Image Warping - TAUdcor/Graphics/pdf.slides/... · 2017. 4. 24. · Forward Mapping -Disadvantages....

ImageWarping

ImageMapping

ImageMapping- Examples

ForwardMapping

ForwardMapping- Disadvantages

Example– ForwardMappingOriginal Rotated

ZoomIn

BackwardMapping

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TheProblem:(u,v)arenotintegers!

NearestNeighbor

Example- NearestNeighborOriginal Rotated

ZoomIn

Bi-linearInterpolation• Bi-linearinterpolatesfourclosestpixels.• Theweightforeachpixelisproportionaltoitsdistancefromthesamplingpoint(x,y)

Bi-linearInterpolation

ExampleBi-linearOriginal Rotated

ZoomIn

Bi-cubic

• Bicubic interpolates16closestneighbors(4x4neighborhood)• Theresultismuchmoresmooth

Bi-cubicInterpolation

ExampleBi-cubicOriginal Rotated

ZoomIn

NearestNeighbor

Bi-LinearInterpolation

Bi-CubicInterpolation

ComparisonNearestNeighbor Bi-linear Bi-cubic

DirectRotation

ShearandScaleOperatinglinebyline,fasterandsimplerfilters

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Image Warping - TAUdcor/Graphics/pdf.slides/... · 2017. 4. 24. · Forward Mapping -Disadvantages....

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Transcript of Image Warping - TAUdcor/Graphics/pdf.slides/... · 2017. 4. 24. · Forward Mapping -Disadvantages....

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