視頻播放加速

NixOS 中的視頻播放加速通常是通過向 hardware.graphics.extraPackages 添加相關包來完成的。

安裝

Intel

❄︎ /etc/nixos/configuration.nix

{
  hardware.graphics = {
    enable = true;
    extraPackages = with pkgs; [
      intel-media-driver # For Broadwell (2014) or newer processors. LIBVA_DRIVER_NAME=iHD
      intel-vaapi-driver # For older processors. LIBVA_DRIVER_NAME=i965
    ];
  };
  environment.sessionVariables = { LIBVA_DRIVER_NAME = "iHD"; }; # Optionally, set the environment variable
}

注意，intel-vaapi-driver 在較新的 Skylake (2015) 處理器上對於瀏覽器（基於 gecko/chromium）仍然表現更好。^[1]

對於 32 位支持，請使用 hardware.graphics.extraPackages32:

❄︎ /etc/nixos/configuration.nix

{
  hardware.graphics.extraPackages32 = with pkgs.pkgsi686Linux; [ intel-vaapi-driver ];
}

AMD

AMD 相關硬體（至少對於 Ryzen 5 iGPU 系列）支持開箱即用：

❄︎ /etc/nixos/configuration.nix

{
  hardware.graphics.enable = true;
}

NVIDIA

NVIDIA do not officially support accelerated video playback on Linux. A third-party implementation exists, but does not support Chrome^[2], and has significant limitations compared to the other implementations^[3].

擁有獨立 iGPU 的 NVIDIA 用戶通常應該更喜歡使用他們的 iGPU 來實現此目的，因此請參考上面的 Intel 和 AMD 部分。

Users with only an NVIDIA GPU can attempt to use the third party implementation; the package is added to hardware.graphics.extraPackages by default, but it requires some additional setup to be useful^[4]:

❄︎ /etc/nixos/configuration.nix

{ config, lib, ...}: {
  environment.variables.LIBVA_DRIVER_NAME = "nvidia"

  # If used with Firefox
  environment.variables.MOZ_DISABLE_RDD_SANDBOX = "1";

  programs.firefox.preferences = let
    ffVersion = config.programs.firefox.package.version;
  in {
    "media.ffmpeg.vaapi.enabled" = lib.versionOlder ffVersion "137.0.0";
    "media.hardware-video-decoding.force-enabled" = lib.versionAtLeast ffVersion "137.0.0";
    "media.rdd-ffmpeg.enabled" = lib.versionOlder ffVersion "97.0.0";

    "gfx.x11-egl.force-enabled" = true;
    "widget.dmabuf.force-enabled" = true;

    # Set this to true if your GPU supports AV1.
    #
    # This can be determined by reading the output of the
    # `vainfo` command, after the driver is enabled with
    # the environment variable.
    "media.av1.enabled" = false;
  };
}