Recomendados
Recomendados
Mais conteúdo relacionado
Mais procurados
Mais procurados (20)
Semelhante a Incident light field 1
Semelhante a Incident light field 1 (20)
Último
Último (20)
Incident light field 1
- 1. Incident Light Field The distribution of light in a static scene with a fixed illumination Dr. Kurt Debattista Prof. Alan Chalmers Debmalya Sinha
- 2. Courtesy: J. Unger / Linköping University Synthetic objects on a physical table with real life lighting
- 3. Acquisition Dynamic or Static Large Camera Array, Mirror sphere, Plane Mirror, HDR video, SfM (structure from motion) Physical Scene Representation 2PP PDP 2SP DPP Rendering Storage Virtual Scene
- 4. 1. Image Based Lighting 2. Light Field Incident Light Field We require an Environment Map A Panoramic image of the environment that envelops the object space we’re about to Render.
- 5. 1. Image Based Lighting 2. Light Field Incident Light Field Courtesy: nVidia
- 6. 1. Image Based Lighting 2. Light Field Incident Light Field We take several pictures from spatially varying points on the camera plane. Each of the pictures differ a little by angle Courtesy: Pat Hanrahan / Stanford University
- 7. 1. Image Based Lighting 2. Light Field Incident Light Field
- 8. 1. Image Based Lighting 2. Light Field Incident Light Field
- 9. 1. Image Based Lighting 2. Light Field Incident Light Field The distribution of light in a static scene with a fixed illumination We take separate environment map of each little segments of the space to record the incident light rays on the entire object space we are about to render.
- 10. Courtesy: J. Unger / Linköping University
- 11. Acquisition Dynamic or Static Large Camera Array, Mirror sphere, Plane Mirror, HDR video, SfM (structure from motion) Physical Scene Representation 2PP PDP 2SP DPP Rendering Storage Virtual Scene
- 12. Representation Represented by 7 dimension Plenoptic function on a point P θ,φ -> direction of light ray from P, λ -> wavelength of incident light, t -> time Vx,Vy,Vz -> Cartesian coordinate of P. P = P(θ,φ,λ,t,Vx,Vy,Vz) Which can be reduced to a 4D function P = P(θ,φ,u,v) Assuming, the incident light only comes from the upper hemisphere of the surface [Vx,Vy] ([u,v]). 0 ≤ φ ≤ π/2 and -π ≤ θ ≤ π Plenoptic parameterization Acq uisit ion Physical Scene Repres entatio n Renderin g Stora ge Virtual Scene
- 13. Representation Acq uisit ion Physical Scene Repres entatio n Renderin g Stora ge Virtual Scene 2PP PDP 2SP DPP Line Space parameterization Two Points on Two Planes A Point and a Direction Two Points on a Sphere A Direction and a Point 2PP 2SP PDP DPP Courtesy: Camahort et al.
- 14. Acquisition Dynamic or Static Large Camera Array, Mirror sphere, Plane Mirror, HDR video, SfM (structure from motion) Physical Scene Representation 2PP PDP 2SP DPP Rendering Storage Virtual Scene
- 15. Acquisition Acq uisit ion Physical Scene Repres entatio n Renderin g Stora ge Virtual Scene Light Probes A Light Probe is an omni-directional (360° panoramic) high-dynamic range image. (Debevec et al.) • Typically a highly reflective silvered ball is used. • An HDR Image is taken of the ball. Problems: • The image has the reflection of the camera itself. • Has to take two images from different direction to get rid of the reflection of camera. • The edges are stretched badly and needs efficient warping.
- 16. Acquisition Acq uisit ion Physical Scene Repres entatio n Renderin g Stora ge Virtual Scene Light Probes for ILF Techniques • Single HDR image of Light probe • HDR video of a moving Light Probe • HDR video from fisheye lens • Light Probe Array • Plain Mirror (edge coded) Edge coded plain mirror - Courtesy: Ihrke et al. / INRIA Labs Mirror Sphere array - Courtesy: Dr. J. Unger HDR video with fisheye lens - Courtesy: Dr. J. Unger
- 17. Acquisition Acq uisit ion Physical Scene Repres entatio n Renderin g Stora ge Virtual Scene Light Probes for ILF Problems of mirror sphere array • Reflection from other Mirrors • Camera reflection Problems of HDR Video setup • Impractical for big space
- 18. AcquisitionProposals 1. Bowls are better than Balls: Concave light probes to eliminate mutual reflection 2. 3D space coverage: 45* angle concave probe plane to capture uneven surface such as race tracks Far fetched idea: probe fitted in a Quadraptor! Acq uisit ion Physical Scene Repres entatio n Renderin g Stora ge Virtual Scene Blocked for obvious reasons !
- 19. AcquisitionProposals 1. Bowls are better than Balls: Concave light probes to eliminate mutual reflection 2. 3D space coverage: 45* angle concave probe plane to capture uneven surface such as race tracks Far fetched idea: probe fitted in a Quadraptor! Acq uisit ion Physical Scene Repres entatio n Renderin g Stora ge Virtual Scene 1 2 3 4 5 6 7 Move Direction Blocked for obvious reasons !
- 20. AcquisitionProposals 1. Bowls are better than Balls: Concave light probes to eliminate mutual reflection 2. 3D space coverage: 45* angle concave probe plane to capture uneven surface such as race tracks Far fetched idea: probe with a gimbal fitted in a Quadraptor! Acq uisit ion Physical Scene Repres entatio n Renderin g Stora ge Virtual Scene Little inefficient for covering large space provides much more mobility than a fixed camera setup Blocked for obvious reasons !
- 21. Acquisition Physical Scene Representation Rendering Storage Virtual Scene ToDoin the next months • Re-creating the ILF acquisition with spherical probe. • Implementing it into PARC • Comparing to original results in terms of Rendering Artifacts • Seam • Hair • Pixelation • Ghosting • Disparity problem
- 22. Questions?