HelpingHand: Example-based Stroke Stylization Jingwan Lu Princeton University Fisher Yu Princeton University Adam Finkelstein Princeton University Presenter: Feilong yan Stephen DiVerdi Adobe Systems Inc. Painting Device A high quality stylus has 6 degrees of freedom (DOFs: 2D position, pressure, 2D tilt, and 1D rotation) (Note , at every point of trajectory) Examples of 6DOF 2D trajectory alone 6DoF A Painting with 6DoF Current Problems • Such devices are difficult for novices to control • The devices with 6DoFs are relatively expensive Is it possible to achieve 6DoFs with low quality devices and by novices? This Paper • Present a data driven method for synthesizing plausible pose data, optionally for synthesizing the stroke trajectory style. This Paper • Present a data driven method for synthesizing plausible pose data, optionally for synthesizing the stroke trajectory style. • Two underpinning assumptions observed: This Paper • Present a data driven method for synthesizing plausible pose data, optionally for synthesizing the stroke trajectory style. • Two underpinning assumptions observed: – Strokes of the same artist with similar trajectory are drawn with similar hand pose (for Pose Synthesis) This Paper • Present a data driven method for synthesizing plausible pose data, optionally for synthesizing the stroke trajectory style. • Two underpinning assumptions observed: – Strokes of the same artist with similar trajectory are drawn with similar hand pose (for Pose Synthesis) – Shapes of strokes are part of the “style” of a given artist (for Trajectory synthesis) Connection • With these two assumptions , we can use trajectory of stroke to query the library, whether pose or trajectory synthesis, the trajectory may be used to query Data Driven Approach Pose Synthesis Pose and Trajectory Synthesis Online Offline Pose & Trajectory Synthesis Query (2DoFs) Library of 6DoFs Strokes (By Artists) Output Offline • Collect a library of strokes with 6D data by trained artists • Compute the shape Feature Vectors (such as shape context) for every sample of the strokes, as the descriptor for comparison Online • Stroke by stroke • Compute the feature vectors for samples of the current query stroke • With feature vector, search for the K-NN for every sample. • For the current stroke, get the optimal sample sequence from library using Dynamic programming • Pose synthesis or trajectory synthesis Result Paper Stylization Online Offline Query (poor exposition) Sentence Synthesis Library of Beautiful Sentences Desired Paper Thank You