Electrical Engineering Department of National Cheng Kung University Smart Media & Intelligent Living Excellence Lab. 1 2012/08/14 指指指指 指指指指指 : 指指指 指指指 : 指指 指指 DEMO DEMO line segment line segment 指 指 GPU GPU 指指 指指
Jan 25, 2016
Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab. 1
2012/08/14指導教授:詹寶珠教授
報告者:陳正旻
期末期末 DEMO DEMO line segmentline segment 的的 GPUGPU 實現實現
Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab. 2
OutlineOutline
演算法流程介紹 ( 附實作結果 )
時間比較和加速倍數實作影片總結
Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
Flow chartFlow chart
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
AlgorithmAlgorithm
Line segment construction
Two rules• Color difference :
•
• Spatial distance :
•
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
(TIME)Line segment construction(TIME)Line segment construction
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
Flow chartFlow chart
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
AlgorithmAlgorithm
Initial Disparity Computation
Matching cost :
• CAD :
• CCENSUS : Hamming distance of the two strings that stand for p and pd
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String
R. Zabih and J. Woodfill, “Non-parametric local transforms for computing visual correspondence,” in Proc. ECCV, 1994, pp. 151–158.
d=1Left Right
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
(TIME)Initial Disparity Computation(TIME)Initial Disparity Computation& Matching cost& Matching cost
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
AlgorithmAlgorithm
Cost aggregation
Winner-take-all
9d=1
Left Right
Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
(TIME)Cost aggregation(TIME)Cost aggregation& Winner-take-all& Winner-take-all
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
初步結果初步結果
左圖的 Depth 右圖的 Depth
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
Flow chartFlow chart
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
AlgorithmAlgorithm
Seed Pixel Detection
Two rules
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
(TIME)Seed Pixel Detection(TIME)Seed Pixel Detection
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
Flow chartFlow chart
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
AlgorithmAlgorithm
Scanline Propagation
• Aa , if p is in occluded regions.
• d
• Ss , if p is near depth discontinuities.
• a
• is replaced by the linearly interpolated results of and in all other conditions.
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
(TIME)Scanline Propagation(TIME)Scanline Propagation
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
Scanline PropagationScanline Propagation 之後的結果之後的結果
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
Flow chartFlow chart
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
AlgorithmAlgorithm
Disparity Refinement• Vertical voting : We collect 𝑁 disparity votes in a vertical
line segment that starts at pixel and ends at pixel
,if the color difference is smaller than the threshold value 𝜏 , the votes on disparity increase by 1.
• c
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
(TIME)Vertical voting(TIME)Vertical voting
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
Vertical votingVertical voting 之後的結果之後的結果
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
再加入再加入 BilateralFilterBilateralFilter 之後的最終結果之後的最終結果
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
GPU 運算時間
CPU 運算時間
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
時間比較和加速倍數時間比較和加速倍數LineSegment
漢明距離 單點 cost 總 cost
CPU 0.114000 (S) 0.481999 0.973999 0.352999
GPU 0.002498 (S) 0.004868 0.091873 0.016956
加速 約 45 ( 倍 ) 約 99 ( 倍 ) 約 11 ( 倍 ) 約 21 ( 倍 )
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Seedpixel
ScanLine
Verticalvoting
DBF GPU 總時間
0.020000 0.017000 0.098000 2.059997
0.000033 0.000239 0.002314 0.002 0.120781
約 606 ( 倍 ) 約 71 ( 倍 ) 約 42 ( 倍 ) 約 18 ( 倍 )
Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
實作影片實作影片
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Electrical Engineering Department of National Cheng Kung University
Smart Media & Intelligent Living Excellence Lab.
總結總結
GPU 加速持續改進。再加入各種不同方法使結果更好。
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