Dolby Vision now possible through MP4 Mux.

[floyd12]

Hello all,

I have a big doubt on something.

I managed to use (I think correctly) the quietvoid's and yusesope's tools to mux Web-DL DV metadata with Base layer HDR bluray remux for several titles.

Now I have the HDR Tenet Bluray Remux and the DV Web-DL version.
You probably know that the bluray version has the IMAX format ratio but the Web-DL version has 2.35 format ratio.

My question is, is there a way to do the same with different aspect ratio without distorting the director's vision?

I know it has already been discussed in this topic, and read something about L6 metadata etc... But it's complicated to understand exactly what is the precautions to take and the workflow, and I'm french so it's not helping

Can you please enlight me on this subject? Or indicate me the page on this topic where it would be explained?

Thank you very much.

[RESET_9999]

My question is, is there a way to do the same with different aspect ratio without distorting the director's vision?

you can do it by editing L5 but it won't be accurate especially if there are highlights in the imax area... see: https://screenshotcomparison.com/compar ... p?id=22977
IMAX metadata has pixels that the bluray doesnt have.

[Gatorman]

My question is, is there a way to do the same with different aspect ratio without distorting the director's vision?

you can do it by editing L5 but it won't be accurate especially if there are highlights in the imax area... see: https://screenshotcomparison.com/compar ... p?id=22977
IMAX metadata has pixels that the bluray doesnt have.

Will editing L5 per frame, e.g. (0,0,0,0) for IMAX that is full screen and (0,0,280,280) for 2.35:1, make the metadata accurate? I realize it's tedious. The last film I did this for had an editor json with over 125 lines.

[RESET_9999]

Will editing L5 per frame, e.g. (0,0,0,0) for IMAX that is full screen and (0,0,280,280) for 2.35:1, make the metadata accurate? I realize it's tedious. The last film I did this for had an editor json with over 125 lines.

sure but it's still not accurate because the L1/L2 metadata are generated by analyzing every pixel of each frame/shot. So mathematically, the metadata cannot be the same because 1 video has more pixels to analyze.
So in that case you are lying to your TV. DV is all about the most accurate tone mapping according to the metadata the TV receives.

[Gatorman]

sure but it's still not accurate because the L1/L2 metadata are generated by analyzing every pixel of each frame/shot. So mathematically, the metadata cannot be the same because 1 video has more pixels to analyze.
So in that case you are lying to your TV. DV is all about the most accurate tone mapping according to the metadata the TV receives.

Would it be more accurate/better to use madVR to generate an RPU from the non-DV blu-ray?

[RESET_9999]

Would it be more accurate/better to use madVR to generate an RPU from the non-DV blu-ray?

I think so unless it's a very bright HDR grade and that the L2 trim passes have a huge impact on the tone mapping.

[quietvoid]

Would it be more accurate/better to use madVR to generate an RPU from the non-DV blu-ray?

That would imply removing L2 trims, which isn't any better.

[stn17]

Does auto L5 work well enough in the latest Dolby tools? Playing around with madVR RPU injector, can't figure out how to manually L5 for a 4:3 movie that is presented in 16:9 with black bars on the side.

[RESET_9999]

Does auto L5 work well enough in the latest Dolby tools? Playing around with madVR RPU injector, can't figure out how to manually L5 for a 4:3 movie that is presented in 16:9 with black bars on the side.

if you're talking about my script, then yes it will work and you must use the Auto-L5 modes for 4:3 content because all the Manual-L5 modes were implemented for 16:9 content ( personal choice: since 4:3 UHD content is rare).
If you need to do more RPU editing, there's an RPU editor mode that allows you to do pretty much anything. (MODE.R ---> MODE.7= RPU Editor)

[johnjon94]

Would it be more accurate/better to use madVR to generate an RPU from the non-DV blu-ray?

I think so unless it's a very bright HDR grade and that the L2 trim passes have a huge impact on the tone mapping.

Would generating an RPU via madVR be considered 'fake' DV since its not official? I've been wondering how true madVR measurements are as compared to an official RPU from a WEB-DL.

[RESET_9999]

Would generating an RPU via madVR be considered 'fake' DV since its not official? I've been wondering how true madVR measurements are as compared to an official RPU from a WEB-DL.

No, it's not fake DV. It's truly dynamic with pixels measurement per frame/shot just like the Dolby Vision algo.
You can easily test it by delaying the RPU(which I did) and see the brightness changes in every scene cut just like DV.
see: https://screenshotcomparison.com/comparison/23824
even without L2 , it is surprisingly close to the original... FYI, this scene is 3600nits.

Fake DV = just a DV flag that triggers DV on your TV but no actual dynamic metadata.

[johnjon94]

Would generating an RPU via madVR be considered 'fake' DV since its not official? I've been wondering how true madVR measurements are as compared to an official RPU from a WEB-DL.

No, it's not fake DV. It's truly dynamic with pixels measurement per frame/shot just like the Dolby Vision algo.
You can easily test it by delaying the RPU(which I did) and see the brightness changes in every scene cut just like DV.
see: https://screenshotcomparison.com/comparison/23824
even without L2 , it is surprisingly close to the original... FYI, this scene is 3600nits.

Fake DV = just a DV flag that triggers DV on your TV but no actual dynamic metadata.

So in regards to IMAX films with no 'official' IMAX DV release, would it be better to run madVR to measure and generate the RPU rather than applying an RPU from a WEB-DL that isn't IMAX?

[RESET_9999]

So in regards to IMAX films with no 'official' IMAX DV release, would it be better to run madVR to measure and generate the RPU rather than applying an RPU from a WEB-DL that isn't IMAX?

well, it depends on how strong the L2 trim passes are.

I personally kept the IMAX web-dl (with lossless audio) because I prefer more pixels than a higher bitrate...
And Disney plus 16mb/s encodes are pretty good (or is it their BD encodes that suck?)

see:
https://screenshotcomparison.com/compar ... p?id=18914
https://screenshotcomparison.com/compar ... p?id=18884
https://screenshotcomparison.com/compar ... p?id=18895

[johnjon94]

So in regards to IMAX films with no 'official' IMAX DV release, would it be better to run madVR to measure and generate the RPU rather than applying an RPU from a WEB-DL that isn't IMAX?

well, it depends on how strong the L2 trim passes are.

I personally kept the IMAX web-dl (with lossless audio) because I prefer more pixels than a higher bitrate...
And Disney plus 16mb/s encodes are pretty good (or is it their BD encodes that suck?)

see:
https://screenshotcomparison.com/compar ... p?id=18914
https://screenshotcomparison.com/compar ... p?id=18884
https://screenshotcomparison.com/compar ... p?id=18895

I meant in regards to movies that don't have IMAX DV WEB-DL releases but have an IMAX HDR WEB-DL, like Spider-Man Far From Home. I am the same as you when it comes to the Disney+ IMAX WEB-DL's. I keep the originals with the lossless BluRay audio.

[RESET_9999]

I meant in regards to movies that don't have IMAX DV WEB-DL releases but have an IMAX HDR WEB-DL, like Spider-Man Far From Home. I am the same as you when it comes to the Disney+ IMAX WEB-DL's. I keep the originals with the lossless BluRay audio.

Well, I cant give you an exact answer, too many variables but with a maxcll of 9978nits, the L2 trims are probably strong but from my test with Spears and munsil 10k nits (and this is my opinion), the L1 metadata has a bigger impact than L2.
And even without L2, DV is much better than HDR10 when it comes to bright HDR grade.
I personally only do hybrid remux when both videos have the same aspect ratio.