General information: Whitepaper | Beyond resolution – HDR, WCG and HFR
From the SSU report in the first post:
| Current Mode: 3840 x 2160 (32 bit) (120Hz) | Video files are rarely available with a refresh rate of 120 Hz. Actually only if you have recorded videos yourself this way. In all other cases this refresh rate is not necessary. This could affect automatic HDR detection. However, the latter primarily depends on the software player and the used DirectShow Rendering Filters. |
| HDR Support: Supported | System has recognized the suitability of the signal chain for HDR |
| Display Color Space: DXGI_COLOR_SPACE_RGB_FULL_G22_NONE_P709 | This is the color space defined in ITU-R BT.709 for HDTV (1080p/i). If HDR is enabled this should read "DXGI_COLOR_SPACE_RGB_FULL_G2084_NONE_P2020" ITU-R BT.2020 is the color space defined for Ultra-High-Definition Television (4K UHDTV) |
| Monitor Capabilities: HDR Supported (BT2020RGB BT2020YCC Eotf2084Supported ) | SMPTE ST 2084 is the industry's reference for High Dynamic Range Video Imaging. SMPTE = Society of Motion Picture and Television Engineers. The 2084 standard defines an electro-optical transfer function (EOTF) with a high luminance range capability. |
Dolby Vision typically includes additional (dynamic) metadata streams defined in SMPTE ST.2094-10. This is not supported on Windows Platforms for video playback as Dolby Vision is a largely closed licensed system from Dolby Laboratories for HDR videos and covers the creation, distribution and playback of content.
On Windows platforms only HDR10 with static metadata can be used for HDR video playback. Please check these settings. Set "Auto HDR" to ON as well:
Link Copied
Additionally here some information on how Dolby Vision is processed on Windows PC systems without Dolby licensing. From Dolby's specification:
Terms:
BL = Base Layer
EL = Enhancement Layer
N/A = not applicable
NALu = Network Abstraction Layer Unit
As already explained, there is the fallback level for profile 8 with output as HDR10 with corresponding static metadata that any TV and projector that complies with the HDR10 standard can handle.
MPC Video Renderer and VideoLAN's Libplacebo project also feature support for Dolby Vision profile 5 Base Layer and its IPTPQc2 color space which is converted to HDR10/PQ or SDR reading Dolby Vision data and reshaping it.
A video file with profile 5 can be found here. The properties of this file show:
Format: HEVC
Format/Info: High Efficiency Video Coding
Format profile: Main 10@L5.1@Main
HDR format: Dolby Vision, Version 1.0, dvhe.05.09, BL+RPU (Reference Picture Unit)
Codec ID: dvhe
Codec ID/Info: High Efficiency Video Coding with Dolby Vision
Duration: 1 min 38s
Bit rate: 28.2 Mb/s
Width: 3,840 pixels
Height: 2,160 pixels
Image aspect ratio: 16:9
Refresh rate mode: constant
Refresh rate: 59.940 (60000/1001) FPS
Color space: YUV
Chroma subsampling: 4:2:0 (Type 0)
Bit depth: 10 bits
Bits/(Pixels*Frame) : 0.057
Stream Size: 333 MiB (96%)
Default: Yes
Alternate group: 1
Color range: Full
Codec configuration box: hvcC+dvcC
If you use the MPC Video Renderer in MPC-BE playing this file, then this happens:
The Dolby Vision metadata is interpreted for output via ST.2084. Since the MaxCLL and MaxFALL information is regularly required for proper HDR10, this seems to be a compromise matter to me. LG stated 2019 their OLED's determination algorithm of PQ Luminance of content for static tone mapping as follows:
- Use ST.2086 Mastering Display Peak
- If MaxCLL is present AND lower than ST.2086 Mastering Display Peak, use MaxCLL
- If ST.2086 Mastering Display Peak and MaxCLL are both signalled as zero (as defined for unavailable), assume a peak luminance of 4000 nits
Dolby Vision is not inherently better than HDR10. When used correctly, both variants ensure optimal results if the hardware (TV or projector) allows it. Good display calibration often has much more influence on the image quality than the HDR technology itself. Only the true potential of Dolby Vision's dynamic metadata embedded in the video stream remains unused. That would allow televisions with reduced output in particular to add HDR without dark image content being lost or bright content being overloaded.
But if you have a TV that achieves the required HDR luminance of 1000 to 2000 nits, precise calibration of the white level is sufficient and you don't have to make any compromises even without full Dolby Vision signaling and hardware decoding.
Source: HDTVTest
