Horizon OS NSDK Virtual Camera Publisher overview

• A drone or overhead camera that follows gameplay
• A selfie or avatar camera that faces the player
• A spectator camera for viewers in the same space
• A fixed cinematic shot of the environment

  Get started
• NSDK sample and integration guide⁠: step-by-step integration, build setup, and a working sample with EGL/GLES rendering.
• Unity-VirtualCameraPublisher on GitHub⁠: Unity package with C# integration.

1. Create manager — HzVirtualCameraManager_create
2. Configure — HzVirtualCameraConfiguration_init
3. Register camera — HzVirtualCamera_create
4. Wait for callbacks:
   • onStreamConfigured — A consumer opened the camera. Start rendering to the supplied ANativeWindow.
   • onProcessCaptureRequest(optional) — Generates a per-frame notification.
   • onStreamClosed — The consumer closed the camera. Stop rendering and release the window.
5. Destroy camera — HzVirtualCamera_destroy (unregisters the camera).
6. Destroy manager — HzVirtualCameraManager_destroy (releases resources).

1. Render frames to the window whose dimensions and format match the values passed in the callback.
2. Keep the window alive until onStreamClosed fires for the same streamId.
3. Call ANativeWindow_release⁠ after you stop rendering.

• onStreamConfigured: A consumer opened the camera. You receive the ANativeWindow*, dimensions, and format. Start rendering.
• onStreamClosed: The consumer closed the camera. Stop rendering and call ANativeWindow_release.

1. Create a manager with HzVirtualCameraManager_create.
2. Initialize the configuration with HzVirtualCameraConfiguration_init.
3. Declare at least one input stream configuration with HzVirtualCameraInputConfiguration_init (set width, height, format, maxFps).
4. Set the required callbacks: onStreamConfigured and onStreamClosed.
5. Register the camera with HzVirtualCamera_create.

• cx, cy = principal point. Use the image center: (width/2, height/2).
• fx, fy = focal length in pixels: fx = (width/2) / tan(hFOV/2), fy = (height/2) / tan(vFOV/2). Use fx == fy for square pixels (the common case).
• s = axis skew. Almost always 0.

// Lens facing: APP_DEFINED cameras must use EXTERNAL.
// FRONT and BACK are reserved for system cameras.
config.lensFacing = HZ_VIRTUAL_CAMERA_LENS_FACING_EXTERNAL;

// Sensor orientation in degrees (default: 0).
config.sensorOrientation = HZ_VIRTUAL_CAMERA_SENSOR_ORIENTATION_0;

// Intrinsic calibration for a 1920×1080 frame, ~88° hFOV, square pixels.
HzVirtualCameraLensIntrinsicCalibration calib = {
    .fx = 1000.0f, .fy = 1000.0f,    // focal length in pixels
    .cx = 960.0f,  .cy = 540.0f,     // principal point (image center)
    .s  = 0.0f                       // skew
};
config.intrinsicCalibration = &calib;

HzPose pose = {
    .orientation = {0.0f, 0.0f, 0.0f, 1.0f},  // identity quaternion
    .position    = {0.065f, 0.0f, 0.0f}       // 65 mm right of reference
};
config.lensPose      = &pose;
config.poseReference = HZ_VIRTUAL_CAMERA_LENS_POSE_REFERENCE_GYROSCOPE;

config.cameraThumbnailUri = "content://com.example.myapp/camera_thumbnail";

config.timestampSource =
    HZ_VIRTUAL_CAMERA_ACQUISITION_TIMESTAMP_SOURCE_SURFACE;

config.inputTimeoutMs       = 2000;  // wait up to 2 seconds (default: 1000)
config.inputTimeoutStrategy =
    HZ_VIRTUAL_CAMERA_INPUT_TIMEOUT_STRATEGY_REPEAT_FRAME;

config.perFrameCameraMetadataEnabled = true;
config.onProcessCaptureRequestWithMetadata = onCaptureRequestWithMetadata;

void onCaptureRequestWithMetadata(int32_t streamId,
                                  int32_t frameId,
                                  const uint8_t* metadata,
                                  size_t metadataSize,
                                  void* clientData) {
    if (metadata != NULL) {
        // Cast to camera_metadata* (libcamera_metadata format).
        // Valid only for the duration of this callback.
        const camera_metadata_t* camMeta =
            (const camera_metadata_t*)metadata;
        // Read consumer-requested settings (zoom, exposure, and so on).
    }
}

• com.meta.extra_metadata.camera_name: Human-readable name
• com.meta.extra_metadata.camera_thumbnail: Content URI for a thumbnail image (fetch with ContentResolver)
• com.meta.extra_metadata.position: Left or right position on the HMD front

HzVirtualCamera_destroy(camera);         // unregisters the camera
HzVirtualCameraManager_destroy(manager); // releases the manager

• Your app can register up to 3 cameras at the same time.
• The maximum supported frame rate is 60 fps.
• Testing over Meta Quest Link isn’t supported.