  Vision and text have been fully explored in contemporary video-text
foundational models, while other modalities such as audio and subtitles in
videos have not received sufficient attention. In this paper, we resort to
establish connections between multi-modality video tracks, including Vision,
Audio, and Subtitle, and Text by exploring an automatically generated
large-scale omni-modality video caption dataset called VAST-27M. Specifically,
we first collect 27 million open-domain video clips and separately train a
vision and an audio captioner to generate vision and audio captions. Then, we
employ an off-the-shelf Large Language Model (LLM) to integrate the generated
captions, together with subtitles and instructional prompts into omni-modality
captions. Based on the proposed VAST-27M dataset, we train an omni-modality
video-text foundational model named VAST, which can perceive and process
vision, audio, and subtitle modalities from video, and better support various
tasks including vision-text, audio-text, and multi-modal video-text tasks
(retrieval, captioning and QA). Extensive experiments have been conducted to
demonstrate the effectiveness of our proposed VAST-27M corpus and VAST
foundation model. VAST achieves 22 new state-of-the-art results on various
cross-modality benchmarks. Code, model and dataset will be released at
https://github.com/TXH-mercury/VAST.
