Pretrained vision-language models such as CLIP excel at zero-shot recognition but often fail at compositionality, particularly attribute-object and relational structures. Recent studies mitigate this issue by augmenting training with synthetic hard negatives generated by a cascade of large language models and text-to-image models, which incurs substantial pipeline overhead. We instead propose MLLMCLIP, a heterogeneous distillation framework that transfers multimodal knowledge directly from a generative Multimodal Large Language Model (MLLM) teacher into a discriminative CLIP student, bypassing synthetic data entirely. To bridge the architectural mismatch between the two paradigms, we introduce an attention-based per-layer token selection and a CKA-based distillation loss. Compared to prior CLIP-enhancement methods, MLLMCLIP achieves state-of-the-art compositional accuracy while delivering consistent gains on standard zero-shot classification and image-text retrieval, showing that feature-level distillation strengthens both compositional and general vision-language representation capability.
Figures & tables
Figure 1: Two distillation paradigms. ( 1(a) ) Prior methods synthesize hard-negative samples via cascaded LLM and image generators. ( 1(b) ) We distill hidden states from a frozen MLLM into CLIP directly.
Type
Model (Backbone)
First
Second
Avg.
MLLM
LLAVA-1.6-mistral-7B
95.6
74.3
85.0
LLaMA-3.2-Vision-11B
92.1
92.5
92.3
Qwen2-VL-2B
88.9
95.4
92.2
Qwen3-VL-2B
94.0
95.0
94.5
Qwen3.5-2B
88.5
96.0
92.3
InternVL3.5-2B
94.2
89.4
91.8
Table 1: SugarCrepe accuracy of representative MLLM-as-judge and embedding-based teachers. Embedding models are position-invariant; full results are in Table F .
Figure 2: Overview of the MLLMCLIP framework. Student features are passed through auxiliary layers before alignment, and attention-based token selection obtains salient teacher tokens.
Method
External Source
ARO
CREPE
EQBEN
ImageCODE
SugarCrepe
SvoProbes
VALSE
VLChecklist
WhatsUp
Winoground
SPEC
Average
CLIP
–
35.6
11.6
14.8
15.0
59.7
75.8
55.1
64.5
41.3
7.00
28.5
37.1
LaCLIP
LLAMA-7B
35.2
9.98
14.4
14.8
64.0
76.9
56.6
64.8
41.5
4.75
28.3
37.5
NegCLIP
Qwen3-4B
36.2
11.7
14.8
15.8
62.4
76.3
56.1
64.0
40.9
7.00
28.2
37.6
FSC-CLIP
Qwen3-4B
35.1
9.86
16.3
14.9
63.8
78.8
57.4
64.4
41.8
5.50
29.2
38.0
TripletCLIP
Qwen3-4B, SDXL-Turbo
34.6
10.5
16.4
16.9
65.7
78.8
59.4
64.8
41.1
4.25
29.0
38.3
MLLMCLIP (Ours)
LLaVA-1.6-Mistral-7B
32.1
10.7
15.5
15.6
69.3
79.4
55.9
64.6
43.6
7.25
26.5
38.2
Table 2: Performance on 11 compositionality benchmarks.
Method
External Source
Caltech 101
CIFAR-10
CIFAR-100
DTD
EuroSAT
FER 2013
Flower 102
Food 101
ImageNet
KITTI
Pet
RESISC45
VOC 2007
Average
CLIP
–
37.8
53.3
21.7
7.93
12.1
12.4
8.88
8.91
12.4
20.0
9.95
15.9
54.0
21.2
LaCLIP
LLAMA-7B
41.7
49.7
21.2
11.2
14.3
19.5
11.2
9.34
13.7
30.7
10.1
17.1
60.9
23.9
NegCLIP
Qwen3-4B
41.4
55.3
24.1
10.6
18.3
18.9
9.16
9.49
13.7
30.4
8.81
17.9
56.8
24.2
FSC-CLIP
Qwen3-4B
41.5
54.2
25.1
9.84
18.0
16.8
9.03
9.40
13.5
20.8
10.1
20.3
63.1
24.0
TripletCLIP
Qwen3-4B, SDXL-Turbo
42.4
46.5
22.3
13.5
24.6
17.2
10.4
9.97
14.2
23.9
10.8
22.8
56.3
24.2
MLLMCLIP (Ours)
LLaVA-1.6-Mistral-7B
48.2
65.0
32.1
13.8
19.0
14.8
8.4
10.8
15.4
33.2
10.2
24.4
66.6
27.8
Table 3: Zero-shot classification performance on 13 classification datasets.
Image–to–text retrieval
Text–to–image retrieval
MSCOCO
Flickr-30K
MSCOCO
Flickr-30K
Method
External Source
R@1
R@5
R@10
R@1
R@5
R@10
R@1
R@5
R@10
R@1
R@5
R@10
CLIP
–
9.02
24.3
33.7
18.3
39.9
50.4
6.85
18.7
27.1
12.9
31.6
41.5
LaCLIP
LLAMA-7B
9.80
24.8
33.7
20.8
40.4
51.5
6.72
19.1
27.8
15.9
36.8
47.8
NegCLIP
Qwen3-4B
9.38
24.4
34.4
20.1
42.8
53.6
7.66
20.0
28.5
13.7
32.2
42.7
FSC-CLIP
Qwen3-4B
11.4
27.8
37.7
22.0
46.7
58.0
8.91
23.5
32.8
17.4
38.4
49.0
Table 4: Zero-shot retrieval performance on MSCOCO and Flickr-30K datasets.
Image Teacher
Text Teacher
Comp.
Zero-shot Cls.
Ret.
None
None
37.1
21.2
11.8
[Image End]
None
37.5
25.2
16.2
[Text End]
None
38.0
26.6
17.8
[Text End]
[Text End]
38.2
28.1
17.8
Attention-weighted pooling
40.2
31.1
18.9
Top- k multi-token pooling ( k=8 )
39.7
30.8
18.2
Table 5: Effect of teacher token selection and per-layer aggregation. [Image End] and [Text End] denote the token positions at the end of the image segment and of the full multimodal sequence. The lower block varies how many attention-selected tokens are kept per layer.
Type
Loss
Comp.
Zero-shot Cls.
Ret.
Direct
MSE
30.2
7.00
0.05
Cosine
38.6
27.5
17.2
KL Div.
38.2
28.1
18.4
JS Div.
37.4
25.8
16.0
Relational
CKA
40.0
31.3
19.1
Table 6: Effect of different distillation loss functions on downstream performance.
Data
Feature
Text gen. (s)
0.278±0.001
–
Image gen. (s)
0.557±0.012
–
Feature ext. (s)
–
0.232±0.005
Total (s)
0.835±0.012
0.232±0.005
Table 7: Per-batch preprocessing time at batch size 32, comparing data synthesis against feature extraction. Mean ± std over 5 batches on a single GPU.
Model
#Params (B)
Inf. time (ms)
SugarCrepe
VLM2Vec-v1
2.21
114.60±0.33
64.6
VLM2Vec-v2
2.22
115.92±0.23
72.7
Qwen3-VL-Emb.-2B
2.13
52.36±0.21
83.0
MLLMCLIP
0.15
4.57±0.04
71.3
Table 8: Single-sample inference cost and SugarCrepe accuracy. Mean ± std over 10 runs on a single GPU.
Appendix figures & tables6 assets
Supplementary material from the paper’s appendix.
Appendix
Method
Supervision
Comp.
Zero-shot Cls.
Ret.
NegCLIP
Data
37.9
25.0
12.9
TripletCLIP
Data
38.5
25.6
15.7
MLLMCLIP
Feature
40.0
31.3
19.1
Appendix
Table A: Data-level versus feature-level distillation with the same MLLM (Qwen3.5-2B) supplying both forms of supervision. The baseline rows are controlled reruns, not the main-table rows; TripletCLIP still renders its negative images with SDXL-Turbo.
Teacher Prompt
Comp.
Zero-shot Cls.
Ret.
Plain caption ( {caption} only)
39.6
30.9
18.2
Compositional prompt (ours)
40.0
31.3
19.1
Appendix
Table B: Effect of the prompt used for teacher feature extraction. Both rows share the same Qwen3.5-2B teacher and training settings; only the extraction prompt differs.
Layer Selection
Comp.
Zero-shot Cls.
Ret.
Lower Block (1–12)
38.9
30.1
17.2
Middle Block (13–24)
38.2
28.6
16.3
Upper Block (25–36)
38.7
29.9
16.1
Strided (1,4,7…)
40.0
31.3
19.1
Appendix
Table C: Downstream performance with varying teacher layer selection strategies for distillation.
λ
Comp.
Zero-shot Cls.
Ret.
0.1
38.5
25.3
13.5
1
40.0
31.3
19.1
10
40.2
30.9
18.5
100
37.8
26.3
17.9
Appendix
Table D: Downstream performance with varying weight parameter during pre-training.
Table E: Public sources of the models used in our experiments.
Model
GT-position / Backbone
Replace
Swap
Add
Average
Object
Attribute
Relation
Object
Attribute
Object
Attribute
MLLM-as-Judge models
LLAVA-1.6-mistral-7B
First
99.3
98.0
95.8
89.4
96.2
97.2
93.1
95.6
Second
93.8
82.6
67.6
69.4
77.6
79.3
50.0
74.3
Average
96.5
90.3
81.7
79.4
86.9
88.2
71.5
85.0
LLAVA-1.6-vicuna-7B
First
98.1
96.1
89.6
80.8
89.9
93.9
85.5
90.6
Appendix
Table F: Comparison of MLLM-as-judge models and MLLM-based embedding models on the SugarCrepe benchmark. Judge models are queried twice per example with the ground-truth caption at position A ( First ) and position B ( Second ); embedding models score each caption by image–text similarity and report a single per-task accuracy.
Contrastive Language-Image Pre-training (CLIP) demonstrates strong zero-shot generalization, but due to substantial computational and memory costs, distillation into lightweight models is required. Existing relational objectives do not explicitly model multidirectional relationships between teacher and student embeddings, potentially leaving the geometric relationships insufficiently constrained. This may disrupt the modality-gap structure important for zero-shot transfer. To address these limitations, we propose a relational distillation framework, CLIP-RD, which introduces two relational methods, Vertical Relational Distillation (VRD) and Cross Relational Distillation (XRD). VRD aligns teacher-student intra-modal similarity distributions to enforce consistent distillation strength across image and text embeddings. Meanwhile, XRD aligns the teacher-image-student-text and teacher-text-student-image similarity distributions to impose bidirectional cross-modal symmetry. By jointly modeling these multidirectional relational structures, CLIP-RD aligns the student's embedding geometry more faithfully to the teacher's, outperforming CLIP-KD by 1.8%p. This performance improvement is maintained across diverse architectures, teacher scales, retrieval tasks, downstream tasks, and corruption settings, with negligible additional training-time overhead.
Contrastive Language-Image Pre-training (CLIP) relies on Vision Transformers whose attention mechanism is susceptible to spurious correlations, and scales quadratically with resolution. To address these limitations, We present CLIMP, the first fully Mamba-based contrastive vision-language model that replaces both the vision and text encoders with Mamba. The new architecture encodes sequential structure in both vision and language, with VMamba capturing visual spatial inductive biases, reducing reliance on spurious correlations and producing an embedding space favorable for cross-modal retrieval and out-of-distribution robustness-surpassing OpenAI's CLIP-ViT-B by 7.5% on ImageNet-O. CLIMP naturally supports variable input resolutions without positional encoding interpolation or specialized training, achieving up to 6.6% higher retrieval accuracy at 16x training resolution while using 5x less memory and 1.8x fewer FLOPs. The autoregressive text encoder further overcomes CLIP's fixed context limitation, enabling dense captioning retrieval. Our findings suggest that Mamba exhibits advantageous properties for vision-language learning, making it a compelling alternative to Transformer-based CLIP.The code and models are publicly available at https://github.com/NimrodShabtay/CLIMP}
Vision-language models (VLMs) demonstrate strong performance across compositional reasoning benchmarks, which require reasoning over semantic perturbations of objects, attributes, relations, and their interactions. However, our controlled analysis reveals that existing compositionality-aware VLMs exhibit element-specific biases, often underperforming vanilla CLIP on certain compositional elements. To address this, we propose Compositional Scene Graph-guided CLIP (CS-CLIP), which uses scene graphs to identify compositional elements and construct structured negatives via selective masking. We further retain negatives that are most contradictory to the original caption, forcing the model to rely on compositional structure rather than surface cues. CS-CLIP achieves state-of-the-art compositional reasoning with robust performance across compositional elements. It also preserves general vision-language capabilities such as cross-modal retrieval and downstream visual reasoning, while requiring fewer training samples than prior methods.