While Large Vision-Language Models (VLMs) demonstrate impressive general visual capabilities, they remain artistically blind and unable to offer professional evaluation of artworks within specific artistic domains like human experts. To bridge this gap, we transform VLMs into experts capable of professional-grade painting evaluation in the Chinese Artistic Domain, which is more abstract and demands extensive artistic training for evaluation. We introduce HanMo-Bench, a new dataset that features authentic auction-grade masterpieces and AI-generated works, grounded in real-world market valuations. To realize the rigorous judgment, we propose the HanMoVLM and construct a Chain-of-Thought (CoT) validated by experts. This CoT guides the model to perform expert-level reasoning: from content identification and Region of Interest (RoI) localization to professional evaluation, guided by both theme-specific evaluation and typical three-tier evaluation in Chinese paintings. Furthermore, we design a reward function to refine the reasoning process of the HanMoVLM to improve the accuracy. We demonstrate that HanMoVLM can serve as a critical backbone for Test-time Scaling in image generation. By acting as a high-quality verifier, HanMoVLM enables generative models to select the most artistically superior outputs from multiple candidates. Experimental results and human studies confirm that the proposed HanMoVLM effectively bridges the gap, achieving a high consistency with professional experts and significantly improving the quality of Chinese Painting generation.
Figures & tables
Figure 1: The motivation of our study. (a) Generic VLMs suffer from artistic misalignment, evaluation gaps, and low-quality data when handling domain-specific artistic content such as Chinese paintings; (b) The expert-level VLMs introduce the structured expert chain-of-thought, to produce reliable final scores; (c) Experimental results show that our CoT and RL significantly improve performance.
Figure 2: The overall framework of HanMoVLM. For visual artistic understanding, we finetune HanMoVLM with expert-level CoT and expert answer via SFT, and then perform RFT based on the expert reward function. For visual artistic generation, we apply the frozen HanMoVLM as the external verifier to evaluate the images sampled from existing T2I models.
Figure 3: The expert-level Chain-of-Thought in our HanMoVLM. When the generic VLM evaluates Chinese paintings, the model tends to generate outputs based on general knowledge (non-expert) rather than following professional guidelines. As a result, its analysis does not reflect the experts’ procedures, leading to a decline in terms of professional level, reliability, hallucination, and human logic.
Figure 4: Composition of HanMo-Bench.
Figure 5: The construction pipeline of HanMo-Bench.
Model
Size
MAE↓
RMSE↓
Accuracy(%)↑
BERTScore↑
Proprietary Models
Gemini-3-Flash [ 13 ]
-
0.9883
1.3472
31.17
–
+ Thinking
-
0.9633
1.4355
34.83
0.3052
+ Expert CoT
-
0.9466
1.3351
37.00
0.3035
Gemini-3-Pro [ 13 ]
-
0.9866
1.3589
33.83
–
+ Thinking
-
0.9783
1.3311
35.17
0.2855
Table 1: The comparison of our HanMoVLM with other models. 10 and 10 indicate the best and second best results, respectively.
Model
Size
mIoU↑
BERTScore(RoI)↑
Theme↑
Qwen3-VL-Instruct
4B
0.0821
0.2852
0.7346
HanMoVLM (SFT)
4B
0.2708
0.4963
0.8305
HanMoVLM (RFT)
4B
0.2917
0.4911
0.8411
Qwen3-VL-Instruct
8B
0.1401
0.3214
0.7218
HanMoVLM (SFT)
8B
0.2835
0.4872
0.8355
HanMoVLM (RFT)
8B
0.3193
0.5126
0.8515
Table 2: The comparison in mIoU and Theme identification of our VLM with other models.
Figure 6: Generated results in different ratings groups (zoom in for details).
Figure 7: Generated results with the same prompt across different ratings.
Racc
RBERT
RmIoU
Accuracy (%) ↑
BERTScore ↑
mIoU ↑
✓
✓
42.18
0.5529
0.2914
✓
✓
42.36
0.5492
0.2728
✓
✓
39.82
0.5562
0.2902
✓
✓
✓
42.50
0.5568
0.2917
Table 3: The ablation study of using different rewards.
Figure 11Figure 12
Figure 12: The case of RoI in HanMoVLM and the corresponding predicted description and gt description in HanMoVLM. Zoom in for more details.
Rating Type
Top-1 Accuracy ↑
Accuracy ↑
Kendall’s τ↑
Spearman’s ρ↑
Aesthetic Score
0.045
0.125
-0.258
-0.282
PickScore [ 20 ]
0.409
0.341
0.106
0.073
HPSv2.1 [ 42 ]
0.364
0.193
-0.151
-0.173
GPT-4
0.227
0.341
0.197
0.218
GPT-5.1
0.273
0.364
0.121
0.209
HanMoVLM-8B
0.818
0.682
0.758
0.845
Table 4: Comparison of ranking accuracy in different models.
Figure 13: Visual results grouped by the score from our HanMoVLM. Zoom in for details.
Vision-language model-as-a-judge uses multimodal models to assess images, video, and visual-agent outputs against instructions, rubrics, or human preferences.
We introduce CARTBENCH, a museum-grounded benchmark for evaluating vision-language models (VLMs) on Chinese artworks beyond short-form recognition and QA. CARTBENCH comprises four subtasks: CURATORQA for evidence-grounded recognition and reasoning, CATALOGCAPTION for structured four-section expert-style appreciation, REINTERPRET for defensible reinterpretation with expert ratings, and CONNOISSEURPAIRS for diagnostic authenticity discrimination under visually similar confounds. CARTBENCH is built by aligning image-bearing Palace Museum objects from Wikidata with authoritative catalog pages, spanning five art categories across multiple dynasties. Across nine representative VLMs, we find that high overall CURATORQA accuracy can mask sharp drops on hard evidence linking and style-to-period inference; long-form appreciation remains far from expert references; and authenticity-oriented diagnostic discrimination stays near chance, underscoring the difficulty of connoisseur-level reasoning for current models.
Xuefeng Wei, Zhixuan Wang, Xuan Zhou +5
Nara Institute of Science and Technology · Liaoning Normal University
Pairwise preferences and pointwise ratings are the two dominant annotation protocols in image aesthetic assessment (IAA), yet existing benchmarks adopt only one, leaving their complementarity unmeasured under controlled conditions. We introduce PPaint, a matched dual-protocol benchmark in which 15 domain experts, 5 per category, annotate 150 Chinese paintings under both protocols across five aesthetic dimensions, collecting 45,900 pairwise expert judgments through a locally dense preference design alongside the matched ratings. The matched design reveals complementary strengths: preferences yield more consistent ordinal rankings, while ratings anchor the absolute score scale. Fusing both signals via two independent preference-to-score methods yields a fused expert ground truth on which the two constructions converge to nearly identical scores. The same preference-to-score principle extends to label-free VLM training. PSDistill converts VLM pairwise judgments into calibrated pseudo-scores via an Elo reference pool, and trains the same VLM with confidence-weighted ranking optimization to produce a single-pass aesthetic scorer. Trained on a single painting category, the distilled Qwen3-VL-8B improves mean SRCC from 0.504 to 0.709 across all three categories, outperforming all open-source baselines including the dedicated aesthetic model ArtiMuse and matching closed-source Gemini-3.1-Pro within 0.04 SRCC at single-pass inference cost, with cross-domain transfer further validated on APDDv2. We will release the full PPaint dataset and training code.
Yuanpei Zhao, Jie Lin, Chao Zhang +5
1Sichuan University · 2NetEase Fuxi AI Lab · †Work done during an internship at NetEase Fuxi AI Lab. +1
Vision-language models (VLMs) are increasingly used to detect whether AI-generated images contain visible artifacts, yet their ability to analyze such artifacts remains poorly understood. A correct image-level decision can still hide important failures: a model may correctly flag an artifact while relying on the wrong visual cue, selecting the wrong region, or describing a defect that the image does not support. To evaluate these behaviors directly, we introduce SalArt-VQA, a diagnostic benchmark for fine-grained SALient ARTifact understanding in AI-generated images. SalArt-VQA contains 950 images and 3,681 human-authored multiple-choice questions spanning artifact images, matched real reference images, and paired generated reference images. Four aligned question types evaluate presence detection, semantic localization, spatial grounding, and evidence-grounded defect identification, while the reference splits test calibration and abstention when the annotated defect is absent. Across 20 VLMs, SalArt-VQA reveals failures that image-level detection accuracy hides: the strongest model reaches 99.37% detection recall on artifact images but answers all four artifact-side questions correctly on only 53.26% of images. Comparing artifact images with artifact-free references reveals a sensitivity-calibration tradeoff: sensitive models often make unsupported artifact claims, while conservative models avoid false alarms largely by missing real artifacts. These results show that high artifact detection accuracy alone does not imply grounded artifact understanding. SalArt-VQA exposes these hidden failure modes and provides a fine-grained evaluation of whether VLM artifact claims are supported by local visual evidence.
Ruotian Zhang, Xiaoxiao Sun, Junzhe Huang +2
Zhejiang University · The University of Queensland