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Image-based rendering (IBR) revolutionizes 3D graphics by enhancing realism through advanced techniques. The 1st wave focuses on brute-force image-space methods, leveraging texture maps, mipmapping, z-buffers, and shadows. The 2nd wave moves beyond traditional polygons, enabling environment representation via formats like QuickTimeVR and light fields. With applications in interactive graphics, museums, and games, IBR offers a cost-effective approach to capturing complex scenes and environments with reduced computational demands. Discover the evolution and future directions of this innovative rendering technology.
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Image-Based Rendering: 1st Wave • Definition: Using images to enhance the realism of 3D graphics • Brute Force in Image-Space, L. Williams • Texture maps for surface detail • Mipmapping (antialiasing) • Zbuffers for hidden surfaces • Shadow mattes and maps • Object tags
Image-Based Rendering: 2nd Wave • Represent (model and render) environments without using traditional geometric representations (polygons) • Examples • QuickTimeVR and panoramic image representations • Light fields or virtual holograms • Color + Range images • Coupling viewing and morphing • Advantages • Cost independent of scene complexity • Imagery from real or virtual scenes • Modest computation compared to classical C.G.
Applications • Capture 3D environments • MIT’s ASPEN MovieMap, Cyan’s MYST and RIVEN • Museums, real estate, products, sets, planets • Interactive 3D Graphics and Games • Representations of complex environments (lod) • Background environments • Textured portals • 3D sprites, billboards and imposters • Post rendering warps • Frame interpolation, priority rendering (Talisman) • Latency compentation: HMDs, networked telepresence • Stereo from single RGBZ image
Apple’s QuickTime VR Outward Inward
History of Panoramas • Robert Barker’s Panorama (1792) • 50’ high, 400’ circumference, platform for viewing • Raoul Brimoin-Sanson’s Cineorama (1897) • 10 synchronized projectors, 300’ circumference • Disney’s CircleVision • 9 35mm projectors • Mirrored panoramic camera • Modern IMAX and OMNIMAX theaters
Panoramic Cameras • Rotating Cameras • Kodak Cirkut • Globuscope • Stationary Cameras • Be Here
Creating a Cylindrical Panorama From www.quicktimevr.apple.com
Stitching • Prewarping Lens Distortion, Radiometry,Cylindrical projection • Image Registration Feature alignment,Pixel difference minimization, Fourier correlation • Global Alignment Gap closingMutual image aligment • Compositing Blending,Nearest Neighbor Example courtesy James Davis
Commercial Products • QuickTime VR, LivePicture, IBM (Panoramix) • VideoBrush • IPIX (PhotoBubbles), Be Here, etc.
Future Directions • Geometry + panoramas • Hot spots • Hierarchical panoramas • Stereo / depth-mapped panoramas • Video panoramas
Light Field • Key Ideas: • 4D function - Valid outside convex hull • 2D slice = image - Insert to create - Extract to display • Inward or outward
Two Plane Parametrization Object Focal plane (st) Camera plane (uv)
Original prototype gantry • Issues: focal plane, aperture, support, lighting
New light field gantry • Applications: • digitizing light fields • measuring BRDFs • range scanning • Designed by • Marc Levoy et al.
Light Field Camera prototype (32 z 2) long-term goal (32 z 32) Concept: Pat Hanrahan Mark Horowitz Marc Levoy compression chip imaging chip light field
