Dolby Vision Profile 7 support (.ts/.mkv files)

Sadly that isn’t the whole story.

Plex have been triggering Dolby Vision on the Apple TV for a year or so now and that just entails forcing the Apple TV into DV mode and playing HDR. It will happily do it with Profile 7 also.

Infuse with Profile 8 I think is currently (and I know possibilities of more compatibility is being worked on) is doing the same to accommodate one of the Profile 8 levels (things shot in DV on the iPhone which really will be DV).

I may be wrong on this but in Profile 5 (real DV on the ATV4K) video scrubbing thumbnails are black and white. My rule of thumb since then is if the video scrubbing is in colour it’s not really DV.

I would love some clarification on this but either way it’s not the end of the world.
I just have to get away from the awful Nvidia Shield.

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This is mostly true for now. If the thumbnails are black and white this means the videos is DV-only with no fallback layer. For videos with an HDR fallback layer Infuse will be able to use that for video thumbnails.

Regardless, support for displaying proper color thumbnails for all DV videos is something which will be available in an upcoming version.

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DV P8.4 means compatibility ID 4, which uses HLG. That’s what the ATV 4K 2021 supports because that’s what an iPhone 12/13 uses when it shoots video in DV. HLG is designed for those sorts of scenarios where HDR content needs to be generated in real-time. Same reason HLG is used in live TV broadcasts, like for sports.

So at this point Infuse supports P8.4 but not P8.1.

DV P8.1 means compat ID 1, which uses HDR10, same as DV P7. Hence people want to convert P7 BL+EL+RPU to P8.1 BL+RPU, dropping the EL.

When playing back P8.1 files (dvhe.08.06) in Infuse that have been converted to BL+RPU from a UHD BD in P7 with BL+EL+RPU (dvhe.07.06), it is triggering DV on the display, but the colors aren’t correct.

The colors aren’t as off as they are when using the DV P5 with IPT color, but they appear dull and don’t match HDR10 versions of the same video played back in Infuse, or DV P7 played back from a UHD BD player.

So this is where, if the RPU from DV 8.1 videos can be interpreted correctly, or converted to P5, or reinterpreted on the fly as P5 (except with HDR10 and BT.2020 color) we could have an interesting path towards playing back files in Infuse that have gone from UHD BD P7 BL+EL+RPU → P8.1 BL+RPU → P5 BL+RPU.

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What is the advantage of playing something back in Dolby vision over HDR if we are dropping the EL during conversion process?

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The EL is really only useful if it contains information.

In the case of DV P7 Full Enhancement Layer (FEL), the EL contains both (1) a 10-bit video stream that is combined with the 10-bit BL video stream to arrive at the full 12-bit video stream for playback, and (2) the RPU, the dynamic metadata that provides HDR levels per scene.

So when the input to the DV encoding process is a 12-bit video master, P7 FEL is currently the only way to get a 12-bit video stream out on the other end for playback. P7 FEL has the highest quality potential of any DV profiles.

DV P7 also supports a Minimal Enhancement Layer (MEL). In that case, the EL carries a null video stream with no video data at all and the RPU. So MEL is basically a backwards-compatible way to transport an RPU when the playback device expects an EL separate from the BL.

But it provides no picture-quality advantage over other DV profiles that don’t require an EL, where devices supporting those profiles are capable of processing the RPU embedded alongside the BL stream.

P5 & P8 both use just BL+RPU, no EL.

So, the point in dropping the EL is to get from a playback format intended for UHD BD (BL+EL+RPU) to a playback format intended for streaming devices (BL+RPU) by dropping the EL video track but not the dynamic RPU data.

Studios are making their own choices with each UHD BD release.

Some are MEL, in which case you can losslessly convert from P7 BL+MEL+RPU to P8.1 BL+EPU without losing any data actually used during playback — you’re just changing where the RPU is located in the overall muxed stream. So if you’re dropping the EL when processing a release using an MEL, you aren’t losing any quality.

Some are FEL, in which case you would lose the full 12-bit video stream on playback when converting P7 BL+FEL+RPU to P8.1 BL+RPU. When you lose those 2 bits of color, you might be able to see more instances of color banding on your TV, but there are also arguments that the extra 2-bits of color aren’t really useful today — including that you basically just get extra headroom for more brightness, which today’s consumer displays can’t display, anyway. Meanwhile, you get the advantage that you can play back on a streamer instead of the hassle of a UHD BD player.

So you drop the EL to gain convenience and a superior playback experience, and you might lose a little quality or nothing at all.

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Thanks for the detailed info! I knew some of it but finding one spot that also all the relevant info in one page as opposed to 50 is very helpful.

So ideally we could convert all profile 7 mkv to profile 8 mkv for playback in infuse. Only missing out on FEL which may or may not provide enhancements since everyone’s panels are 10-bit atm.

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Yeah that’s a fantastic post that makes it far simpler to get my head around than everything I have read before.

Unlike @munpip214 i knew hardly any of it.

I have just looked at the Profile 8 Hybrid Remuxes that are out there in download land and they are all BL+RPU with HDR10 fallback.

So going off something that (from my vague memory) James mentioned previously regarding fallback tracks being a problem, where would that leave us?

I’m not up on the terminology to know what the community calls a “hybrid” remux, but I’m guessing that means they either took a UHD BD released in DV and converted the P7 BL+EL+RPU to P8.1 BL+RPU, or they took a UHD BD released in HDR10 and combined it with the RPU converted to P8.1 format from a P5 BL+RPU video released on a streaming service.

So it’s a full UHD BD remux, except with DV added to an HDR10 release or converted from P7 to P8.1.

Regardless, if you have P8 with HDR10 fallback, that means you have a P8.1 stream, which uses an HDR10 BL + the DV RPU data. So if a playback device can’t support DV it just uses the HDR10 BL — that’s the fallback.

Right now, a DV P8.1 file will play back in Infuse 7.3.1 and trigger DV (so doesn’t fall back), but the colors are inaccurate (in a different way than P5 files display). So you can watch the file, but the colors will be more dull than had you just watched the BL in HDR10 without DV triggered. Colors basically just look very desaturated. That may be the problem with fallback that James was identifying, I’m not sure.

I think the current idea is to try converting the P7 or P8 RPU to P5, because that is explicitly what the ATV 4K supports. The P5 spec states that the color representation should use Dolby’s proprietary IPT format, so it isn’t designed to use HDR10 (which specifies BT.2020 color) but apparently there’s evidence it would work, in that DV versions of Apple’s ATV screensaver videos are actually HDR10 video streams with DV P5 RPU metadata.

So that means our best bets are either A) Firecore gets P8.1 working properly, or B) the community creates a tool to convert P7 or P8 RPU metadata to P5. Right now, dovi_tool will convert P5 to P8 but not vice versa, so it seems possible.

I haven’t tested it myself, but my understanding is that Infuse 7.3.1 also supports DV P8.4, which means it has a BL video stream in HLG format instead of HDR10. If you’re using the ATV 4K 2021 model, that should support P8.4 with HLG just fine. The ATV 4K 2017 model may also support HLG, but it isn’t explicitly stated in the tech specs.

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This approach appears to become more common and the motives are pretty obvious, it’s quite a waste of storage and traffic to keep separate HDR10 and DV P5 files. Unfortunately that’s bad news for us Infuse users.

This makes the situation even worse: Now there’s a chance that you will only find one version that won’t work at all, instead of two separate ones that would. It would be great if Infuse could at least fall back to HDR10 properly.

sadly yes ,all I can see coming now is DV+hdr10 so profile 8,and it makes a lot of sense

Ik.apple doesn’t support it ,but would it eve be possible to make it work by reverse engineering ?

Technically, ATV DOES support DV dynamic metadata + HDR10 base layer, just in a non-standard way. Take a look at the ATV aerial screensavers for example. They’re marked as DV profile 5 but have an HDR10 base layer.

Добрый день !
Я новенький и только постигаю.
Скажите пожалуйста, почему у меня так получается?
Видео снятое на iPhone 12 Pro в формате 4K HDR - DV, в вертикальном виде, потом при просмотре в infuse в верх ногами (( на Plex или VLC все ок
Видео более старое в формате 4K HDR - все нормально?

Good afternoon!
I’m new and I’m just learning.
Please tell me why I do it this way?
Video shot on iPhone 12 Pro in 4K HD - DV format, in vertical form, then when viewed in infuse upside down (( on Plex or VLC everything is ok
The video is older in 4K HDR format - is everything OK?

That is, ofc, very annoying and Firecore should definitely fix it if possible.

But, when in a bind, if you use dovi_tool to convert the RPU to be MEL compatible (P7), or demux the RPU to remove it altogether, and then remux the BL (and optionally the EL+RPU in P7) with the other tracks, you can produce a file that will work with Infuse in HDR10.

To see if I could replicate what the ATV screensavers are doing, I tried extracting the RPU from a DV P5 track with an IPT BL and injected that RPU into an HDR10 BL.

So I had an HDR10 BL + P5 RPU, which I remuxed into MKV, and Infuse played it back as HDR10; it didn’t trigger DV.

I’m going to try remuxing into an MP4 container and will test that next. I don’t know if others have tested this, but it doesn’t seem this trick works today.

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Добрый день !

Спасибо, буду с нетерпением ждать решения проблемы и что бы Infuse смог проигрывать мое домашнее видео без проблем

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It needs very specific fields in the metadata to trigger DV. I’ve heard some people have success using a modified version of TSMuxer to make .ts/.m2ts files with a profile 5 marker. If you feel handy, you can try download the TSMuxer source from github and doing the mod yourself.