diff --git a/unix/x0vncserver/Geometry.cxx b/unix/x0vncserver/Geometry.cxx
index 728c113..94e2df6 100644
--- a/unix/x0vncserver/Geometry.cxx
+++ b/unix/x0vncserver/Geometry.cxx
@@ -60,16 +60,20 @@
             width(), height(), offsetLeft(), offsetTop());
 
   // Handle the VideoArea parameter, save the result in m_videoRect.
+  // Note that we log absolute coordinates but save relative ones.
   param = m_videoAreaParam.getData();
   bool videoAreaSpecified = (strlen(param) > 0);
   if (videoAreaSpecified) {
-    m_videoRect = parseString(param);
-    if (isVideoAreaSet()) {
+    Rect absVideoRect = parseString(param);
+    if (!absVideoRect.is_empty()) {
       vlog.info("Video area set to %dx%d+%d+%d",
-                m_videoRect.width(), m_videoRect.height(),
-                m_videoRect.tl.x, m_videoRect.tl.y);
+                absVideoRect.width(), absVideoRect.height(),
+                absVideoRect.tl.x, absVideoRect.tl.y);
+      Point base(-offsetLeft(), -offsetTop());
+      m_videoRect = absVideoRect.translate(base);
     } else {
       vlog.info("Video area was not set");
+      m_videoRect.clear();
     }
   }
   delete[] param;
diff --git a/unix/x0vncserver/Geometry.h b/unix/x0vncserver/Geometry.h
index 82da9c6..69ab687 100644
--- a/unix/x0vncserver/Geometry.h
+++ b/unix/x0vncserver/Geometry.h
@@ -33,13 +33,23 @@
 public:
   Geometry(int fullWidth, int fullHeight);
 
+  // Return coordinates and dimensions that specify a rectangular part
+  // of the desktop that would be shown to RFB clients. This
+  // information is extracted in the constructor from the "Geometry"
+  // parameter.
   int width() const { return m_rect.width(); }
   int height() const { return m_rect.height(); }
   int offsetLeft() const { return m_rect.tl.x; }
   int offsetTop() const { return m_rect.tl.y; }
+
+  // Return the same information as a Rect structure.
   const Rect& getRect() const { return m_rect; }
 
-  bool isVideoAreaSet() const { return !m_videoRect.is_empty(); }
+  // Return coordinates of the video rectangle if one was set with the
+  // "VideoArea" parameter. The coordinates are relative to the whole
+  // rectangle as returned by getRect(). In other words, the
+  // coordinate (0, 0) corresponds to the top left corner of the
+  // rectangle shown to RFB clients.
   const Rect& getVideoRect() const { return m_videoRect; }
 
 protected: