1 / 12

A unified model of specular and diffuse reflectance for rough, glossy surfaces

A unified model of specular and diffuse reflectance for rough, glossy surfaces. William A.P. Smith and Edwin R. Hancock Department of Computer Science, University of York, UK CVPR 2009 Reporter: Annie Lin . Introduction.

frisco
Télécharger la présentation

A unified model of specular and diffuse reflectance for rough, glossy surfaces

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. A unified model of specular and diffuse reflectance for rough, glossy surfaces William A.P. Smith and Edwin R. Hancock Department of Computer Science, University of York, UK CVPR 2009 Reporter: Annie Lin

  2. Introduction • A unified model of specular and diffuse reflectance from microfacet model by describing both components of reflectance In terms of Fresnel theory and the same model of surface roughness. －－－Parameter estimations that all have physical meaning. • Reflectance from surfaces • Surface Roughness model • A unified model • Masking and shadowing of microfacets • Fresnel reflectance • Specular reflectance • Diffuse reflectance

  3. Reflectance from surfaces • If the illumination, viewer and normal direction vectors are specified in global coordinate

  4. Surface Roughness model • Slope area distribution • [7] Torrance and Sparrow • Represent the number of facets per unit surface roughness

  5. A unified model • The model requires only three physically meaningful parameters: • The refractive index of the surface ( ) • The surface roughness ( ) • The albedo of the surface ( )

  6. Masking and shadowing of microfacets • [5] Oren and Nayar • Fresnel reflectance • Fresnel’s equation: • Compute the proportion of light that is secularly reflected form the surface and that which enters the surface and is subsequently diffusely reflected

  7. Specular reflectance • Only those microfacets hose normal vectors lie within a solid angledw’ around the vector H , halfway between the light source and viewer , are capable of secularly reflecting light into the solid angle dw, around the view direction vector

  8. Diffuse reflectance • Radiance from a Lambertian patch • Diffuse radiance from a rough surface composed of shiny microfacets • the remaining proportion of the incident light • Account shadowing of the light source and Fresnel transmission into the surface

  9. Characteristics of the diffuse model

  10. Experiments • The combination model:

More Related