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Mitigating Object Hallucinations in Large Vision-Language Models through Visual Contrastive Decoding

28 Nov 2023CVPR 2024 1arXiv:2311.16922archive 2025-07-28

Sicong Leng, Hang Zhang, Guanzheng Chen, Xin Li, Shijian Lu, Chunyan Miao, Lidong Bing

Large Vision-Language Models (LVLMs) have advanced considerably, intertwining visual recognition and language understanding to generate content that is not only coherent but also contextually attuned. Despite their success, LVLMs still suffer from the issue of object hallucinations, where models generate plausible yet incorrect outputs that include objects that do not exist in the images. To mitigate this issue, we introduce Visual Contrastive Decoding (VCD), a simple and training-free method that contrasts output distributions derived from original and distorted visual inputs. The proposed VCD effectively reduces the over-reliance on statistical bias and unimodal priors, two essential causes of object hallucinations. This adjustment ensures the generated content is closely grounded to visual inputs, resulting in contextually accurate outputs. Our experiments show that VCD, without either additional training or the usage of external tools, significantly mitigates the object hallucination issue across different LVLM families. Beyond mitigating object hallucinations, VCD also excels in general LVLM benchmarks, highlighting its wide-ranging applicability.

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damo-nlp-sg/vcd officialmentioned in papermentioned on GitHubpytorchApache-2.0 report
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get_abs_pos damo-nlp-sg/vcd/experiments/Qwen_VL/visual.py official repository ran · our draft was wrong fingerprinted Apache-2.0 (permissive) · 50c4398a8645438a · report
get_batch damo-nlp-sg/vcd/experiments/Qwen_VL/qwen_generation_utils.py official repository ran Apache-2.0 (permissive) · d2c4545e71293dec · report
get_chunk damo-nlp-sg/vcd/experiments/eval/object_hallucination_vqa_instructblip.py official repository ran · our draft was wrong fingerprinted Apache-2.0 (permissive) · 42a46570620cd9fa · report
get_ltor_masks_and_position_ids damo-nlp-sg/vcd/experiments/Qwen_VL/qwen_generation_utils.py official repository ran Apache-2.0 (permissive) · 2d28c844d3557fe6 · report
pad_batch damo-nlp-sg/vcd/experiments/Qwen_VL/qwen_generation_utils.py official repository ran Apache-2.0 (permissive) · a83d13d0950d1a06 · report
split_list damo-nlp-sg/vcd/experiments/eval/object_hallucination_vqa_instructblip.py official repository ran · our draft was wrong fingerprinted Apache-2.0 (permissive) · 076c252c52cbb161 · report
tile damo-nlp-sg/vcd/experiments/lavis/models/base_model.py official repository ran fingerprinted Apache-2.0 (permissive) · cb33571427334815 · report
add_diffusion_noise damo-nlp-sg/vcd/vcd_utils/vcd_add_noise.py official repository unverified Apache-2.0 (permissive) · fe66de066c32d0fc · report
all_gather_with_grad damo-nlp-sg/vcd/experiments/lavis/models/base_model.py official repository unverified Apache-2.0 (permissive) · 0ec9fc2025c16f65 · report
apply_rotary_pos_emb damo-nlp-sg/vcd/experiments/Qwen_VL/modeling_qwen.py official repository unverified Apache-2.0 (permissive) · fbda921818ec02df · report
get_2d_sincos_pos_embed_from_grid damo-nlp-sg/vcd/experiments/Qwen_VL/visual.py official repository unverified Apache-2.0 (permissive) · 2884deadbb637c3e · report
sample damo-nlp-sg/vcd/vcd_utils/vcd_sample.py official repository unverified Apache-2.0 (permissive) · 265b8739e27fe5c8 · report
recorder huofushuo/SID/pope_eval.py community (archive-listed) ran · our draft was wrong no licence file found · pointer only · a06c0813244b6279 · report

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