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arXiv · 2510.25225

Hallucination Localization in Video Captioning

Shota Nakada·Kazuhiro Saito·Yuchi Ishikawa·Hokuto Munakata·Tatsuya Komatsu·Masayoshi Kondo
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Abstract

We propose a novel task, hallucination localization in video captioning, which aims to identify hallucinations in video captions at the span level (i.e. individual words or phrases). This allows for a more detailed analysis of hallucinations compared to existing sentence-level hallucination detection task. To establish a benchmark for hallucination localization, we construct HLVC-Dataset, a carefully curated dataset created by manually annotating 1,167 video-caption pairs from VideoLLM-generated captions. We further implement a VideoLLM-based baseline method and conduct quantitative and qualitative evaluations to benchmark current performance on hallucination localization.

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Shota Nakada, Kazuhiro Saito, Yuchi Ishikawa, Hokuto Munakata, Tatsuya Komatsu, Masayoshi Kondo. 2025-10-29. Hallucination Localization in Video Captioning. https://arxiv.org/abs/2510.25225

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