Do We Need All the Synthetic Data? Targeted Image Augmentation via Diffusion Models

ICLR 2026 Conference Submission13941 Authors

18 Sept 2025 (modified: 08 Oct 2025)ICLR 2026 Conference SubmissionEveryoneRevisionsBibTeXCC BY 4.0
Keywords: Synthetic data generation, Image augmentation, Diffusion models
TL;DR: We propose a novel targeted image augmentation method using synthetic images from diffusion models
Abstract: Synthetically augmenting training datasets with diffusion models has been an effective strategy for improving generalization of image classifiers. However, existing techniques struggle to ensure the diversity of generation and increase the size of the data by up to 10-30x to improve the in-distribution performance. In this work, we show that synthetically augmenting part of the data that is not learned early in training with faithful images—containing same features but different noise—outperforms augmenting the entire dataset. By analyzing a two-layer CNN, we prove that this strategy improves generalization by promoting homogeneity in feature learning speed without amplifying noise. Our extensive experiments show that by augmenting only 30%-40% of the data, our method boosts generalization by up to 2.8% in a variety of scenarios, including training ResNet, ViT, ConvNeXt, and Swin Transformer on CIFAR-10/100, and TinyImageNet, with various optimizers including SGD and SAM. Notably, our method applied with SGD outperforms the SOTA optimizer, SAM, on CIFAR-100 and TinyImageNet.
Supplementary Material: zip
Primary Area: other topics in machine learning (i.e., none of the above)
Submission Number: 13941
Loading