Test ipu6 webcam on NixOS

test-webcam.sh

#! /usr/bin/env nix-shell
#! nix-shell -i bash -p linuxPackages_latest.v4l2loopback gst_all_1.gstreamer

function usage() {
  echo "Usage: $0 <platform name> [--webcam]"
  echo "Supported platforms are: ipu6, ipu6ep, ipu6epmtl"
  exit
}

PLATFORM="$1"

case "${PLATFORM}" in
  ipu6 | ipu6ep | ipu6epmtl) ;;
  *)
    echo "Invalid platform provided"
    usage
    ;;
esac

if [[ "$2" == "--webcam" ]]; then
  WEBCAM_MODE=1
elif [[ -n "$2" ]]; then
  usage
else
  WEBCAM_MODE=0
fi

if [[ "$PLATFORM" == "ipu6" ]]; then
  FORMAT="YUY2"
else
  FORMAT="NV12"
fi

if [[ $WEBCAM_MODE == 0 ]]; then
  case "${XDG_SESSION_TYPE}" in
    wayland)
      SINK=waylandsink
      ;;
    x11)
      SINK=ximagesink
      ;;
    *)
      echo "Couldn't detect session type"
      echo "Please set XDG_SESSION_TYPE to x11 or wayland"
      exit
      ;;
  esac
else
  DEVICE=$(sudo v4l2loopback-ctl add -x 1 -n 'Test webcam')
  SINK="v4l2sink device=$DEVICE"
fi

export NIXPKGS_ALLOW_UNFREE=1
export GST_PLUGIN_PATH=$(nix eval --raw --impure --expr "let pkgs = import <nixpkgs> {}; in with pkgs; with gst_all_1; lib.makeSearchPathOutput \"lib\" \"lib/gstreamer-1.0\" [ gst-plugins-bad gst-plugins-base gst-plugins-good gstreamer.out icamerasrc-$PLATFORM ]")

sudo -E gst-launch-1.0 icamerasrc ! video/x-raw,format=$FORMAT,width=1280,height=720 ! videoconvert ! $SINK &>/dev/null

if [[ $WEBCAM_MODE == 1 ]]; then
  sudo v4l2loopback-ctl delete "$DEVICE"

  if [[ -c "$DEVICE" ]]; then
    echo "Failed to delete the loopback camera (likely because it was still in use)"
    echo "Run 'sudo v4l2loopback-ctl delete $DEVICE' after it is no longer in use (or just reboot)"
  fi
fi