Pass over HDR10+ and Dolby Vision information?

[ShortKatz]

Now that HandBrake finally has a first 10-bit pipeline, I was experimenting with converting some HDR movies. For regular HDR10 this is relatively easy. You just need to read out the HDR values with e.g. MediaInfo and than add the --master-display and --max-cll values in HandBrakes additional option box.
But, how would I do this with dynamic metadata from HDR10+ and Dolby Vision sources?

[quietvoid]

For HDR10+ you can extract to JSON using https://github.com/quietvoid/hdr10plus_parser
And then feed the JSON to x265: https://x265.readthedocs.io/en/maste...on-dhdr10-info

For Dolby Vision, same principle: https://github.com/quietvoid/dovi_tool#extract-rpu
Feed to x265 with: https://x265.readthedocs.io/en/maste...lby-vision-rpu
Also have to specify the profile.

You'll need to figure out what profile your devices are compatible with, most likely converting to profile 8.1 is fine for most cases.
However this does not support cropped Dolby Vision encodes out of the box just yet, a modification to the code is necessary to override the metadata.

[Lollaskates]

Originally Posted by quietvoid

For HDR10+ you can extract to JSON using https://github.com/quietvoid/hdr10plus_parser
And then feed the JSON to x265: https://x265.readthedocs.io/en/maste...on-dhdr10-info

For Dolby Vision, same principle: https://github.com/quietvoid/dovi_tool#extract-rpu
Feed to x265 with: https://x265.readthedocs.io/en/maste...lby-vision-rpu
Also have to specify the profile.

You'll need to figure out what profile your devices are compatible with, most likely converting to profile 8.1 is fine for most cases.
However this does not support cropped Dolby Vision encodes out of the box just yet, a modification to the code is necessary to override the metadata.

Sorry, new to handling DV - Ive got a DV profile 7 MKV , (BL+EL+RPU) that i'm trying to encode with x265. In your instructions above, you mention extracting the RPU and then feeding it to x265.

Am I extracting the RPU as-is and then feeding it to x265 and specifying profile 8.1? or am I using that same tool to convert the RPU from profile 7 to profile 8.1 and then feeding it to x265 while specifying profile 8.1?

Thanks

[ShortKatz]

Originally Posted by quietvoid

For Dolby Vision, same principle: https://github.com/quietvoid/dovi_tool#extract-rpu
Feed to x265 with: https://x265.readthedocs.io/en/maste...lby-vision-rpu
Also have to specify the profile.

May I ask a question to this. I now extracted the RPU using

ffmpeg -i input.mkv -c:v copy -vbsf hevc_mp4toannexb -f hevc - | dovi_tool extract-rpu - -o RPU.bin

This worked nicely and gave me a 90MB file.
But how do I get the RPU into my encoded video?

First, I have tried it in HandBrake directly (which would be the perfect way). I've added

vbv-bufsize=160000:vbv-maxrate=160000:dolby-vision-profile=8.1:dolby-vision-rpu=/Filepath/RPU.bin

as additional options. But this did not work because of:

encx265: unknown option 'dolby-vision-rpu'

Then I've tried to first encode the video with HandBrake and then inject the RPU back into the final video with:

ffmpeg -i video.m4v -c:v copy -c:a copy -vbsf hevc_mp4toannexb -f hevc - | dovi_tool inject-rpu -i - --rpu-in /Filepath/RPU.bin -o final.mp4

But this did not work because of:

Error: RpuInjector: Must be a raw HEVC bitstream file

[quietvoid]

Originally Posted by ShortKatz

May I ask a question to this. I now extracted the RPU using

ffmpeg -i input.mkv -c:v copy -vbsf hevc_mp4toannexb -f hevc - | dovi_tool extract-rpu - -o RPU.bin

This worked nicely and gave me a 90MB file.
But how do I get the RPU into my encoded video?

First, I have tried it in HandBrake directly (which would be the perfect way). I've added

vbv-bufsize=160000:vbv-maxrate=160000:dolby-vision-profile=8.1:dolby-vision-rpu=/Filepath/RPU.bin

as additional options. But this did not work because of:

encx265: unknown option 'dolby-vision-rpu'

Then I've tried to first encode the video with HandBrake and then inject the RPU back into the final video with:

ffmpeg -i video.m4v -c:v copy -c:a copy -vbsf hevc_mp4toannexb -f hevc - | dovi_tool inject-rpu -i - --rpu-in /Filepath/RPU.bin -o final.mp4

But this did not work because of:

Error: RpuInjector: Must be a raw HEVC bitstream file

x265 supposedly only supports RPU files from CLI, so if Handbrake is using the library it might not be able to.
I think I've seen people use ffmpeg, but I'm not sure if it actually works.

For injecting, you need to be using the raw bitstream, it can't be piped.
So demux first, inject, remux. You also can't output in mp4, it'll just be HEVC with no container.

[benwaggoner]

And note a lot of Dolby Vision devices don't support Profile 8.1, and most sources aren't in that either. Converting between DoVi versions requires a full tone remapping, beyond the abilities of something like Handbreak.

[quietvoid]

Originally Posted by benwaggoner

And note a lot of Dolby Vision devices don't support Profile 8.1, and most sources aren't in that either. Converting between DoVi versions requires a full tone remapping, beyond the abilities of something like Handbreak.

So far most streaming devices and Android TVs have no problem with YCbCr HDR10 + Profile 8.1 compatible RPU in the same stream, the Dolby engine interprets them correctly.
It's much more compatible than profile 7, at least

It's just a question of unsetting some flags and then the decoder has no problem. Converting profile 5 would be a different story.

[Nico8583]

Hi
I'm interested, my TV is a Samsung Q70R so not compatible with DoVi, only HDR10+. What is the result if I recode a DoVi stream to x265 DoVi stream ? It will play as a standard HDR10 stream or it will not be compatible ?
Thank you.

[benwaggoner]

Originally Posted by Nico8583

Hi
I'm interested, my TV is a Samsung Q70R so not compatible with DoVi, only HDR10+. What is the result if I recode a DoVi stream to x265 DoVi stream ? It will play as a standard HDR10 stream or it will not be compatible ?
Thank you.

If it is a Profile 8.x source, then the bitstream is in a "native" color volume and will work without the metadata, although perhaps with lower quality without the dynamic metadata.

If it's a non-backwards compatible base layer, like Profile 5, you'd need to do a full tone mapping conversion with specialized tools. That's a full format conversion, not even a straight reencode let alone a remux.

[Nico8583]

Thank you !
How can I know the DoVi profile version ? With MediaInfo ?
And how does it work with original Blu ray ? My TV will play it as an HDR / HDR10 stream ? I don't have any DoVi BD now so I can't try but I ask for the future.

[benwaggoner]

Originally Posted by Nico8583

Thank you !
How can I know the DoVi profile version ? With MediaInfo ?
And how does it work with original Blu ray ? My TV will play it as an HDR / HDR10 stream ? I don't have any DoVi BD now so I can't try but I ask for the future.

MediaInfo should tell you.

And I don't think any DoVi BD titles use 8.x.

[Nico8583]

Originally Posted by benwaggoner

MediaInfo should tell you.

And I don't think any DoVi BD titles use 8.x.

Thank you so DoVi BD use profile 5 ? Or 7 ?

[quietvoid]

Originally Posted by Nico8583

Thank you so DoVi BD use profile 5 ? Or 7 ?

Profile 7.

[Nico8583]

Originally Posted by quietvoid

Profile 7.

Thank you so if I want to convert an DoVi BD (profile 7) to x265 DoVi file I must use profile 5, 8.1 or 8.2 because x265 supports only these profiles ?
And I must convert profile 7 to profile 8.1 so I can keep HDR10 + DoVi metadata ?
Thank you.

[quietvoid]

Correct. However, you can only convert profile 7 to 8.1 with the existing tools. Since they share the same HDR10 base layer.
Profile 5 conversion is much more complex.

[Nico8583]

OK thank you I'll try it. There are DoVi BD with profile 5 or all are profile 7 ? There is no quality difference between profile 7 or 8.1 ? Thank you.

[quietvoid]

All Dolby Vision UHD BDs are profile 7.

Profile 7 FEL has the potential to be better, but in most cases (and current technology) it is not noticeably so.
It is also only fully compatible on UHD BD players.
Profile 7 MEL is equivalent to profile 8.1.

You can use google to find the differences between FEL and MEL.

[Blue_MiSfit]

Erm, Profile 7 supports an enhancement layer, but 8.1 does not (just metadata on top of the HDR10 base)

[quietvoid]

Originally Posted by Blue_MiSfit

Erm, Profile 7 supports an enhancement layer, but 8.1 does not (just metadata on top of the HDR10 base)

Profile 7 MEL has a useless enhancement layer, so it's pretty much the same metadata.

[Nico8583]

And there is no link between Dolby Vision metadata and HDR10+ metadata ? It's not possible to find a way to convert DoVi metadata informations to HDR10+ ? I don't know the structure of each file, perhaps it's stupid.