New Adaptive Algorithms for GOP Size Control with Return Channel Suppression in Wyner-Ziv Video Coding

Pseudocode 1

Pseudocode of the recursive procedure R_PSNR_estimations used to estimate the rate and PSNR for all the frames in a GOP.

procedure R_PSNR_estimations(𝑖, len) {

 If len<2

   Return         // End of the recursive function calls

 Else

     𝑎=𝑖,𝑏=𝑖+len    //𝑎 and 𝑏 are the time indices

                  // of the frames used during the

                  // interpolation process.

   𝑑=⌊(𝑏−𝑎)/2⌋     // time interval from 𝑎 to the

                   // frame at mid distance

                   // between 𝑎 and 𝑏.

   SI_(𝑎+𝑑)=Interpolate(𝑎,𝑏)       // Perform average interpolation

                        // between frames at time

                        // indices 𝑎 and 𝑏.

   𝑄_(𝑎+𝑑)=QuantizeFrame(𝐹_(𝑎+𝑑))

   𝐑_(𝐚+𝐝)=EstimateBitrate(𝑄_(𝑎+𝑑))   // estimate the bitrate as

                         // explained in Section 2.

   𝐹^′_(𝑎+𝑑)=Reconstruct(𝑄_(𝑎+𝑑),SI_(𝑎+𝑑))      // reconstruct the

                          // quantized WZ frame

                          // given the estimated

                          // side information.

   𝐏𝐒𝐍𝐑_(𝐚+𝐝)=ComputePSNR(𝐹^′_(𝑎+𝑑),𝐹_(𝑎+𝑑))  // Compute the PSNR

                             // of the reconstructed

                             // frame.

   R_PSNR_estimations(𝑖, 𝑑);        // Recursive function call using

                           // the first half of the GOP.

    R_PSNR_estimations(𝑖+𝑑, len−𝑑)    // Recursive function call using

                           // the second half of the GOP.

 End If

}