Large Multimodal Models (LMMs) struggle to adapt varying computational budgets due to numerous visual tokens. Previous methods attempted to reduce the number of visual tokens before or within LLMs. However, these strategies inevitably result in the loss of visual semantic. To address these issues, we introduce FMVR, a plug-and-play and extremely simple Frequency-Modulated Visual Restoration strategy to boost the reasoning ability of LMMs under visual token reduction. Specifically, FMVR disentangles the visual representation of fewer visual tokens into low- and high-frequency components through AvgPool and MaxPool. The derived frequencies are subsequently modulated using lightweight learnable parameters. The high-frequency from AvgPool acts as a saliency filter to enhance saliency visual semantics, while the low-frequency from MaxPool acts as an anti-saliency filter to strengthen weak visual semantics. It enables the preservation of visual semantics dominated by few visual tokens and the restoration of diluted visual semantics. Additionally, we inject FMVR into Matryoshka Representation Learning to learn coarse-to-fine visual token sets, thus enabling to elastically adjust the number of visual tokens during inference while maintaining comparable performance. Experiments across 10 image-based and 4 video-based bench marks demonstrate that FMVR-LLaVA reduce the FLOPs of LLaVA-1.5-7B by 89%, while maintaining almost 100% of the original accuracy. The code will be open.
Figures & tables
Figure 1: Our FMVR (b) can restore the visual semantics from compressed tokens, alleviating the loss of visual contents in previous token compression methods (a).
Figure 2: Grad-CAM visualization (576 and 36 visual tokens) shows that the reduction of visual tokens leads to a noticeable degradation in visual focus.
Figure 3: Illustration of FMVR-LLaVA. The FMVR is injected into MRL to construct nested visual tokens, where FMVR is used to enhance the visual semantics of each visual token set, thus forming a set of reinforced nested visual tokens for LLM training.
Methods
#Vision Tokens
VQAv2
GQA
VisWiz
SQA IMG
VQA Text
POPE
MME
MMB EN
MMB CN
MMVet
Avg. (%)
BLIP-2 [ 37 ]
32
65.0
41.0
19.6
61.0
42.5
85.3
1293.8
31.2
–
22.4
–
InstructBLIP [ 19 ]
32
72.4
49.2
34.5
60.5
50.1
86.1
1391.4
36.0
23.7
26.2
50.8
IDEFICS-9B [ 28 ]
64
50.9
38.4
35.5
53.5
25.9
81.9
1177.3
48.2
–
30.0
–
IDEFICS-80B [ 28 ]
64
60.0
45.2
36.0
61.8
30.9
66.0
1518.2
54.5
–
39.7
–
Qwen-VL [ 4 ]
256
78.8
59.3
35.2
67.1
63.8
70.0
1487.6
38.2
7.4
13.0
50.7
Qwen-VL-Chat [ 4 ]
256
78.2
57.5
38.9
68.2
60.7
74.9
1487.5
60.6
–
47.3
–
Table 1: Performance comparison on LLaVA-1.5-7B across 10 image-based benchmarks. ‘#VisionTokens’ is the number of vision tokens. Δ rows show the change vs. LLaVA baseline.
Method
VQAv2
GQA
VisWiz
SQA IMG
VQA Text
POPE
MME
MMB EN
MMB CN
MMVet
Avg.(%)
M3 (Baseline)
78.5
61.3
53.1
65.2
54.8
87.0
1451.5
66.4
56.3
30.2
62.5
FMVR (Ours)
78.6
62.3
55.1
69.7
55.5
86.4
1473.9
65.8
57.6
33.4
63.8
FMVR w/o AvgPool
77.9
62.0
54.6
68.1
54.3
85.7
1459.6
65.4
56.7
32.5
63.0
FMVR w/o MaxPool
78.3
62.6
53.3
68.4
55.0
86.9
1463.7
65.8
57.1
32.6
63.3
Table 2: Ablation study of applying different pooling unit in FMVR.
Methods
Tokens
FLOPs (TB)
Prefill Time (ms)
Total Memory (GB)
Avg (%)
LLaVA-v1.5
576
8.0
58.1
21.6
63.0
FMVR
144
2.2 (×3.6)
19.5 (×3.0)
15.0 (×1.4)
63.8
36
0.9 (×8.9)
18.0 (×3.2)
13.8 (×1.6)
62.9
9
0.5 (×16)
17.7 (×3.3)
13.6 (×1.6)
61.1
1
0.4 (×20)
17.6 (×3.3)
13.5 (×1.6)
57.7
Table 3: Efficiency analysis of different numbers of vision tokens on LLaVA-1.5-7B.
Methods
Vision Encoder
Projection
FMVR
LLM
Total
LLaVA-v1.5
0.349
0.024
-
8.0
8.37
FMVR 576
0.349
0.024
6.4e-5
8.0
8.37
Table 4: FLOPs of each component in FMVR-LLaVA.
Methods
Tokens
FLOPs (TB)
Prefill Time (ms)
Avg (%)
FastV
192
2.1
34.1
55.9
PDrop
192
2.0
36.7
61.6
SparseVLM
192
2.1
36.5
61.2
FMVR
36
0.9
18.0
62.9
Table 5: Efficiency analysis of different pruning methods on LLaVA-1.5-7B.
Methods
#Vision Tokens
VQAv2
GQA
VisWiz
SQA IMG
VQA Text
POPE
MME
MMB EN
MMB CN
MMVet
Avg. (%)
LLaVA-NeXT-7B [ 46 ]
2880
81.3
62.5
55.2
67.5
60.3
86.8
1511.8
65.8
57.3
40.0
65.2
FastV [ 11 ]
320
61.5
49.8
51.3
66.6
52.2
49.5
1099.0
53.4
42.5
20.0
50.2
PyramidDrop [ 69 ]
320
66.8
50.4
49.7
66.7
49.0
60.8
1171.5
55.5
44.7
24.0
52.6
SparseVLM [ 83 ]
320
74.6
57.9
54.2
67.2
56.5
76.9
1386.1
63.1
56.7
32.8
60.9
Prumerge+ [ 60 ]
320
75.3
58.8
57.7
68.1
54.0
79.5
1444.3
63.0
55.6
31.4
61.6
TRIM [ 63 ]
320
74.9
59.9
53.5
66.2
50.2
86.5
1443.8
63.5
51.0
32.7
61.1
Table 6: Performance comparison on LLaVA-NeXT-7B across 10 image-based benchmarks. ‘#VisionTokens’ is the number of vision tokens. Δ rows show the change vs. LLaVA-NeXT-7B baseline.
Methods
#Vision Tokens
Video-based Question-Answer
Video-based Generative Performance
MSVD
MSRVTT
ActivityNet
Avg.
Correct.
Detail
Context.
Temp.
Consist.
Avg.
LLaMA Adapter [ 82 ]
1280
54.9
43.8
34.2
44.3
2.03
2.32
2.30
1.98
2.15
2.16
VideoChat [ 39 ]
512
56.3
45.0
26.5
42.6
2.23
2.50
2.53
1.94
2.24
2.29
Video-LLAMA [ 77 ]
1024
51.6
29.6
12.4
31.2
1.96
2.18
2.16
1.82
1.79
1.98
Video-ChatGPT [ 39 ]
∼ 360
64.9
49.3
35.2
49.8
2.40
2.52
2.62
1.98
2.37
2.38
BT-Adapter [ 49 ]
∼ 260
67.5
57.0
45.7
56.7
2.68
2.69
3.27
2.34
2.46
2.69
Table 7: Performance comparison on LLaVA-NeXT-7B across 4 video-based benchmarks. ‘#VisionTokens’ is the number of vision tokens. Δ rows show the change vs. LLaVA-NeXT-7B baseline.
Figure 4: Comparison under different numbers of vision tokens. Our method achieves higher accuracy than M3 and MQT-LLaVA.
Figure 5: Grad-CAM visualization and response comparison between w/o FMVR and w FMVR under 36 visual tokens. From Grad-CAM visualization, the reduction of visual tokens leads to a noticeable degradation in visual semantics, which leads to hallucinations of certain objects in the response.
Figure 6: Case of image understanding on different VQA prompts. Our method yields basically correct answers under different numbers of visual tokens.
Appendix figures & tables5 assets
Supplementary material from the paper’s appendix.
Appendix
Methods
#Vision Tokens
TextVQA
ChartQA
AI2D
MMB EN
Avg. (%)
Qwen2.5-VL
1296
84.8
86.1
80.4
82.8
83.5
FastV
128
73.8
52.2
71.4
72.9
67.6
DivPrune
128
67.0
50.4
72.1
77.8
66.8
CDPruner
128
77.8
59.2
74.0
76.2
71.8
FMVR (Ours)
81
76.3
62.2
77.5
79.6
73.9
Appendix
Table 8: Performance comparison of different pruning methods on Qwen2.5-VL-7B.
Methods
#Vision Tokens
VQAv2
GQA
VisWiz
SQA IMG
VQA Text
POPE
MME
MMB EN
MMB CN
MMVet
Avg. (%)
LLaVA-1.5-13B [ 48 ]
576
80.0
63.3
53.6
72.8
61.2
86.0
1531.2
68.5
63.5
36.2
66.2
FastV [ 11 ]
128
75.3
58.3
54.6
74.2
58.6
75.5
1460.6
66.1
62.3
32.8
63.1
PyramidDrop [ 69 ]
128
78.2
61.0
53.8
73.3
60.2
83.6
1489.5
67.5
62.8
32.1
64.7
SparseVLM [ 83 ]
128
77.6
59.6
51.4
74.3
59.3
85.0
1487.9
68.4
62.6
35.2
64.8
Prumerge+ [ 60 ]
128
76.2
58.3
52.8
73.3
56.1
82.7
1445.9
66.3
61.2
33.6
63.3
TRIM [ 63 ]
128
76.4
59.4
49.7
72.4
55.0
86.8
1426.9
67.1
58.4
35.1
63.2
Appendix
Table 9: Performance comparison on LLaVA-1.5-13B across 10 image-based benchmarks. ‘#VisionTokens’ is the number of vision tokens. Δ rows show the change vs. LLaVA-v1.5-13B.
Num of Vis Tokens
TextVQA
MMBench
Avg Pooling
Sequential
Spatial
Max Pooling
Avg Pooling
Sequential
Spatial
Max Pooling
1
49.2
46.3
45.9
47.1
60.7
57.9
58.6
59.8
9
50.8
46.7
46.4
48.2
64.2
60.4
61.5
63.9
36
55.3
51.2
49.0
52.8
65.2
61.8
63.1
64.5
144
55.5
53.7
50.6
53.3
65.8
64.2
63.7
64.9
576
57.8
55.6
52.6
54.7
65.9
64.7
64.0
65.3
Appendix
Table 10: Ablation study on Matryoshka visual token sampling, including average pooling, sequential sampling, spatial sampling, and max pooling.
Tokens
Method
VQAv2
GQA
VisWiz
SQA IMG
VQA Text
POPE
MME
MMB EN
MMB CN
MMVet
576
baseline
78.5
62.0
50.0
66.8
58.2
85.9
1510.7
64.3
58.3
30.5
Ours
79.2
63.0
56.5
68.9
57.8
87.5
1510.1
65.9
58.0
34.3
144
baseline
77.8
61.1
48.3
67.5
57.3
85.0
1480.4
65.1
57.1
30.2
Ours
78.6
62.3
55.1
69.7
55.5
86.4
1473.9
65.8
57.6
33.4
36
baseline
76.1
58.4
46.8
67.0
56.7
85.2
1448.3
64.5
57.7
29.4
Ours
76.5
60.9
52.9
69.5
55.3
85.9
1452.5
65.2
58.3
32.2
Appendix
Table 11: Baseline results of token numbers on LLaVA-1.5-7B.
Figure 7: Example demonstrating FMVR’s image understanding capability on more challenging OCR task. Response marked in red indicates errors.
School of Future Technology, Dalian University of Technology, Dalian 116024, China · S-Lab, Nanyang Technological University, Singapore 639798 · OPPO Research Institute, Shenzhen 518000, China +1