+----------------+             
                   |  Calculate     | <---- RTCP report
                   | Reference Rate | 
                   -----------------+
                           | r_ref
              +------------+-------------+
              |                          |
             \|/                        \|/
      +-----------------+           +---------------+
      | Calculate Video |           |   Calculate   |
      |  Target Rate    |           | Sending Rate  |
      +-----------------+           +---------------+
          |        /|\                 /|\      |   
    r_vin |         |                   |       |
         \|/        +-------------------+       |       
      +----------+          | buffer_len        |  r_send
      |  Video   | r_vout  -----------+        \|/
      |  Encoder |-------->   |||||||||=================>  
      +----------+         -----------+    RTP packets     
      Rate-Shaping Buffer