A i - m e i H u a n g A n d Tr u o n g N g u y e n 

I E E E , W O R L D O F W I R E L E S S , M O B I L E A N D M U LT I M E D I A N ET W O R K S . (

W O W M O M)   , 2 0 0 8 

Motion vector processing using bidirectional frame difference in

motioncompensated 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, {B1,B2,B3,B4}• 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 basedon residual energy information for motion compensated frameinterpolation. in Proc. ICIP’06, pages 2721–2724, 2006.

Bidirectional motion vector processing forMCFI(1/2)

• Use bidirectional MV processing for the received MVF in the current decoder frame ft+1.• we select the best MV from a set of MV candidates

• Vb* , 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 qualityassessment.

• 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