Image-based rendering

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Image-based rendering focuses on rendering scenes from existing captured or rasterized images, typically from a new viewpoint.
Recent research allows adding new objects, performing relighting, and other AR effects.

Implicit Representations

Light Fields

Lightfields aim to capture the radiance of light rays within the scene.

Light Field Networks

This is an implicit representation similar to NeRF.
However, you directly predict colors from light rays instead of performing volume rendering.

NeRF

NeRF preprocesses unstructured light fields into a neural network (MLP) representation which predicts radiance at different points during volume rendering.

Resources

Layered Representations

Some notable people here are Noah Snavely and Richard Tucker.
Representations here vary from implicit (MPI, MSI) to explicit (LDI, Point Clouds).

Multi-plane Image (MPI)

Layered Depth Image (LDI)

Multi-sphere Image (MSI)

Point Clouds

Classical Reconstruction

Reconstruction aims to recreate the 3D scene from a set of input images.
Techniques include structure from motion, multi-view stereo.
This type of reconstruction is also studied in the field of photogrammetry.