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Digital Image Stabilization

教師 : 楊士萱 老師學生 : 鄭馥銘

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Outline

Introduction of DIS DIS work flow chart Current work Experiment result Future work

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Introduction of DIS

Video footage from hand-held DV is typically jerky due to small, unwanted DV movement

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Introduction of DIS

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Introduction of DIS

A DIS system aims to produce a compensated video sequence so that the image motion due to the camera’s undesirable shake or jiggles can be removed

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DIS work flow chart

Block-Blased Motion Estimation

Do DIS?

MV Validation

MVs

LMVs

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DIS flow chart

FMV Generation

Hand – shake Estimation

Motion correction

LMVs

FMVs

SMV , HMV , AMV

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Current work - ME

Block-Blased Motion Estimation

Do DIS?

MV Validation

MVs

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Current work - ME

Block-based motion estimation– Using Y in YCBCr ,MAD as the distortion measure– MB size = 16 * 16– Pixel depth = 8– Resolution = ½– Search range = 32 or 64– Full search

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Current work – do DIS?

Block-Blased Motion Estimation

Do DIS?

MV Validation

MVs

Not yet

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Current work – MV Validation

Block-Blased Motion Estimation

Do DIS?

MV Validation

LMVs

MVs

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Current work – MV Validation

Eliminate the Motion Vectors that effect to obtain frame Motion Vector(FMV).– Repeated pattern– Moving object

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Current work – FMV Generation

FMV Generation

Hand – Shake Estimation

Motion Correction

LMVs

FMV

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Current work – FMV Generation

Compute the FMV form LMVs– Median of LMVs– Mean of LMVs– Majority of LMVs that had counted amount of

direction

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Current work – Hand Shake Est

FMV Generation

Hand – Shake Estimation

Motion Correction

LMVs

FMV

SMV , HMV , AMV

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Current work – Hand Shake Est

FMV = SMV(steady motion vector) + HMV(Hand Shake)

SMV– Mean of post FMVs in buffer– Motion Vector Integration

( SMV(n) = αSMV(n-1) + βFMV(n) ) HMV(n) = FMV(n) – SMV(n) AMV(n) = AMV(n-1) + HMV(n)

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Current work – Motion Correction

FMV Generation

Hand – Shake Estimation

Motion Correction

LMVs

FMV

SMV , HMV , AMV

AMV

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Experiment result1 – sport videoSMV = Mean of post FMVs in buffer

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Experiment result1 – sport videoHMV(n) = FMV(n) – SMV(n)

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Experiment result1 – sport videoFrequency response of FMV & SMV

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Experiment result2 – sport videoSMV(n) = αSMV(n-1) + βFMV(n)

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Experiment result2 – sport videoHMV(n) = FMV(n) – SMV(n)

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Experiment result2 – sport videoFrequency response of FMV & SMV

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Future work

Block-Blased Motion Estimation

Do DIS?

MV Validation

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Future work

FMV Generation

verify mean & median & majority result MV Validation

– MVI method SMV(n) = αSMV(n-1) + βFMV(n) How to choose α and β. ?

Spare MBs for foreground and background ?

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Future work

Finding or making video suit with DIS testing Implement DIS system in DM270