Posts by CptHenry

  • Feature Request: DRM/Framebuffer Access for Screenshot/Grabber Tools on Raspberry Pi 5 (LibreELEC 12 / VC6)

    chewitt

    Thanks a lot, I did.

    [Feature Request] Expose current scanout framebuffer for screenshot/grabber tools on Raspberry Pi 5 (VC6 DRM/KMS) · Issue #6860 · raspberrypi/linux
    Describe the bug Summary This is a feature request for Raspberry Pi 5 devices using the VC6 DRM/KMS driver. We are developing screenshot and grabbing tools…
    github.com


    I hope to make Hyperion work again on the Raspberry 5.

  • Feature Request: DRM/Framebuffer Access for Screenshot/Grabber Tools on Raspberry Pi 5 (LibreELEC 12 / VC6)

    Hello LibreELEC developers,

    I'd like to suggest a feature that could benefit many community projects, especially those related to Hyperion (Ambilight) and screenshot-based display analysis.

    Goal:

    Enable access to the current scanout framebuffer on Raspberry Pi 5 with VC6/KMS driver – for use in screenshot or grabber tools – by optionally providing:

    • a kernel module
    • a char device (/dev/scanout-export)
    • a DMA-Buf export point
    • or an alternative interface (e.g. DRM plane clone, gbm_bo_export, etc.)

    Background:

    Since the move to KMS + VC6 on Raspberry Pi 5, it is no longer possible to access the visible framebuffer using traditional means like:

    • drmModeGetResources()
    • drmModeGetPlane()
    • gbm_bo_map()

    Errors such as EOPNOTSUPP are returned for plane/resource queries, breaking:

    • Hyperion DRM grabbers (VC4 still worked)
    • DRM-based screenshot tools
    • Live color analysis (e.g. ambient lighting, automation)

    Why this matters:

    Hyperion and other tools rely on capturing the live screen content for Ambilight effects or HDMI-based automation.

    Under LibreELEC 12 (aarch64, VC6), this capture is currently not possible at all.

    ✅ Proposal:

    • Provide an optional kernel module or grabber interface
    • Make the current scanout framebuffer accessible through DMA-Buf export
    • Alternatively, expose a linear, readable framebuffer via a lightweight device (e.g. /dev/scanout-dma)

    I'm happy to help testing this or discussing viable implementation options.
    Even partial access or a Kodi-based workaround could unblock community projects.

    Thank you for considering –
    Greetings from the North,
    CptHenry