Figure 8.3 - Remote recognition, local tracking & registration

According to the MAR component classification scheme in Clause 7, this system class has the following characteristics:

• 
  Pure sensors – visual
  
• 
  Real world capturer – visual, 2D video
  
• 
  Recognizer – image patch, recognition event, remote
  
• 
  Tracker – image patch , spatial event, local
  
• 
  Space mapper - spatial
  
• 
  Event mapper - visual
  
• 
  Execution engine – local, 2D + t
  
• 
  Renderer - visual
  
• 
  Visual display – 2D mono
  

The Device sends a video stream (from a local camera capture, a local video track or a remote video resource) to a Processing Server that is analysing the data and detects one or several target resources that are stored in its local (or remote) database. Additionally, the Processing Server does the composition and rendering of the video frames, and sends back to the device the composed (augmented) video stream. The content specified in the Information viewpoint is:

• 
  URL to the video stream (a local camera, a local video track or a remote video resource).
  
• 
  URL to the Processing Servers.
  
• 
  Optional: a 2d region (in the video frame) to be considered in the recognition process and the number of frames per second expected from the processing server.
  

In addition, a communication protocol has to be implemented between the MAR Execution Engine and the Processing Server.