PREPARATION SYSTEMS FOR EFFICIENTLY GENERATING ALPHA MATTES AND MODIFIED DIGITAL VIDEOS UTILIZING POLARIZED LIGHT

The present disclosure relates to systems, non-transitory computer-readable media, and methods for efficiently automating the preparation of accurate alpha matte animations and modified digital videos utilizing polarized light. For example, the disclosed systems obtain a plurality of polarized digital videos portraying an animation of a foreground subject backlit by a polarized light source. In some embodiments, the disclosed systems generate a plurality of corrected polarized digital videos by adjusting intensity values of the plurality of polarized digital videos based on intensity differences across the plurality of polarized digital videos. The disclosed systems generate an alpha matte animation comprising a plurality of alpha mattes from the plurality of corrected polarized digital videos or from the plurality of polarized digital videos. Utilizing the alpha matte animation, the disclosed systems generate a modified digital video by combining the animation of the foreground subject and a replacement background.