Multimodal large language models (MLLMs) have achieved strong performance on diverse vision-language tasks, but their computational demands limit deployment under constrained budgets, particularly on edge devices. Many works focus on Knowledge Distillation (KD) and try to transfer knowledge from powerful teacher models to students. In addition to reducing model size, visual token compression provides a complementary route to efficiency, but introduces mismatched visual token counts that complicate direct token-wise knowledge transfer. To mitigate this, we propose DVTR-KD, a knowledge distillation framework based on Dense Visual Token Reconstruction, which reconstructs the teacher's dense visual tokens from the student's compressed tokens. We reconstruct visual states after the final LLM layer and at the input to an intermediate layer identified as important for visual-information readout. At the intermediate layer, reconstruction is supervised through the teacher's response predictions rather than by direct token-wise KL or MSE matching. An auxiliary attention-readout loss complements this response-level supervision by aligning how the student and the original teacher integrate contextual information when predicting responses. Evaluations on diverse benchmarks demonstrate that DVTR-KD improves the performance of token-compressed students while retaining the inference efficiency afforded by visual token compression.
Figures & tables
Figure 1: Layer-wise sensitivity to visual-value ablation after SFT and before distillation. We zero the value vectors of all visual tokens in one transformer layer at a time and report the change in response NLL ( ΔNLL ), averaged over the same diagnostic subset. In the legends, 1× denotes uncompressed models, while 4× and 16× denote models with nominal fourfold and sixteenfold reductions in visual-token count. The sample counts are summed over all training datasets before distillation.
Figure 2: Overview of DVTR-KD. (a) The intermediate reconstructor Rmid reconstructs student visual states in the teacher’s dense layout at PVRL, substituting teacher’s visual states; this reconstruction is supervised through response predictions produced by the teacher from the PVRL onward. Native response distillation and an independent final-layer reconstructor Rlast provide additional supervision. (b) Readout alignment uses attention outputs from the original teacher and the student. (c) An illustration to the reconstructor.
Model
Stage 1
Stage 1.5
SFT
KD
Student
LLaVA-PreTrain-558K
–
LLaVA-NeXT-779K
LLaVA-NeXT-779K
Same-data teacher
LLaVA-PreTrain-558K
–
LLaVA-NeXT-779K
Frozen
Data-rich teacher
LLaVA-PreTrain-558K
LLaVA-ReCap-558K
LLaVA-OneVision-SI-3.3M
Frozen
Table 1: Training data for model preparation and knowledge distillation. “–” indicates a skipped stage; “Frozen” indicates that the teacher is used without parameter updates during KD.
General
Knowledge
OCR
Method
ρ2
GQA
MME
RWQA
SQA
AI2D
MMMU
MMStar
ChartQA
DocVQA
TextVQA
OCRBench
Avg11
Qwen3-0.6B teacher trained on 4.4M samples → Qwen3-0.6B compressed students
Teacher
1×
56.6
1862.9
61.7
88.2
73.6
37.0
50.2
78.8
87.5
77.3
74.3
68.3
SFT
4×
57.8
1450.2
53.6
59.8
59.9
32.1
38.3
64.6
67.7
63.1
49.8
54.4
MiniLLM
4×
58.3
1616.3
56.1
61.3
60.8
32.1
38.6
64.6
66.9
65.1
52.2
55.8
LLaVA-KD ∗
4×
59.7
1636.3
58.0
62.6
64.9
32.3
40.5
70.6
74.4
68.0
56.3
58.7
Table 2: Distillation results across visual-token compression ratios, teacher data regimes and teacher scales. All methods are re-implemented for fair comparison and start from the corresponding SFT model. ρ2 denotes the nominal visual-token compression factor. LLaVA-KD ∗ means we use our reconstruction method to align different visual-token counts after last block. MME scores are divided by 28 when calculating the average scores. Avg11 is the mean over all 11 benchmarks.
Lresp
Lvis
LDVTR
Lreadout
Avg11
✓
–
–
–
51.0
✓
✓
–
–
51.2
✓
✓
✓
–
52.6
✓
✓
✓
✓
53.0
Table 3: Ablation study on contributions from key components in our method.
ρ2
type
Avg11
4×
MSE
60.2
4×
response
59.9
16×
MSE
51.9
16×
response
53.0
Table 4: Ablation study on supervision type for reconstruction at PVRL.
ℓ
AvgG
AvgK
AvgO
Avg11
1
55.5
49.7
51.6
52.0
11
56.6
50.8
51.6
52.7
13
55.9
50.5
52.3
52.6
12 ( ℓ∗ )
56.6
51.0
52.4
53.0
Table 5: Reconstruction at different layers. AvgG , AvgK , and AvgO denote the mean scores on the General, Knowledge, and OCR benchmarks, respectively.
Appendix figures & tables4 assets
Supplementary material from the paper’s appendix.
Appendix
Hyperparameter
Stage-1
Stage-1.5
Stage-2
KD
Train ViT Backbone
–
–
–
–
Train Projector
✓
✓
✓
✓
Train Compressor
✓
–
✓
✓
Train LLM
–
✓
✓
✓
Train Reconstructor
–
–
–
✓
Projector LR
10−3
2×10−5
2×10−5
2×10−5
Appendix
Table 6: Training hyperparameters across different stages.
Benchmark
Split
Count
Metric
GQA
Test-dev balanced
12,578
Exact match
MME
Test
2,374
Acc. + Acc. +
RWQA
Test
765
Accuracy
SQA
Test (image subset)
2,017
Accuracy
AI2D
Test
3,088
Accuracy
MMMU
Validation
900
Accuracy
Appendix
Table 7: Evaluation splits and metrics. Counts denote evaluated questions.
Lresp
Lvis
Lrel
Avg11
✓
–
–
51.0
✓
✓
–
51.2
✓
✓
✓
50.6
Appendix
Table 8: Effect of relation distillation in our adapted LLaVA-KD baseline under ρ2=16 .
Figure 3: Layer-wise sensitivity to visual-value ablation after distillation. We compare DVTR-KD students with the data-rich teacher and the corresponding SFT students.