GMAIL: Generative Modality Alignment for generated Image Learning
Authors: Shentong Mo, Sukmin Yun
Organizations: Department of Machine Learning, CMU, USA · Department of Machine Learning, MBZUAI, UAE · Department of Artificial Intelligence, Hanyang University ERICA, South Korea
Generative models have made it possible to synthesize highly realistic images, potentially providing an abundant data source for training machine learning models. Despite the advantages of these synthesizable data sources, the indiscriminate use of generated images as real images for training can even cause mode collapse due to modality discrepancies between real and synthetic domains. In this paper, we propose a novel framework for discriminative use of generated images, coined GMAIL, that explicitly treats generated images as a separate modality from real images. Instead of indiscriminately replacing real images with generated ones in the pixel space, our approach bridges the two distinct modalities in the same latent space through a multi-modal learning approach. To be specific, we first fine-tune a model exclusively on generated images using a cross-modality alignment loss and then employ this aligned model to further train various vision-language models with generated images. By aligning the two modalities, our approach effectively leverages the benefits of recent advances in generative models, thereby boosting the effectiveness of generated image learning across a range of vision-language tasks. Our framework can be easily incorporated with various vision-language models, and we demonstrate its efficacy throughout extensive experiments. For example, our framework significantly improves performance on image captioning, zero-shot image retrieval, zero-shot image classification, and long caption retrieval tasks. It also shows positive generated data scaling trends and notable enhancements in the captioning performance of the large multimodal model, LLaVA.
Figures & tables
Figure 1: Illustration of the proposed framework for vision-language tuning with Gen-Real alignment from diffusion models. We propose a method that explicitly aligns a CLIP trained on real images with another CLIP model trained on generated images and then leverages the aligned CLIP to train state-of-the-art vision-language models on generated images ( i.e., Gen-CLIP Flow). For inference with real images, the original CLIP is used to process real images, thereby avoiding discrepancies between real and generated modalities.
Method
B@4 (↑)
METEOR(↑)
CIDEr (↑)
SPICE (↑)
ROUGE-L (↑)
WMD (↑)
ClipCap ( Mokady et al., 2021 )
32.15
27.10
108.35
20.12
–
–
ClipCap + GMAIL (ours)
38.12
31.67
119.53
23.75
56.27
62.16
IFCap ( Lee et al., 2024 )
33.25
28.60
115.27
21.58
51.35
56.72
IFCap + GAMIL (ours)
39.32
32.07
127.86
23.98
59.83
63.51
LLaVA ( Liu et al., 2023 )
39.67
32.38
134.29
24.17
61.36
65.78
LLaVA + GMAIL (ours)
43.26
34.89
146.38
27.23
65.25
71.39
Table 1: Image captioning. We perform fine-tuning on pre-trained ClipCap, IFCap, LLaVA, and LLaMA-3 for image captioning on COCO. We report the standard metrics to evaluate the quality of generated captions. The best results are indicated in bold .
Method
Image-to-Text
Text-to-Image
R@1 (↑)
R@5 (↑)
R@10 (↑)
R@1 (↑)
R@5 (↑)
R@10 (↑)
CLIP ( Radford et al., 2021 )
51.8
76.8
84.3
32.7
57.7
68.2
CLIP + GMAIL (ours)
56.8
80.1
87.2
37.5
62.7
73.2
Long-CLIP ( Zhang et al., 2024 )
57.2
80.8
87.8
40.4
65.9
75.7
Long-CLIP + GMAIL (ours)
62.3
84.1
91.2
45.6
69.8
79.5
Table 2: Zero-shot image retrieval on COCO. We perform zero-shot retrieval on pre-trained CLIP models for image retrieval on the COCO benchmark. We report the image-to-text and text-to-image Recall@1,5,10 metrics to evaluate the quality of retrieved images.
Method
Image-to-Text
Text-to-Image
R@1 (↑)
R@5 (↑)
R@10 (↑)
R@1 (↑)
R@5 (↑)
R@10 (↑)
CLIP ( Radford et al., 2021 )
44.1
68.2
77.0
24.7
45.1
54.6
CLIP + GMAIL (ours)
47.1
71.2
79.6
30.2
50.3
60.5
Long-CLIP ( Zhang et al., 2024 )
47.2
71.5
80.0
33.1
55.6
64.9
Long-CLIP + GMAIL (ours)
51.6
75.3
83.6
39.3
61.5
71.8
Table 3: Zero-shot image retrieval on Flickr30k. We perform zero-shot retrieval on pre-trained CLIP models for image retrieval on the Flickr30k benchmark. We report the image-to-text and text-to-image Recall@1,5,10 metrics to evaluate the quality of retrieved images.
Method
DTD
Stanford Cars
SUN397
Food 101
Aircraft
Oxford Pets
Caltech 101
ImageNet
CLIP ( Radford et al., 2021 )
55.20
77.53
69.31
93.08
32.88
93.33
93.24
75.54
CLIP + GMAIL (ours)
65.26
81.32
75.53
95.21
37.85
95.23
95.57
77.68
SynCLR ( Tian et al., 2024 )
79.90
93.80
76.20
91.60
81.70
93.60
95.30
85.80 (ft)
SynCLR + GMAIL (ours)
83.67
96.56
81.25
96.38
86.75
95.70
98.35
87.95 (ft)
Table 4: Zero-shot image classification. We perform a zero-shot evaluation on pre-trained CLIP models for image classification on eight benchmarks. We report the top-1 accuracy to evaluate the quality of learned representations. The best results are indicated in bold .
Method
Image-to-Text
Text-to-Image
CLIP ( Radford et al., 2021 )
78.2
79.6
CLIP + GMAIL (ours)
85.2
86.7
Long-CLIP ( Zhang et al., 2024 )
94.6
93.3
Long-CLIP + GMAIL (ours)
97.2
96.1
Table 5: Long caption retrieval on ShareGPT4V. We report the image-to-text and text-to-image Recall@1 to evaluate the quality of retrieved images. The best results are indicated in bold .
Alignment
B@4 (↑)
METEOR(↑)
CIDEr (↑)
SPICE (↑)
ROUGE-L (↑)
WMD (↑)
✗
36.15
30.32
115.35
22.95
55.12
61.08
✓
38.12
31.67
119.53
23.75
56.27
62.16
Table 6: Ablation study on Gen-Real Alignment. We perform ablation studies on image captioning from pre-trained CLIP on generated images. The best results are indicated in bold .
Train Data
Image-to-Text
Text-to-Image
R@1 (↑)
R@5 (↑)
R@10 (↑)
R@1 (↑)
R@5 (↑)
R@10 (↑)
COCO
47.1
71.2
79.6
30.2
50.3
60.5
CC3M
48.6
73.6
82.2
32.6
52.6
62.3
CC12M
50.9
75.3
84.6
34.9
54.7
64.8
Table 7: Scaling trend of Gen-Real alignment on zero-shot image retrieval on Flickr30k. We perform zero-shot retrieval on models trained from COCO, CC3M, and CC12M on Flickr30k. We report the Recall@1,5,10 metrics to evaluate the quality of retrieved images.
Figure 2: Visualizations of real (Column 1) and generated images (Columns 2-6) using the same caption. Those generated images generally capture high-level semantics in real images.
Method
B@4 (↑)
CIDEr (↑)
SigLIP
37.51
117.82
SigLIP + GMAIL (ours)
42.35
125.68
Table 8: Comparison with SigLIP on COCO captioning. Our GMAIL significantly improves SigLIP by effectively addressing the synthetic-real discrepancy. The best results are bold .
Dual Projection
Alignment
Fine-tuning Data
B@4 (↑)
CIDEr (↑)
SPICE (↑)
✗
✗
✗
32.15
108.35
20.12
✗
✗
Synthetic
36.15
115.35
22.95
✓
✓
Synthetic
38.12
119.53
23.75
✗
✗
Real
38.24
119.78
23.86
✓
✓
Real
38.37
119.95
23.98
Table 9: Comparison with models trained on real images. We perform experiments on image captioning from pre-trained CLIP on generated and real images. The best results are indicated in bold .
Method
Accuracy (%)
LLaVA
85.2
LLaVA + GMAIL (ours)
87.6
LLaMA-3
88.5
LLaMA-3 + GMAIL (ours)
91.2
Table 10: Visual question answering on ScienceQA. We report the average accuracy on questions with the image context from the ScienceQA benchmark. The best results are bold .
Method
B@4 (↑)
CIDEr (↑)
SPICE (↑)
LoRA (rank = 2)
36.85
117.62
23.10
LoRA (rank = 4)
38.12
119.53
23.75
LoRA (rank = 6)
37.96
119.12
23.60
Full fine-tuning
37.50
118.95
23.50
Table 11: Ablation study on LoRA rank and full fine-tuning. We perform experiments on image captioning from pre-trained CLIP on generated images. The best results are indicated in bold .
Algorithm 1 GMAIL Algorithm: Training and Inference on Generated and Real Images
Dual Projection
Alignment
Synthetic
Training
Training
Memory
FLOPs
Data
Time (hrs)
Steps
Usage (GB)
(G)
✗
✗
✗
8
50k
24
70.2
✗
✗
✓
12
70k
26
85.5
✓
✓
✓
10
60k
28
85.5
Appendix
Table 12: Computational costs comparisons on COCO training. Our GMAIL introduces a slight increase in memory usage but remains more efficient on the convergence training time and steps than the baseline of indiscriminate mixing (gen+real) without alignment.
Dual Projection
Alignment
Synthetic Data
B@4 (↑)
CIDEr (↑)
SPICE (↑)
✗
✗
✗
32.15
108.35
20.12
✗
✗
✓
35.76
113.42
22.63
✓
✓
✓
37.92
117.6
23.42
Appendix
Table 13: Comparison with the same training steps. We compare CLIP trained on real images, fine-tuned CLIP on generated images without alignment, and ours under COCO training with the same training steps. The best results are indicated in bold .
Alignment
Cosine Similarity (↑)
✗
0.52
✓
0.89
Appendix
Table 14: Quantitative similarity metrics comparisons on COCO. We computed the cosine similarity between paired real and generated image embeddings without and with alignment on COCO dataset.
Method
Accuracy (%)
LLaVA
44.7
LLaVA + GMAIL (ours)
48.3
Appendix
Table 15: Multi-modal reasoning and visual-language alignment on MMMU. We evaluated GMAIL’s performance on MMMU benchmark when integrated with LLaVA. We report the average accuracy on questions with the image context. The best results are bold .
Method
B@4 (↑)
CIDEr (↑)
SPICE (↑)
Task2Sim
36.65
115.72
23.02
GMAIL (ours)
38.12
119.53
23.75
Appendix
Table 16: Comparison to Task2Sim. We report a comparison to Task2Sim ( Mishra et al., 2022 ) , which introduced a mixed training approach (joint usage of real and synthetic data). The best results are indicated in bold .
Method
B@4 (↑)
CIDEr (↑)
SPICE (↑)
FLUX (without alignment)
37.20
117.82
23.40
FLUX + GMAIL (ours)
39.54
122.36
24.15
Appendix
Table 17: Image generation with FLUX. We replace a generative model from Stable Diffusion v2 to FLUX and perform experiments on the image captioning task. The best results are indicated in bold .
Figure 3: Qualitative Visualizations of embeddings of real and synthetic images without (Left) and with (Right) alignment. Blue and red dots denote the embeddings for real and synthetic images, respectively. Our GMAIL with alignment significantly reduced the gap between real and synthetic images, with both modalities aligning closely in the latent space.
Figure 4: Visualizations of real (Column 1) and generated images (Columns 2-6) using the same caption. Those generated images generally capture high-level semantics in real images.
Figure 5: Visualizations of real (Column 1) and generated images (Columns 2-6) using the same caption. Those generated images generally capture high-level semantics in real images.
Figure 6: Visualizations of real (Column 1) and generated images (Columns 2-6) using the same caption. Those generated images generally capture high-level semantics in real images.
Figure 7: Visualizations of real (Column 1) and generated images (Columns 2-6) using the same caption. Those generated images generally capture high-level semantics in real images.
Figure 8: Visualizations of real (Column 1) and generated images (Columns 2-6) using the same caption. Those generated images generally capture high-level semantics in real images.
Figure 9: Visualizations of real (Column 1) and generated images (Columns 2-6) using the same caption. Those generated images generally capture high-level semantics in real images.
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