct 29, 2024 3:55 pm
No,
static DV metadata for a movie graded in the 1000-4000nits is not good and probably worse than static HDR10 because DV metadata is a lot more aggressive than HDR10 static curves.
For example if you have a 4000nits grade with a static 1000nits DV metadata. All the low-nits scenes will be darker and the brighter scenes will be more clipped than proper HDR10 metadata tone mapping curve. It's practically the same as making a DV P8 hybrid using two sources with different brightness, as shown here: https://www.youtube.com/watch?v=236athosits

Those movies with static DV are not done properly and should be avoided...
Trap is done properly because the content is below the DV 100nits floor (min)
got it - so essentially as long as there's even just 'a little' data/grading in the L1 (as in native Trap and Longlegs) it's 'good' DV data - French Dredd still bad - thanks

Edit - I verify pre-aligned remuxes with the web source or different disc release just by quickly glancing at L1 which is why I wanted to be sure instead of aligning the web data to disc myself to be lazier lol :P
LV8HD
Posts: 35
Joined: Tue Jan 11, 2022 3:48 pm

Re: Dolby Vision now possible through MP4 Mux.

Post by LV8HD »

@RESET_9999 in the most recent update you introduced the possibility to measure brightness of an HDR10 video on a frame-by-frame basis, which, to me, seems the most correct approach. Does this mean the MadVR method is less accurate even with excluded letterboxes? does it work on a scene-by-scene basis?
RESET_9999
Posts: 2079
Joined: Mon Aug 05, 2019 7:12 pm

Re: Dolby Vision now possible through MP4 Mux.

Post by RESET_9999 »

LV8HD wrote:
Tue Oct 29, 2024 4:48 pm
@RESET_9999 in the most recent update you introduced the possibility to measure brightness of an HDR10 video on a frame-by-frame basis, which, to me, seems the most correct approach. Does this mean the MadVR method is less accurate even with excluded letterboxes? does it work on a scene-by-scene basis?
good catch haha. I didn't mention it in the release note because it's soooooo slow that it's unusable. I practically wasted my time on this code but it is indeed a frame by frame analysis / plotting. It uses the same script that generates the maxcll/fall stats in (7-2) (7-1).

Madvr analysis is also frame by frame but because I use Dovi_tool to plot the data, the graph is shot by shot. It's still 100% accurate but the values are rounded shot by shot. MadVR overall should be more accurate too since it measure pixels perceptually while the other script just measures the pixels as they are without any restriction.
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