Organizations: Shanghai Jiao Tong University, China · Xi’an Jiaotong University, China · Shandong University, China · Terminal Intelligent Computing Division, Alibaba Cloud, China · South China University of Technology, China · Jilin University, China
Diffusion models have achieved remarkable success in image and video generation, yet the high computational cost of iterative sampling remains a critical bottleneck for practical deployment. Feature caching has emerged as a promising acceleration paradigm by reusing or predicting intermediate features across timesteps. However, existing training-free methods apply uniform prediction strategies that cannot adapt to the heterogeneous feature dynamics, causing significant quality degradation under high acceleration ratios. We propose LinCa, a feature caching framework based on learnable invertible networks. LinCa decomposes cached features into sub-components with distinct continuity properties via a lightweight invertible network and applies differentiated prediction orders matched to each component. The strict invertibility guarantees lossless reconstruction back to the original feature space, forming a unified Decompose-Predict-Reconstruct pipeline. By training separate predictors for different models and timestep segments, LinCa adapts to heterogeneous feature dynamics. Experiments on FLUX, Qwen-Image, and HunyuanVideo demonstrate that LinCa, with less than 0.2% additional parameters, significantly outperforms existing methods and maintains near-lossless quality at 5-7x speedup. Code: https://github.com/QHR69/LinCa
Figures & tables
Figure 1: Images sampled by Qwen-Image with LinCa at 6.95 × acceleration.
Figure 2: Analysis of dynamics mismatch. (a): Denoise trajectories visualized via Principal Component Analysis (PCA) within FLUX.1-dev and Qwen-Image. Significant continuity differences exist across different models and denoising stages. (b)-(c): Denoise trajectories of specific dimensions visualized via PCA within FLUX.1-dev and Qwen-Image. Even within the same model and stage, significant continuity differences still exist across different feature dimensions. (b) shows dimensions with low continuity and abrupt mutations, while (c) shows dimensions with high continuity and stability.
Figure 3: Overview of the LinCa framework. (a) Feature Caching via LinCa: Feature caching caches features during computation steps and skips computation by utilizing historical cached features during prediction steps, where LinCa provides an end-to-end “Decompose-Predict-Reconstruct” pipeline. (b) LinCa Pipeline: Cached features are decomposed into sub-components with distinct continuity, predicted by differentiated order polynomial extrapolation, and losslessly reconstructed back to the original feature space. (c) Invertible Projection: Each invertible block consists of an invertible 1×1 convolution and an additive coupling layer with lightweight MLPs F and G . The strict invertibility of each sub-layer guarantees lossless reconstruction.
Method
Acceleration
ImageReward ↑
CLIP Score ↑
Latency(s) ↓
Speed ↑
FLOPs(T) ↓
Speed ↑
Original: 50 steps
23.10
1.00 ×
3719.50
1.00 ×
0.9930 ( + 0.0%)
32.61 ( + 0.0%)
60% steps
14.87
1.55 ×
2231.70
1.67 ×
0.9693 ( − 2.4%)
32.50 ( − 0.3%)
Δ− DiT ( N=2 ) [ 7 ]
15.96
1.45 ×
2480.01
1.50 ×
0.9471 ( − 4.6%)
32.46 ( − 0.5%)
Δ− DiT ( N=3 ) [ 7 ]
11.63
1.98 ×
1686.76
2.21 ×
0.8750 ( − 11.9%)
32.29 ( − 1.0%)
FORA (N=3) [ 41 ]
9.08
2.54 ×
1320.07
2.82 ×
0.9802 ( − 1.3%)
32.45 ( − 0.5%)
Table 1: Quantitative comparison of text-to-image generation for FLUX.1-dev. Best results are highlighted in bold , and second-best are underlined .
Figure 4: On FLUX.1-dev, LinCa delivers higher speedup with better text consistency, fine-grained details, and spatial relationships.
Method
Acceleration
Quality Metrics
Perceptual Metrics
Latency(s) ↓
Speed ↑
FLOPs(T) ↓
Speed ↑
ImageReward ↑
CLIP ↑
PSNR ↑
SSIM ↑
LPIPS ↓
Original: 50 steps
126.60
1.00 ×
12917.56
1.00 ×
1.2532 ( + 0.0%)
35.52
∞
1.00
0.00
50% steps
63.62
1.99 ×
6458.78
2.00 ×
1.2023 ( − 4.1%)
35.24
30.55
0.75
0.27
20% steps
25.89
4.89 ×
2583.51
5.00 ×
0.9223 ( − 26.4%)
34.94
28.60
0.60
0.52
TaylorSeer ( N =3) [ 25 ]
62.36
2.03 ×
4646.60
2.78 ×
1.0674 ( − 14.8%)
34.78
28.14
0.53
0.65
HyCa ( N =3) [ 55 ]
59.72
2.12 ×
4646.60
2.78 ×
1.2316 ( − 1.7%)
35.01
30.21
0.80
0.25
Table 2: Quantitative comparison of text-to-image generation for Qwen-Image. Best results are highlighted in bold , and second-best are underlined .
Figure 5: On Qwen-Image, LinCa retains superior image quality and details as the acceleration ratio increases, while Taylorseer degrades with blurring and detail loss.
Method
Efficient
Acceleration
VBench ↑
Attention
Latency(s) ↓
Speed ↑
FLOPs(T) ↓
Speed ↑
Score(%)
Original: 50 steps
✔
185.00
1.00 ×
29773.0
1.00 ×
80.66 ( + 0.0%)
22% steps
✔
40.66
4.55 ×
6550.1
4.55 ×
78.74 ( − 2.4%)
FORA (N=5) [ 41 ]
✔
43.84
4.22 ×
5960.4
5.00 ×
78.83 ( − 2.3%)
ToCa (N=5,R=90%) [ 60 ]
✘
49.07
3.77 ×
7006.2
4.25 ×
78.86 ( − 2.2%)
DuCa (N=5,R=90%) [ 61 ]
✔
40.39
4.58 ×
6483.2
4.48 ×
78.72 ( − 2.4%)
Table 3: Quantitative comparison of text-to-video generation for HunyuanVideo. Best results are highlighted in bold , and second-best are underlined .
Figure 6: On HunyuanVideo, LinCa maintains high-quality generation under higher acceleration ratio, while other methods suffer from lossing background scene, mistaken spatial relationships, and missing motional details.
Method
Acceleration
GEdit-CN (Full)
GEdit-EN (Full)
Latency(s) ↓
Speed ↑
FLOPs(T) ↓
Speed ↑
SC ↑
PQ ↑
OS ↑
SC ↑
PQ ↑
OS ↑
Original: 50 steps
284.51
1.00 ×
28190.88
1.00 ×
7.68
7.51
7.41
7.82
7.54
7.54
50% steps
143.29
1.99 ×
14095.44
2.00 ×
7.70
7.53
7.44
7.77
7.52
7.47
20% steps
58.45
4.87 ×
5638.18
5.00 ×
7.65
7.42
7.35
7.73
7.46
7.44
FORA ( N =5) [ 41 ]
63.15
4.51 ×
5643.13
5.00 ×
7.60
7.31
7.25
7.62
7.34
7.28
DuCa ( N =7, R =95%) [ 61 ]
69.54
4.09 ×
5699.89
4.95 ×
7.73
7.44
7.44
7.80
7.40
7.45
Table 4: Quantitative comparison of image editing for Qwen-Image-Edit. Best results are highlighted in bold , and second-best results are underlined .
Figure 7: On Qwen-Image-Edit, LinCa delivers better prompt comprehension and generates high-fidelity images while maintaining consistency in non-edited regions.
Method
Acceleration
ImageReward ↑
CLIP Score ↑
Latency(s) ↓
Speed ↑
FLOPs(T) ↓
Speed ↑
FLUX.1-lite-8B: 28 steps
8.21
1.00 ×
1291.49
1.00 ×
0.8936 (+0.0%)
32.12 (+0.0%)
LinCa ( N =3): 28 steps
3.34
2.46 ×
556.21
2.32 ×
0.9070 (+1.5%)
32.36 (+0.7%)
FLUX.1-schnell: 4 steps
2.48
1.00 ×
283.56
1.00 ×
0.9692 (+0.0%)
32.54 (+0.0%)
LinCa ( N =3): 4 steps
1.38
1.80 ×
142.16
1.99 ×
0.9843 (+1.6%)
32.67 (+0.4%)
FLUX.1-dev-int8: 50 steps
12.55
1.00 ×
1888.07
1.00 ×
0.9744 (+0.0%)
32.55 (+0.0%)
Table 5: Quantitative comparison of text-to-image generation for FLUX.1-lite-8B, FLUX.1-schnell and FLUX.1-dev-int8.
Figure 8: Ablation results of LinCa. (a)-(b) : Comparison of decomposition network architectures on FLUX.1-dev and Qwen-Image. The learnable invertible network consistently outperforms both MLP and untrained alternatives. (c) Comparison of prediction order strategies. Differentiated multi-order prediction maintains superior quality over single-order prediction.
Appendix figures & tables7 assets
Supplementary material from the paper’s appendix.
Appendix
Figure 9: Prediction error between predicted and ground-truth features. LinCa obtains lower MSE by decomposing features into order-specific subspaces and applying matched prediction orders.
Figure 10: Hyperparameter sensitivity analyses of LinCa. (a) : Impact of timestep segment number S . S=3 yields consistently strong performance, with further increases bringing only marginal gains. (b) : Impact of loss coefficient λ . λ=1 achieves the best performance across most intervals. (c)-(e) : Architecture of the decomposition network. L=2 invertible blocks with hidden dimension h=128 achieves the best performance across all intervals.
Method
Predictor
Speed ↑
ImageReward ↑
CLIP Score ↑
TaylorSeer
Taylor
4.16 ×
0.9793
32.63
LinCa
Hermite
5.51 ×
1.0162
32.72
LinCa
Taylor
5.51 ×
1.0139
32.58
LinCa
Chebyshev
5.51 ×
1.0023
32.60
LinCa
Lagrange
5.51 ×
1.0144
32.60
LinCa
Laguerre
5.51 ×
0.9264
32.50
Appendix
Table 6: Comparison of high-order predictors under similar acceleration ratios.
Method
Steps
Speed ↑
ImageReward ↑
FLUX.1-dev (Original)
50
1.00×
0.99
Comparison with distilled models
FLUX.1-lite-8B
28
1.79×
0.89
LinCa (N=4)
14
3.57×
1.02
Comparison with training-based methods
LESA (N=5)
12
4.17×
1.00
Appendix
Table 7: More results on FLUX.1-dev.
Method
Steps
Speed ↑
ImageReward ↑
Qwen-Image (Original)
50
1.00×
1.25
Comparison with distilled models
Qwen-Image-Distill-Full
15
3.33×
1.02
Qwen-Image-Distill-LoRA
15
3.33×
0.95
LinCa (N=4)
14
3.57×
1.19
Comparison with training-based methods
Appendix
Table 8: More results on Qwen-Image.
Method
Steps
Speed ↑
ImageReward ↑
GenEval ↑
Qwen-Image-Lightning
8
1.00×
1.28
0.84
LinCa (N=3)
4
2.00×
1.26
0.85
Appendix
Table 9: Compatibility with Qwen-Image-Lightning.
Method
Steps
Speed ↑
VBench Score(%) ↑
Wan2.1-1.3B (Original)
50
1.00×
83.72
TaylorSeer (N=5)
12
4.17×
81.07
LinCa (N=6)
10
5.00×
82.56
Appendix
Table 10: Text-to-video generation result on Wan2.1.
Shenzhen Ubiquitous Data Enabling Key Laboratory, Shenzhen International Graduate School, Tsinghua University, Shenzhen, China · Central Media Technology Institute, Huawei Technologies Co., Ltd., Shenzhen, China