Time-lapse photography captures a large amount of information about the lighting of a scene over a period of time. If this data is factored into its individual components – illumination, reflectance and shadows – the scene may be computationally re-lit for the purposes of advanced image editing operations. This program implements the Sunkavalli et al. 2007 approach to factored timelapses.
The algorithm involves splitting scene lighting into sunlight and skylight components:
- Read time-lapse video and mask sky pixels.
- For each colour channel, independently:
- Detect shadows.
- Extract skylight and the skylight basis curve.
- Extract sunlight and the sunlight basis curve.
- Reconstruct images and visualise results.
An in-depth description of how each component functions is detailed in the report.pdf file.