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Life Imitates ArtCubist Rendering of Photographs

Life Imitates ArtCubist Rendering of Photographs

15-869 Fall 06Zach Mouri

15-869 Fall 06Zach Mouri

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MotivationMotivation

Non-Photorealistic Rendering (NPR) Cubist styling of photographs

More “artistic”

Non-Photorealistic Rendering (NPR) Cubist styling of photographs

More “artistic”

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BackgroundBackground

Collomosse, J.P. and P. M. Hall. “Cubist Style Rendering of Photographs.” IEEE Transactions on Visualization and Computer Graphics. Volume 9 ,  Issue 4  (October 2003) pp 443 - 453

Collomosse, J.P. and P. M. Hall. “Cubist Style Rendering of Photographs.” IEEE Transactions on Visualization and Computer Graphics. Volume 9 ,  Issue 4  (October 2003) pp 443 - 453

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CubismCubism

…objects are broken up, analyzed, and re-assembled in an abstracted form…the artist depicts the subject from a multitude of viewpoints to present the piece in a greater context (http://en.wikipedia.org/wiki/Cubism)

Pablo Picasso, Georges Braque, Juan Gris

…objects are broken up, analyzed, and re-assembled in an abstracted form…the artist depicts the subject from a multitude of viewpoints to present the piece in a greater context (http://en.wikipedia.org/wiki/Cubism)

Pablo Picasso, Georges Braque, Juan Gris

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Cubist ArtCubist ArtThe Guitar, 1918

Juan Gris

Oil on Canvas

The Guitar, 1918

Juan Gris

Oil on Canvas

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Cubist ArtCubist Art

Three Musicians, 1921

Pablo Picasso

Oil on Canvas

Three Musicians, 1921

Pablo Picasso

Oil on Canvas

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Cubist ArtCubist Art

Guernica, 1937Pablo PicassoOil on Canvas

Guernica, 1937Pablo PicassoOil on Canvas

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ProcessProcess

Choose objects of interest Geometric distortion Feature composition Post-processing (optional)

Choose objects of interest Geometric distortion Feature composition Post-processing (optional)

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Identifying FeaturesIdentifying Features

“Salient” features Statistically uncommon pixels Spatially coherent clusters Manual grouping of high-level features

“Salient” features Statistically uncommon pixels Spatially coherent clusters Manual grouping of high-level features

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Identifying FeaturesIdentifying Features

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Geometric DistortionGeometric Distortion

Warp each feature image Distort curves angles Approximated with pincushion warp

Warp each feature image Distort curves angles Approximated with pincushion warp

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Geometric DistortionGeometric Distortion

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Selection and CompositionSelection and Composition

Select features Divide features into equivalence classes Compute set of intervals for each feature Pick random number; choose feature based on

interval Roughly equivalent to source images (two eyes,

one nose, two ears…)

Select features Divide features into equivalence classes Compute set of intervals for each feature Pick random number; choose feature based on

interval Roughly equivalent to source images (two eyes,

one nose, two ears…)

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Selection and CompositionSelection and Composition

Eyes Nose Ears

0 200 300 550

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Selection and CompositionSelection and Composition

Finer segmentation Determine average area of salient features Mask non-salient image portions Produce random, evenly distributed point cloud Construct Voronoi diagram Shade non-salient fragments using intensity

gradient

Finer segmentation Determine average area of salient features Mask non-salient image portions Produce random, evenly distributed point cloud Construct Voronoi diagram Shade non-salient fragments using intensity

gradient

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Selection and CompositionSelection and Composition

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Image RenderingImage Rendering

Color quantization Painter has restricted palette Introduce false color

Brush strokes Creates a “painterly” effect

Color quantization Painter has restricted palette Introduce false color

Brush strokes Creates a “painterly” effect

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ResultsResults Collomosse & Hall Collomosse & Hall

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ResultsResults

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ResultsResults

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Questions?Questions?