Ai-mei Huang And Truong Nguyen IEEE, WORLD OF WIRELESS, MOBILE AND MULTIMEDIA NETWORKS. (WOWMOM), 2008 IEEE, WORLD OF WIRELESS, MOBILE AND MULTIMEDIA NETWORKS. (WOWMOM), 2008 Motion vector processing using bidirectional frame difference in motion compensated frame interpolation

Motion compensated frame interpolation(1/3)

Motion compensated frame interpolation(2/3) A example

Motion compensated frame interpolation(3/3) Although the MV is measured reliably in [4] Still have some potential issues In Fig 2 and 3, the moving object is composed of four blocks, {B 1,B 2,B 3,B 4 } Fig. 3 shows that even MVs are correctly estimated, the moving object still cannot be reconstructed successfully. the simplest way to reduce these visual artifacts is to find the best matches bi-directionally by minimizing the difference between bidirectional predictions. [4]A.-M. Huang and T. Nguyen. Motion vector processing based on residual energy information for motion compensated frame interpolation. in Proc. ICIP’06, pages 2721–2724, 2006.

Bidirectional motion vector processing for MCFI(1/2) Use bidirectional MV processing for the received MVF in the current decoder frame f t+1. we select the best MV from a set of MV candidates V b *, is selected based on the minimum difference between forward and backward predictions.

(2/2) Eliminate the ghost artifacts due to unmatched bidirectional predictions Computation is greatly reduced Use the integer-pixel frame interpolation affect MV precision. modify eq. (4) to allow MVs have small deviation from -1 to 1.

SIMULATIONS Compare our method with direct MCFI, and vector median filter (VMF). Test sequence QVGA size: FORMULA 1, TABLE, and STEFAN CIF size: FOREMAN, FORMULA 1, FAST FOOD, WALK, and SILENT Encode using H.264, avg. bitrate: 384kbps even frames are skipped.

Adopt structure similarity (SSIM) index for quality assessment. luminance contrast Structure

Performance

CONCLUSIONS The motion vector reliability is analyzed and classified. we examine how the MV precision affect the quality of the interpolated frame in the bidirectional MCFI scheme. we propose a bidirectional MV processing method by selecting the best MV from neighboring MVs