Dolby Vision now possible through MP4 Mux.

[speeddemon]

Does anyone know why more playback devices aren't capable of utilizing the 100-nit L2 trim for playback on SDR devices?
I've noticed that Apple, Google, and Amazon devices don't use the 100-nit L2 trim for playback on an SDR device even though all of them are Dolby Vision compatible. I'm following @RESET_9999's tutorial for using the 100-nit trim to create an SDR encode (via Resolve and Staxrip). Thanks!

AFAIK, the Fire Stick tv 4k and sony x700/x800m2 can. Not sure if it does its own tone mapping internally or if it's using the trim pass though. That would be easy to test with a capture card.

I haven't tested Apple/Amazon/Google devices with a capture card, but I have hooked them all up to a calibrated screen, compared, and the differences were significant. They all appeared to be doing their own tone mapping. I haven't tested this in a long time though so it's possible some/all have improved.

I also never tested from a Sony/Oppo blu-ray player.

I feel like it's an interesting scenario though for people with projectors.

[RESET_9999]

I haven't tested Apple/Amazon/Google devices with a capture card, but I have hooked them all up to a calibrated screen, compared, and the differences were significant. They all appeared to be doing their own tone mapping. I haven't tested this in a long time though so it's possible some/all have improved.

I also never tested from a Sony/Oppo blu-ray player.

I feel like it's an interesting scenario though for people with projectors.

With Windows 10/11 mediaplayer, even the 600nits trim is used for SDR/HDR and the 100nits trim has very little effect(at least on the test file i used).

[Rainbaby]

I haven't tested Apple/Amazon/Google devices with a capture card, but I have hooked them all up to a calibrated screen, compared, and the differences were significant. They all appeared to be doing their own tone mapping. I haven't tested this in a long time though so it's possible some/all have improved.

I also never tested from a Sony/Oppo blu-ray player.

I feel like it's an interesting scenario though for people with projectors.

With Windows 10/11 mediaplayer, even the 600nits trim is used for SDR/HDR and the 100nits trim has very little effect(at least on the test file i used).

A common misconception is the confusion between DV display management and the meaning of "SDR" in the context of display operating modes. While in the context of DV, "SDR" usually refers to a 100-nit BT.709 Gamma 2.4 target display, the latter only roughly denotes the display is using a SDR gamma. In this scenario, the DV target brightness can be just any value and is typically greater than 100 nits. The final trim used for your display depends on the target brightness and available trims in metadata and is usually interpolated values from trims for lower and higher target brightness.

You may want to find out the target brightness of your current display, I made a test pattern for a quick check.
Download: https://mega.nz/file/XEQRyC6S#PIoiGsnCx ... 3j8AbPjmSQ

Check the grayscale in the center of the screen, visually identify the point where the grayscale stops (start turning into white), and use the logarithmic scale below to determine the approximate target brightness. For example, the screenshot below means a target brightness of 500-nit.

It only works in players with DV display management support, so players like mpv that only composes base layer will not work, they will just show a full grayscale.
On Windows, you will get a target brightness of 270-nit in SDR mode and 1500-nits in HDR mode if your display doesn't provide any useful data about this through EDID.
On macOS, you should not use any reference mode with locked brightness, it will just bypass display management.
The target brightness may change with user tunable display parameters like brightness setting and DV mode, and other parameters such as ambient brightness. And it doesn't mean your display is actually operating with that brightness (although it would better be).

[RESET_9999]

Oh right, in DV playback, I knew that all the trims worked together in interpolation but I didn't know it was the same in SDR playback.
thanks for the info.

[nateify]

Hello, I had a question based on some posts around page 595 seen here about using Dovibaker for FEL to HDR10+P8 baking: viewtopic.php?p=140818&sid=fb796c7eeede ... 85#p140818

I am trying to figure out how to accurately determine the value to set for "-max-cll" in the x265 encoder. I see some discussion on that page but I'm still unsure.

My specific example is using Dovibaker on Total Recall P7 FEL ST-DL MKV, converting the FEL RPU to p8.1 RPU, then injecting the p8.1 RPU into encoded+baked HDR10 stream finally for playback on a device and TV which support DV P8.1.

When I extract the RPU and get a summary from dovi_tool, this is shown:

Code: Select all

Summary:
  Frames: 7203
  Profile: 7 (FEL)
  DM version: 1 (CM v2.9)
  Scene/shot count: 28
  RPU mastering display: 0.0001/1000 nits
  RPU content light level (L1): MaxCLL: 708.26 nits, MaxFALL: 25.98 nits
  L6 metadata: Mastering display: 0.0001/1000 nits. MaxCLL: 0 nits, MaxFALL: 0 nits
  L2 trims: 100 nits, 600 nits, 1000 nits

Is the L1 or L6 value what I am looking for here?

Additionally, I found a Github thread here for Dovibaker https://github.com/erazortt/DoViBaker/i ... 1257758611

Where the original author made the following comment: "To find the actual values for max-cll of your created stream you can use MaxCllFind. To do this put the command ConvertToRGB64() after the call to DoViBaker. As the very last command in the script put the call to MaxCllFind()."

When I do this I find this by the final frame the values are: MaxCLL: 3870.62 and MaxFALL: 84.1747 this seems quite different than what dovi_tool tells me and I did not find a lot of discussion on this method and not sure if it is even relevant to my use case.

One more bonus question if anyone has any input. On a private tracker in a discussion someone mentioned AviSynth with MapNLQ plugin is preferred to DoViBaker, has anyone here tested this or have any more info on it and what tangible benefits it has?

[hugard]

Hey @RESET_9999 , Firstly thanks for that awesome spreadsheet of yours. It has helped me understand a lot about how DV works. I have a question. For the UHD BD movies where the brightness/details get expanded via the FEL layer, would those movies look dimmer or have slightly less detail even if I play them in just HDR10? Or is this a problem only when I try to play them in DV with a device that can't decode FEL? I would assume that they would look dimmer or have slightly less detail even if I play them in just HDR10. If so, why do studios do this? They're essentially downgrading the HDR10 output and fixing things in the DV output through the FEL. Ideally the HDR10 version should be the best it can possibly be and DV should just be an improvement over it, right?

[RESET_9999]

When I do this I find this by the final frame the values are: MaxCLL: 3870.62 and MaxFALL: 84.1747 this seems quite different than what dovi_tool tells me and I did not find a lot of discussion on this method and not sure if it is even relevant to my use case.
One more bonus question if anyone has any input. On a private tracker in a discussion someone mentioned AviSynth with MapNLQ plugin is preferred to DoViBaker, has anyone here tested this or have any more info on it and what tangible benefits it has?

Yes, I would use the values from the dovi Level 1 (MaxCllFind).
I tried MapNLQ and didn't notice any benefits. The speed was exactly the same as the dovi_baker (+prefetch)

Hey @RESET_9999 , Firstly thanks for that awesome spreadsheet of yours. It has helped me understand a lot about how DV works. I have a question. For the UHD BD movies where the brightness/details get expanded via the FEL layer, would those movies look dimmer or have slightly less detail even if I play them in just HDR10? Or is this a problem only when I try to play them in DV with a device that can't decode FEL? I would assume that they would look dimmer or have slightly less detail even if I play them in just HDR10. If so, why do studios do this? They're essentially downgrading the HDR10 output and fixing things in the DV output through the FEL. Ideally the HDR10 version should be the best it can possibly be and DV should just be an improvement over it, right?

It's only a problem when you try to play those FEL movies in DV on a device that can't process the EL. HDR10 will be as intended.

why do studios do this?

viewtopic.php?p=137560#p137560

[DjObama]

Hi,
Is it possible to add lossless (DTS-HD MA, TrueHD) conversions to FLAC to mp4 workflows?
If not then how can I add flac tracks to p7 DT-DL MP4s created using Dovi scripts?

[RESET_9999]

Hi,
Is it possible to add lossless (DTS-HD MA, TrueHD) conversions to FLAC to mp4 workflows?
If not then how can I add flac tracks to p7 DT-DL MP4s created using Dovi scripts?

Why Flac? You have to give me a good reason because there's already an option for LPCM.

or you can look at this very old tutorial(@yusesope) to make mp4 with flac audio:
https://mrmc.tv/forum/viewtopic.php?f=1 ... &start=310

[kazuma]

i see sometimes hybrid versions of movies that have no DV on the original disc. Are the publishers adding fake DV on this torrents? why is a hdr10 movie hybrid?

[speeddemon]

I haven't tested Apple/Amazon/Google devices with a capture card, but I have hooked them all up to a calibrated screen, compared, and the differences were significant. They all appeared to be doing their own tone mapping. I haven't tested this in a long time though so it's possible some/all have improved.

I also never tested from a Sony/Oppo blu-ray player.

I feel like it's an interesting scenario though for people with projectors.

With Windows 10/11 mediaplayer, even the 600nits trim is used for SDR/HDR and the 100nits trim has very little effect(at least on the test file i used).

A common misconception is the confusion between DV display management and the meaning of "SDR" in the context of display operating modes. While in the context of DV, "SDR" usually refers to a 100-nit BT.709 Gamma 2.4 target display, the latter only roughly denotes the display is using a SDR gamma. In this scenario, the DV target brightness can be just any value and is typically greater than 100 nits. The final trim used for your display depends on the target brightness and available trims in metadata and is usually interpolated values from trims for lower and higher target brightness.

You may want to find out the target brightness of your current display, I made a test pattern for a quick check.
Download: https://mega.nz/file/XEQRyC6S#PIoiGsnCx ... 3j8AbPjmSQ

Check the grayscale in the center of the screen, visually identify the point where the grayscale stops (start turning into white), and use the logarithmic scale below to determine the approximate target brightness. For example, the screenshot below means a target brightness of 500-nit.

It only works in players with DV display management support, so players like mpv that only composes base layer will not work, they will just show a full grayscale.
On Windows, you will get a target brightness of 270-nit in SDR mode and 1500-nits in HDR mode if your display doesn't provide any useful data about this through EDID.
On macOS, you should not use any reference mode with locked brightness, it will just bypass display management.
The target brightness may change with user tunable display parameters like brightness setting and DV mode, and other parameters such as ambient brightness. And it doesn't mean your display is actually operating with that brightness (although it would better be).

Since SDR displays are not going to be capable of TV-led Dolby Vision, how would they handle communicating their luminance capabilities to the player allowing player-led LLDV to interpolate L2 trims and output anything other than 100-nit? It seems to me like the safe bet would be for all players to just output the 100-nit SDR L2 trim if/when the display device interpreted as or set to SDR-only. Am I misunderstanding?

[DjObama]

Hi,
Is it possible to add lossless (DTS-HD MA, TrueHD) conversions to FLAC to mp4 workflows?
If not then how can I add flac tracks to p7 DT-DL MP4s created using Dovi scripts?

Why Flac? You have to give me a good reason because there's already an option for LPCM.

or you can look at this very old tutorial(@yusesope) to make mp4 with flac audio:
https://mrmc.tv/forum/viewtopic.php?f=1 ... &start=310

Flac will be much smaller in size than LPCM, so less bandwidth used when plaing. Sometimes DV UHD movies stutter (nothing major, like 1-2 times per viewing) for me when played from external HDD, I suppose with flac it would be happening less. Especially if you'd add the option to convert to 16 bit flac instead of 24 bit. I think 16 is plenty enough. Dts-hd ma converted to 16 bit flac often take 1/4th of its original size, often less than DD+ @1,5mbps. And compared to eac3 flac is still a lossless file format = piece of mind for us audio- and vision nerds

[hugard]

i see sometimes hybrid versions of movies that have no DV on the original disc. Are the publishers adding fake DV on this torrents? why is a hdr10 movie hybrid?

They are taking the DV metadata from DV WEB-DL releases and adding it to the HDR10 files ripped from the UHD BD. This should only be done when the DV WEB-DL and UHD BD are derived from the same master grade. Also, the syncing needs to be done properly. Otherwise, it can create problems. Even the biggest groups make mistakes sometimes. For this reason, I generally avoid hybrid DV releases.

[RESET_9999]

Flac will be much smaller in size than LPCM, so less bandwidth used when plaing. Sometimes DV UHD movies stutter (nothing major, like 1-2 times per viewing) for me when played from external HDD, I suppose with flac it would be happening less. Especially if you'd add the option to convert to 16 bit flac instead of 24 bit. I think 16 is plenty enough. Dts-hd ma converted to 16 bit flac often take 1/4th of its original size, often less than DD+ @1,5mbps. And compared to eac3 flac is still a lossless file format = piece of mind for us audio- and vision nerds

Which playback device do you use? I just tried on my C2 and there's no direct play for FLAC/PCM, all I got was PLEX converting to DDP7.1 which is identical to my script.

[DjObama]

Flac will be much smaller in size than LPCM, so less bandwidth used when plaing. Sometimes DV UHD movies stutter (nothing major, like 1-2 times per viewing) for me when played from external HDD, I suppose with flac it would be happening less. Especially if you'd add the option to convert to 16 bit flac instead of 24 bit. I think 16 is plenty enough. Dts-hd ma converted to 16 bit flac often take 1/4th of its original size, often less than DD+ @1,5mbps. And compared to eac3 flac is still a lossless file format = piece of mind for us audio- and vision nerds

Which playback device do you use? I just tried on my C2 and there's no direct play for FLAC/PCM, all I got was PLEX converting to DDP7.1 which is identical to my script.

LG B8. Flac works in mp4/mkv files in SDR. I don't know about DT-DL mp4s, for now I'm having troubles creating such files. Maybe you have a DV DT-DL sample with flac for testing?