Motion Compensated Interpolation for Effective De-Interlacing in Consumer Electronics

1. AN EFFECTIVE DE-INTERACING TECHNIQUE USING MOTION COMPENSATED INTERPOLATION IEEE TRANSACTION ON Consumer Electronics, AUG. 2000 You-Young Jung, Byung-Tae Choi, Yung-Jun Park and Sung-Jea Ko 2005. 05. 03

2. < Abstract > • A new de-interlacing algorithm using motion compensated interpolation is suggested • First, motion estimation is performed between the same parity fields • Then the motion vector is refined in the interpolation field • For further improvement, a five point median filter with temporal emphasis is used to reduce the interpolation error caused by incorrect motion

3. < ⅠINTRODUCTION > • Current TV systems has visual artifacts such as an edge flicker, an interline flicker and line crawling • De-Interlacing which is a picture format conversion form interlaced to progressive picture has been widely used to reduce the those artifacts • HDTV systems support the progressive scan but camera and TV system still support the interlaced scan • Various de-interlacing techniques • fixed vertical-temporal filtering[2], edge-based line average[4]-[5], motion adaptive techniques[6]-[7]

4. < ⅠINTRODUCTION > • The basic concept of motion adaptive schemes is to select the appropriate interpolation method according to the motion of the image – spatial filtering in motion area and temporal filtering in static area • But, this approach is highly dependent on the accuracy of motion estimation • We propose a new de-interlacing scheme using the motion-compensated field interpolation and the field merging technique

5. <ⅡDE-INTERLACING TECHNIQUES> • The ELA-based technique is the most popular since it exhibit good performance with small computational load • The ELA algorithm uses the directional correlations between pixels to interpolate

6. ELA-based technique introduces flicker at motion area • One of solutions is motion compensation for inter-field processing • Before motion estimation, the previously de-interlaced field is inserted in the current missing field • Motion Estimation • Three-point median filter

7. Ⅲ PROPOSED MOTION COMPESATED DE-INTERACING • fn-1, fn and fn+1 denote the previous, current and next field, respectively

8. Ⅲ-A The Motion Compensated Field Interplation

9. Ⅲ-A The Motion Compensated Field Interplation • It is often observed that inconsistencies or non-smoothness in the estimated vector field decreases the interpolated picture quality • We present the proposed smoothing scheme: Let B and Ni, where i=1,2,…,8 denote the current block and the eight nearest neighboring blocks around B in the interpolated field

10. Ⅳ FURTHER IMPROVEMENTS • The performance of the MCFI is satisfactory if the motion vectors are accurate and reliable. However, when the estimated motion vector is incorrect, the interpolated picture quality can be degraded • In this case, the intra-field interpolation using spatial information might be more reliable • The proposed scheme uses a five-point median filter for intra and inter-field interpolation

11. Ⅴ EXPERIMENTAL RESULTS • For motion estimation, the block size is 16x8, search range for initial motion estimation is ±8, and the search range for refinement of the initial motion vector is ±2

12. Ⅴ EXPERIMENTAL RESULTS

13. Ⅴ EXPERIMENTAL RESULTS Performance of de-interlacing methods on Flower garden sequence