Shahlaei, Davoud: Single-image inverse lighting of faces with a virtual light stage. 2017
Content
- Abstract
- Zusammenfassung
- Acknowledgements
- Contents
- List of Tables
- List of Figures
- Chapter 1. Introduction
- 1.1 Motivation and Objectives
- 1.2 Input and Output of the Proposed Inverse Lighting
- 1.3 Contributions
- 1.4 Publications
- Chapter 2. Background and Related Work
- 2.1 Previous Work
- 2.2 The Appearance of Human Faces
- 2.3 Face Model Extraction with 3DMM from a 2D Image
- 2.3.1 The 3D Morphable Model (3DMM) of Faces
- 2.3.2 3DMM Fitting Algorithm and Joint Lighting Estimation
- 2.3.3 Model-Based Texture Extraction from 2D Image
- 2.4 Illumination Cone
- 2.4.1 Lighting Models
- 2.4.2 Light Sources
- 2.4.3 Light Stage
- 2.4.4 Formalizing the Superposition Principle
- 2.4.5 Estimation of RGB Parameters of Light Sources
- 2.5 Image Formation
- 2.5.1 Rendering
- 2.5.2 Phong Model
- 2.5.3 Torrance-Sparrow and Dipol Functions
- 2.5.4 Soft Cast Shadow Mapping
- 2.5.5 Color Correction
- 2.6 Cast Shadow Detection and Segmentation
- 2.7 Image Compression
- Chapter 3. Inverse Lighting and Relighting
- 3.1 The Inverse Lighting Framework
- 3.1.1 The Use Case Diagrams for the Proposed Inverse Lighting
- 3.1.2 An Activity Diagram for the Inverse Lighting Algorithm
- 3.2 To Span a Synthetic Illumination Cone
- 3.2.1 Virtual Light Stage (VLS)
- 3.2.2 Adopting a Measurement-Based Reflectance
- 3.2.3 Color Correction
- 3.2.4 3DMM Masks
- 3.3 Cast Shadow Detection and Segmentation
- 3.4 Image Compression
- 3.5 Inverse Lighting Algorithm with Superpixels
- 3.6 Relighting
- 3.7 An Effort to Improve the Estimated Shape after Inverse Lighting
- Chapter 4. Estimation by Optimization
- 4.1 Linear Model
- 4.2 Cost Function from the Generative Model
- 4.3 Maximum A-Posteriori (MAP)
- 4.4 Joint Maximum A-Posteriori (JMAP) for Hyperparameter Optimization
- 4.5 Optimization with Newton-Raphson
- 4.5.1 Enforcing Nonnegativity and Light-Weight Sparsity
- 4.5.2 The Hyperparameter Optimization Mechanism
- 4.5.3 Handling Occlusions and Areas of Misalignment
- 4.5.4 The Challenge of Cast Shadows
- 4.6 Implementation Tricks and Magic Numbers
- 4.7 Alternative Methods
- Chapter 5. Evaluation and Results
- 5.1 Mean Illumination SIMilarity (MISIM)
- 5.2 Results
- 5.2.1 Results of MAP
- 5.2.2 Ambiguity of the Estimated Lighting
- 5.2.3 The JMAP Results
- 5.2.4 Experiments with Different Number of Light Sources n
- 5.2.5 Experiments with Different Number of Superpixels ms
- 5.2.6 Cast Shadows
- 5.3 Relighting Results
- Chapter 6. Conclusion
- Index
- Bibliography
