OSMC implements display-led (TV-led) Dolby Vision with support for CMv2.9 and CMv4.0. Currently, the status of this implementation is as follows:

Profile Expected Behaviour
4 Plays SDR base only, even to a DV compatible display
5 Plays well on DV displays as well as HDR displays as it did previously, but now passing through display management metadata to DV displays.
7 Plays well with display management metadata passed on to DV displays. Dual tracks are merged to a single track. If playing FEL, this is discarded with BL + RPU used only.
8.1 Plays well with display management metadata passed on to DV displays.
8.4 Plays the HLG base layer only even to a DV display

Frequently asked questions

What is Dolby Vision?

Dolby Vision (DV) is a technology for High Dynamic Resolution (HDR) video. Its objective is to:

  • re-create (using the ‘composer’) as close as possible the 12-bit video that the colourist optimised in the editing studio
  • tonemap the result to suit the user’s display (using the ‘display mapper’). The instructions for this (metadata) are generated by algorithm, but with adjustments the colourist may make while monitoring on a typical consumer TV.

The main monitor used in the editing suite will have a very high dynamic range with maximum peak luminance of 1000 nits or more. Domestic TVs, especially cheaper ones and OLEDs will not be that bright so the signal needs to be tonemapped to avoid losing detail in the highlights while maintaining contrast in the mid-tones. Note also that no displays can achieve their peak luminance over the whole screen at once. Ideally, the tonecurve is different for each scene and this is what DV does using dynamic metadata.

What is a Dolby Vision Profile?

Blu-rays with DV use ‘Profile 7’. The video has a ‘base layer’, compatible with HDR10 and an ‘enhancement layer’ which is merged with the base layer in the composer. The enhancement layer contains the instructions for the merge and the dynamic metadata for the display mapper.

Profile 7 video is what you get by backing up your DV Blu-rays to a hard disc (usually MKV format).

Streaming services may use ‘Profile 5’. This is a system optimised for efficient streaming. There is only one layer which is a proprietary format in an ‘IPT-PQ-c2’ colourspace. This needs to be converted to a format that can be sent via HDMI to the display. The stream includes dynamic metadata for the conversion and the display mapper. Software is available to capture Profile 5 streams and store them as files.

‘Profile 8’ is a single-layer system in which the layer is compatible with an existing video format - HDR10 (8.1), HLG (8.4) or SDR (8.2). Profile 8.1 files have often been converted from Profile 7. iPhones can record in profile 8.4.

What do TV-led and player-led mean?

With DV, the composer part is always in the player. The display mapper may be in the player (player-led mode) or in the display (display-led or TV-led mode). Players supporting player-led can be tricked into converting DV to ‘Low Latency DV’ (similar to HDR10) and sending that to a non-DV display. TV-led should be the preferred method for users with a DV display since the display manufacturer should know best how to tailor the video for his hardware.

What are FEL and MEL?

In Profile 7 video, the enhancement layer may be ‘full’ (FEL) or ‘minimum’ (MEL). FEL includes a video stream which modifies every pixel of the base layer. MEL is equivalent to Profile 8.1. FEL requires sophisticated decoder hardware and support for it seems to have been dropped in newer kernels and Android versions. Software is available which can merge a FEL into the base layer to produce a Profile 8.1 video.

How can I play Dolby Vision with OSMC?

To play Dolby Vision in the best possible quality you need a TV/display that supports Dolby Vision Standard Mode. With other displays, the quality can only be as good as HDR10. Early Sonys and some Panasonics offer only Low Latency Mode which we do not support.

Vero V devices will pass through Profile 7 and 8.1 video together with the display mapper metadata for a DV display to operate in TV-led mode. Non-DV displays will be sent the base layer only - as-is for an HDR display or tonemapped for an SDR display.

Vero V devices will apply the shaping metadata to a Profile 5 stream. The result will be sent to a DV display with the display mapper metadata, or to non-DV displays as HDR10 or (tonemapped) SDR as appropriate.

OSMC on Vero 4K, Vero 4k + and Raspberry Pi does not support Dolby Vision.

What about HDR10+? What support is there for my Samsung?

Some titles are available with both HDR10+ and DV metadata. These will play as DV on a DV display, HDR10+ on a TV that supports HDR10+ but not DV (Samsung) and HDR10/SDR otherwise.

We might be able to convert DV to HDR10+ in the future. But the metadata formats are very different so it’s unclear how good that conversion can be.