  Previous research has studied the task of segmenting cinematic videos into
scenes and into narrative acts. However, these studies have overlooked the
essential task of multimodal alignment and fusion for effectively and
efficiently processing long-form videos (>60min). In this paper, we introduce
Multimodal alignmEnt aGgregation and distillAtion (MEGA) for cinematic
long-video segmentation. MEGA tackles the challenge by leveraging multiple
media modalities. The method coarsely aligns inputs of variable lengths and
different modalities with alignment positional encoding. To maintain temporal
synchronization while reducing computation, we further introduce an enhanced
bottleneck fusion layer which uses temporal alignment. Additionally, MEGA
employs a novel contrastive loss to synchronize and transfer labels across
modalities, enabling act segmentation from labeled synopsis sentences on video
shots. Our experimental results show that MEGA outperforms state-of-the-art
methods on MovieNet dataset for scene segmentation (with an Average Precision
improvement of +1.19%) and on TRIPOD dataset for act segmentation (with a Total
Agreement improvement of +5.51%)
