Kanchana Ranasinghe, Xiang Li, Kumara Kahatapitiya, Michael S. Ryoo
Large Language Models (LLMs) have allowed recent LLM-based approaches to achieve excellent performance on long-video understanding benchmarks. We investigate how extensive world knowledge and strong reasoning skills of underlying LLMs influence this strong performance. Surprisingly, we discover that LLM-based approaches can yield surprisingly good accuracy on long-video tasks with limited video information, sometimes even with no video specific information. Building on this, we exploring injecting video-specific information into an LLM-based framework. We utilize off-the-shelf vision tools to extract three object-centric information modalities from videos and then leverage natural language as a medium for fusing this information. Our resulting Multimodal Video Understanding (MVU) framework demonstrates state-of-the-art performance across multiple video understanding benchmarks. Strong performance also on robotics domain tasks establish its strong generality. Our code will be released publicly.
| Task | Dataset | Metric | Value | Model |
|---|---|---|---|---|
| Question Answering | NExT-QA | Accuracy | 55.2 | MVU (13B) |
| Question Answering | EgoSchema (fullset) | Accuracy | 37.6 | MVU (13B) |
| Question Answering | EgoSchema (subset) | Accuracy | 60.3 | MVU (13B) |
| Question Answering | EgoSchema (subset) | Inference Speed (s) | 2.42 | MVU (13B) |
| Video Question Answering | NExT-QA | Accuracy | 55.2 | MVU (13B) |
| Video Question Answering | EgoSchema (fullset) | Accuracy | 37.6 | MVU (13B) |
| Video Question Answering | EgoSchema (subset) | Accuracy | 60.3 | MVU (13B) |
| Video Question Answering | EgoSchema (subset) | Inference Speed (s) | 2.42 | MVU (13B) |