Intel Arc A310: QSV works, but OpenCL HDR tone mapping fails with Small BAR in official Emby Docker image

[Kwin 3]

Hello,

  I am having an issue with hardware HDR-to-SDR tone mapping in Emby Server on Linux.

  Hardware:

•   GPU: Intel Arc A310 (DG2)
•   Host platform: Intel Z170
•   BAR2 size: 1 GB maximum on this platform
•   Resizable BAR cannot be increased to 4 GB on this system
•   GPU device: /dev/dri/renderD129

  Software:

•   Ubuntu
•   Kernel: 7.0.0-30-generic
•   Emby Server: 4.9.5.0
•   Official Docker image: emby/embyserver:latest
•   Firefox client on Windows

  Input:

•   HEVC Main 10
•   1920x800
•   Dolby Vision Profile 8.1 / HDR10-compatible
•   EAC3 5.1 audio

  The source plays correctly when hardware tone mapping is disabled. QSV decoding and encoding also work correctly.

  However, when Emby selects QuickSync ExtraT/OpenCL tone mapping, FFmpeg fails during QSV-to-OpenCL mapping:

•       WARNING: Small BAR detected for device 0000:03:00.0
•       Failed to get number of OpenCL platforms: -1001
•       Failed to create derived device context
•       Error while processing the decoded data
•       Conversion failed

  The selected processing pipeline is:

•       HEVC_QSV
•       hwmap -> OpenCL
•       tonemap_opencl
•       hwmap -> QSV
•       HEVC_QSV

  After this failure, Emby falls back to software decoding and x265 encoding. Performance drops to approximately 0.4x
  realtime, even though the Arc A310 handles QSV transcoding easily.

  When tone mapping is disabled, the same GPU performs the transcode at several times realtime.

  I also tested a newer Intel OpenCL runtime (NEO 26.31) in a separate container. OpenCL platform detection works there
  despite the 1 GB BAR, but the QSV/OpenCL media-sharing path still fails.

  Could the official Emby Docker image be updated to include a newer Intel Graphics Compute Runtime and a compatible FFmpeg/
  QSV OpenCL media-sharing configuration?

  Important clarification:

•   Increasing the BAR to 4 GB is not possible on this motherboard.
•   The 1 GB BAR is therefore expected and must be supported.
•   QSV decode/encode itself works; only the OpenCL tone-mapping path fails.

  As a workaround I currently have hardware tone mapping disabled, which makes playback work but removes HDR-to-SDR
  conversion.

  I can provide the complete Emby and FFmpeg logs if needed.

[Q-Droid 1048]

HW tone mapping is broken in the stable branch. Feel free to try the beta release though you might want to search the forum to find which ones actually work. Regressions happen...

 

 

[Kwin 3]

Thanks Q-Droid! Rolling-back to 4.9.1.90 fixed the issue. Your golden tip is greatly appreciated!