Abstract: We present an image-based technique to relight real objects illuminated by a 4D incident light field, representing the illumination of an environment. By exploiting the richness in angular and spatial variation of the light field, objects can be relit with a high degree of realism.

We record photographs of an object, illuminated from various positions and directions, using a projector mounted on a gantry as a moving light source. The resulting basis images are used to create a subset of the full reflectance field of the object. Using this reflectance field, we can create an image of the object, relit with any incident light field and observed from a fixed camera position.

To maintain acceptable recording times and reduce the amount of data, we propose an efficient data acquisition method.

Since the object can be relit with a 4D incident light field, illumination effects encoded in the light field, such as shafts of shadow or spot light effects, can be realized.