An enhanced estimation: motion and rotation estimation by FB80043

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									  An enhanced estimation:
motion and rotation estimation

         SHAN-HSIANG SHEN
                    Motivation

 Video encoding methods such as H.264 and MPEG
  use motion estimation to increase compression rate.
 Paste each blocks from some reference frame to
  create current frame.
 The more pixels can be matched, the more frame
  quality it can reach.
 Not only motion, but rotation.
          Motion estimation
Motion:

                       Rotation:
                 Rotation angles

 How many angle we will estimate depends on the
 block size.
                    Evaluation

 Evaluation program with Java Media Framework
 (JMF)


                      Motion and
     Video            Rotation
                                                  Video
     reader           estimation                  Writer


              Motion vector and angle
              (SAD for each frame will
              be available here for evaluation)
                                                 Evaluation

 Test video : 4.24 second-short video with 108 frames
  including some rotation object.
 Total SAD for each frame shows difference.
            18000000

            16000000

            14000000

            12000000                                                    Without rotation
                                                                        With rotation
            10000000
Total SAD




            8000000

            6000000
                                                                        Average SAD without rotation:
            4000000
                                                                                  3812728
            2000000                                                      Average SAD with rotation:
                  0                                                               3681778
                       0   20     40       60       80      100   120
            -2000000
                                sequence number of frames
                    Conclusion

 Motion and rotation estimation increase the number
  of pixel can be matched between current frame and
  reference frame.
 SAD is improved but not so much.
 The number of angle we estimation will be a trade-
  off between encoding time and performance.

								
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