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Animating Animal Motion From StillPresenting:Shahar Ben EzraSaar NakibliSupervisor: Hayley Binia WolmanComputer Graphics LabElectrical Engineering, Technion, Israel June 2009

[1] [1] Xuemiao Xu , Animating Animal Motion From Still, Siggraph 2008

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1Project GoalCreate an animation movie by reconstructing the animal motion from a still picture

Algorithm

Still ImageAnimation Movie , , : ,:

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2OverviewShape Context Descriptor

Find distancesPath Finding6,3,4,1,2,5Consistency RefinementTPSMorphingCreating AnimationsnapshotsShape context descriptorsDistances matrixMotion PathConsistent snapshotsAnimation between two snapshotsFinal Movie

Source ImageSnapshot Extraction

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.3Shape Context

Find the contour of the snapshot

For every point on the contour draw the circles and bins as shown

Create the matrix descriptor

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: 4Distance Matrix

Distance between Snapshot-K and Snapshot-L:Point on snapshot KClosest point on snapshot LHow do we find ?

Distance between two matrix descriptors ., "" ., K L K L. ( ) .

MATRIX DESCRIPTOR .

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5Path Finding Find the optimal path between the snapshots using the distances matrixEnergy function of path:Avoid getting stuck on a local minimum by using Simulated Annealing Optimization Algorithm, which allows us to exit a local minimum.

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, . , outliers, .6Motion CycleFull Cycle:Half Cycle:

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7Pose Consistency

Pivot

In order to create smooth and realistic animation, all the animals have to be in the same pose relative to the camera.Affine transformation includes: Translation scale rotationAll snapshots are translated relative to a pivot snapshot. . , , . , , . , .

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Appearance ConsistencyPivot histogram:Every snapshot has its own color and texture that can vary from one snapshot to another.

Histograms standardization of all snapshots will make the final animation look smoother.

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...9TPS Morphing

Finding animation points: Points which are not static during the animal motion

Morph between the source points and target pointsSource Image is registered to the green pointsDestination Image is registered to the red points.

. MORPHING . . , . ... .10Creating AnimationMorph three frames between two snapshots

SourceDestination0.750.250.50.50.750.25

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11Results

Tadpoles:Turtles:Ready? Go!.

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