Although Multimodal Large Language Models (MLLMs) have demonstrated proficiency in video captioning, practical applications require captions that follow specific user instructions rather than generating exhaustive, unconstrained descriptions. Current benchmarks, however, primarily assess descriptive comprehensiveness while largely overlooking instruction-following capabilities. To address this gap, we introduce IF-VidCap, a new benchmark for evaluating controllable video captioning, which contains 1,400 high-quality samples. Distinct from existing video captioning or general instruction-following benchmarks, IF-VidCap incorporates a systematic framework that assesses captions on two dimensions: format correctness and content correctness. Our comprehensive evaluation of over 20 prominent models reveals a nuanced landscape: despite the continued dominance of proprietary models, the performance gap is closing, with top-tier open-source solutions now achieving near-parity. Furthermore, we find that models specialized for dense captioning underperform general-purpose MLLMs on complex instructions, indicating that future work should simultaneously advance both descriptive richness and instruction-following fidelity.
@article{arxiv.2510.18726,
title = {IF-VidCap: Can Video Caption Models Follow Instructions?},
author = {Shihao Li and Yuanxing Zhang and Jiangtao Wu and Zhide Lei and Yiwen He and Runzhe Wen and Chenxi Liao and Chengkang Jiang and An Ping and Shuo Gao and Suhan Wang and Zhaozhou Bian and Zijun Zhou and Jingyi Xie and Jiayi Zhou and Jing Wang and Yifan Yao and Weihao Xie and Yingshui Tan and Yanghai Wang and Qianqian Xie and Zhaoxiang Zhang and Jiaheng Liu},
journal= {arXiv preprint arXiv:2510.18726},
year = {2025}
}