Estimating reflectance and shape of objects from a single cartoon-shaded image
Tóm tắt
Although many photorealistic relighting methods provide a way to change the illumination of objects in a digital photograph, it is currently difficult to relight digital illustrations having a cartoon shading style. The main difference between photorealistic and cartoon shading styles is that cartoon shading is characterized by soft color quantization and nonlinear color variations that cause noticeable reconstruction errors under a physical reflectance assumption, such as Lambertian reflection. To handle this non-photorealistic shading property, we focus on shading analysis of the most fundamental cartoon shading technique. Based on the color map shading representation, we propose a simple method to determine the input shading as that of a smooth shape with a nonlinear reflectance property. We have conducted simple ground-truth evaluations to compare our results to those obtained by other approaches.
Tài liệu tham khảo
Horn, B. K. P.; Brooks, M. J. Shape from Shading. Cambridge, MA, USA: MIT Press, 1989.
Khan, E. A.; Reinhard, E.; Fleming, R. W.; Bülthoff, H. H. Image-based material editing. ACM Transactions on Graphics Vol. 25, No. 3, 654–663, 2006.
Okabe, M.; Zeng, G.; Matsushita, Y.; Igarashi, T.; Quan, L.; Shum, H.-Y. Single-view relighting with normal map painting. In: Proceedings of Pacific Graphics, 27–34, 2006.
Wu, T.-P.; Sun, J.; Tang, C.-K.; Shum, H.-Y. Interactive normal reconstruction from a single image. ACM Transactions on Graphics Vol. 27, No. 5, Article No. 119, 2008.
Barla, P.; Thollot, J.; Markosian, L. X-toon: An extended toon shader. In: Proceedings of the 4th International Symposium on Non-Photorealistic Animation and Rendering, 127–132, 2006.
Lake, A.; Marshall, C.; Harris, M.; Blackstein, M. Stylized rendering techniques for scalable real-time 3D animation. In: Proceedings of the 1st International Symposium on Non-Photorealistic Animation and Rendering, 13–20, 2000.
Mitchell, J.; Francke, M.; Eng, D. Illustrative rendering in Team Fortress 2. In: Proceedings of the 5th International Symposium on Non-Photorealistic Animation and Rendering, 71–76, 2007.
DeCarlo, D.; Santella, A. Stylization and abstraction of photographs. ACM Transactions on Graphics Vol. 21, No. 3, 769–776, 2002.
Kang, H.; Lee, S.; Chui, C. K. Flow-based image abstraction. IEEE Transactions on Visualization and Computer Graphics Vol. 15, No. 1, 62–76, 2009.
Kyprianidis, J. E.; Döllner, J. Image abstraction by structure adaptive filtering. In: Proceedings of EG UK Theory and Practice of Computer Graphics, 51–58, 2008.
Winnemöller, H.; Olsen, S. C.; Gooch, B. Real-time video abstraction. ACM Transactions on Graphics Vol. 25, No. 3, 1221–1226, 2006.
Johnston, S. F. Lumo: Illumination for cel animation. In: Proceedings of the 2nd International Symposium on Non-Photorealistic Animation and Rendering, 45–52, 2002.
Sýkora, D.; Kavan, L.; Čadík, M.; Jamriška, O.; Jacobson, A.; Whited, B.; Simmons, M.; Sorkine-Hornung, O. Ink-and-ray: Bas-relief meshes for adding global illumination effects to hand-drawn characters. ACM Transactions on Graphics Vol. 33, No. 2, Article No. 16, 2014.
Shao, C.; Bousseau, A.; Sheffer, A.; Singh, K. CrossShade: Shading concept sketches using crosssection curves. ACM Transactions on Graphics Vol. 31, No. 4, Article No. 45, 2012.
Iarussi, E.; Bommes, D.; Bousseau, A. Bendfields: Regularized curvature fields from rough concept sketches. ACM Transactions on Graphics Vol. 34, No. 3, Article No. 24, 2015.
Xu, Q.; Gingold, Y.; Singh, K. Inverse toon shading: Interactive normal field modeling with isophotes. In: Proceedings of the Workshop on Sketch-Based Interfaces and Modeling, 15–25, 2015.
Wu, T.-P.; Tang, C.-K.; Brown, M. S.; Shum, H.-Y. ShapePalettes: Interactive normal transfer via sketching. ACM Transactions on Graphics Vol. 26, No. 3, Article No. 44, 2007.
Lopez-Moreno, J.; Jimenez, J.; Hadap, S.; Reinhard, E.; Anjyo, K.; Gutierrez, D. Stylized depiction of images based on depth perception. In: Proceedings of the 8th International Symposium on Non-Photorealistic Animation and Rendering, 109–118, 2010.
Orzan, A.; Bousseau, A.; Barla, P.; Winnemöller, H.; Thollot, J.; Salesin, D. Diffusion curves: A vector representation for smooth-shaded images. Communications of the ACM Vol. 56, No. 7, 101–108, 2013.
Kholgade, N.; Simon, T.; Efros, A.; Sheikh, Y. 3D object manipulation in a single photograph using stock 3D models. ACM Transactions on Graphics Vol. 33, No. 4, Article No. 127, 2014.
Lopez-Moreno, J.; Garces, E.; Hadap, S.; Reinhard, E.; Gutierrez, D. Multiple light source estimation in a single image. Computer Graphics Forum Vol. 32, No. 8, 170–182, 2013.
Grosse, R.; Johnson, M. K.; Adelson, E. H.; Freeman, W. T. Ground truth dataset and baseline evaluations for intrinsic image algorithms. In: Proceedings of IEEE 12th International Conference on Computer Vision, 2335–2342, 2009.
Rother, C.; Kiefel, M.; Zhang, L.; Schölkopf, B.; Gehler, P. V. Recovering intrinsic images with a global sparsity prior on reflectance. In: Proceedings of Advances in Neural Information Processing Systems 24, 765–773, 2011.