Expose frame of reference uid via property

Author: hackermd

src/viewer.js

@@ -1984,6 +1984,15 @@ class VolumeImageViewer {
     return this[_pyramid].pixelSpacings.length
   }
 
+  /**
+   * Frame of Reference UID.
+   *
+   * @type string
+   */
+  get frameOfReferenceUID () {
+    return this[_pyramid].metadata[0].FrameOfReferenceUID
+  }
+
   /**
    * Get the pixel spacing at a given zoom level.
    *
@@ -4452,6 +4461,15 @@ class _NonVolumeImageViewer {
     return this[_metadata]
   }
 
+  /**
+   * Frame of Reference UID.
+   *
+   * @type string
+   */
+  get frameOfReferenceUID () {
+    return this[_metadata].FrameOfReferenceUID
+  }
+
   /**
    * Resize the viewer to fit the viewport.
    *