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Adaptive Fast Block-Matching Algorithm by Switching Search Patterns for Sequences With Wide-Range Motion Content. 韋弘 2010-07-05. Introduction. reference frame current frame.
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Adaptive Fast Block-Matching Algorithm by Switching Search Patterns for Sequences With Wide-Range Motion Content 韋弘 2010-07-05
Introduction reference frame current frame motion vector residual
Introduction • remove the temporal redundancy • switch FBMA among the motion contents • A-TDB algorithm based on predicted profit list
Outline • Basic Methods • Predicted Profit List • A-TDB Algorithm • Results • References
Outline • Basic Methods • Predicted Profit List • A-TDB Algorithm • Results • References
Fast Block-Matching Algorithm • three-step search (TSS) • new three-step search (NTSS) • block-based gradient descent search (BBGDS) • diamond search (DS) • four-step search (FSS)
Outline • Basic Methods • Predicted Profit List • A-TDB Algorithm • Results • References
Predicted Profit List • Initial:MSE(profit) at (0,0) • a sorted list of blocks in descending order of profit
Characteristics(1/4) • the distribution of the profits is not uniform
Characteristics(2/4) • the blocks usually include several various motion contents
Characteristics(3/4) • the MVs of the neighboring blocks are strongly correlated
Characteristics(4/4) • the MV is very likely to be zero near the end
Outline • Basic Methods • Predicted Profit List • A-TDB Algorithm • Results • References
Initialization Phase • the other objective • determine theinitial rate of motion in the adaptive zone (based on MVs) • MV(length) > (¼)x(search range) => rapid • MV(length) 1 => slow • if successive Tiblocks have rapid (moderate or slow) => change to adaptive phase
Cleanup Phase • When does A-TDB change to the cleanup phase? • predicted profits of the blocks < threshold (predefined) • the MVs found are consecutive zero (Tc) • What does the cleanup phase do? • skip the remaining blocks in the profit list • A-TDB stops
the effect of Ti • the value of Ti is negligible
the effect of Ta • 2, 3, and 4 are good choices for Ta
Outline • Basic Methods • Predicted Profit List • A-TDB Algorithm • Results • References
Outline • Basic Methods • Predicted Profit List • A-TDB Algorithm • Results • References
References • [1]S.-Y. Huang, C.-Y. Cho, and J.-S. Wang, “Adaptive fast block-matching algorithm by switching search patterns for sequences with wide-range motion content”, IEEE Trans. Circuits and Systems for Video Technology , vol. 15, no. 11, p.p.1373-1384, Nov. 2005. • [2] L. K. Liu and E. Peig, “A block-based gradient descent search algorithm for block motion estimation in video coding,” IEEE Trans. Circuits Syst. Video Technol., vol. 6, no. 8, pp. 419–423, Aug. 1996. • [3] S. Zhu and K.-K. Ma, “A new diamond search algorithm for fast block matching motion estimation,” IEEE Trans. Image Process., vol. 9, no. 2, pp. 287–290, Feb. 2000. • [4] A. Andersson, T. Hagerup, S. Nilsson, and R. Raman, “Sorting in linear time,” J. Comput. Syst. Sci., vol. 57, pp. 74–93, 1998.