There are many more weird and complex architectures in models for video understanding.

For example, beyond video->text->llm and video->embedding in llm, you can also have an llm controlling/guiding a separate video extractor.

See this paper for a pretty thorough overview.

Tang, Y., Bi, J., Xu, S., Song, L., Liang, S., Wang, T., Zhang, D., An, J., Lin, J., Zhu, R., Vosoughi, A., Huang, C., Zhang, Z., Liu, P., Feng, M., Zheng, F., Zhang, J., Luo, P., Luo, J., & Xu, C. (2025). Video Understanding with Large Language Models: A Survey (No. arXiv:2312.17432). arXiv. https://doi.org/10.48550/arXiv.2312.17432