PORTRAIT PAINTING USING ACTIVE TEMPLATES Mingtian Zhao, Song-Chun - PowerPoint PPT Presentation

PORTRAIT PAINTING USING ACTIVE TEMPLATES Mingtian Zhao, Song-Chun Zhu University of California, Los Angeles Lotus Hill Institute http://bit.ly/portrait-painting

Portrait Painting • Particularity • Structural • Acute perception by human vision • Special Practices • Large and decisive brush strokes • Vibrant colors • Not so easy as painting generic objects

Painterly Rendering of Human Portraits • Existing Methods • Strategic [Hertzmann 98; Hays and Essa 04] • Content-Oriented [Zeng et al. 09] • Stochastic Processes [Zhao and Zhu 11]

Painterly Rendering of Human Portraits • Existing Methods • Strategic [Hertzmann 98; Hays and Essa 04] • Content-Oriented [Zeng et al. 09] • Stochastic Processes [Zhao and Zhu 11] • Challenges • Weak data vs. Strong prior • Large and decisive strokes: Structural details • Vibrant colors: Not present in original photographs • Our Approach • Example-Based Templates (Dictionary)

Portrait Painting Dictionary

Portrait Painting Dictionary

Portrait Painting Dictionary

Rendering Pipeline Stroke Position Stroke Color Transformation Shift

Rendering With Different Templates (Fig.1)

Active Portrait Template • Brush Stroke Model • [Zeng et al. 09] • Quadrilateral Mesh • Thin-Plate Spline (TPS) • Facial Structure Model • Active Appearance Model (AAM) • [Cootes 01] • 83 Landmark Points

Rendering • Template Selection • Compute AAM landmarks for input image • Search for best shape and color matching in the dictionary • Report 10 candidates for user selection • Shape distances in 5-D PCA space • Color distances in 25-D PCA space (Eigenface distance)

Rendering • Stroke Position Transformation • TPS transformation defined by pairs of AAM landmarks • Stroke Color Shift • Objective: To preserve contrast among neighboring strokes • Inspired by color transfer of natural images [Reinhard et al. 2001] • In CIELCH color space

Experiments (Fig.8)

Experiments (Fig.10)

Experiments (Fig.9)

Experiments (Fig.11)

Summary • A portrait painting method taking advantage of • Facial structure information • Techniques of artists • Future Work • Richer Representation • Better Color Processing • Part-Based Model

http://bit.ly/portrait-painting THANK YOU