核心概念
PRIVIMAGE, a novel method for efficiently generating differentially private synthetic images, leverages semantic-aware pre-training on a carefully selected subset of public data to achieve superior fidelity and utility compared to state-of-the-art approaches.
要約
The paper proposes PRIVIMAGE, a novel method for differentially private synthetic image generation. The key ideas are:
- Semantic Distribution Query:
- Derive a semantic query function from the public dataset to extract the semantic distribution of the sensitive dataset.
- Introduce Gaussian noise to the queried semantic distribution to ensure differential privacy.
- Select data from the public dataset whose semantics align with the high-probability regions of the sensitive semantic distribution.
- Pre-training and Fine-tuning:
- Pre-train an image generative model (GAN or diffusion model) on the selected public dataset.
- Fine-tune the pre-trained model on the sensitive dataset using Differentially Private Stochastic Gradient Descent (DP-SGD).
The authors show that PRIVIMAGE, by utilizing only 1% of the public dataset for pre-training, can significantly outperform state-of-the-art methods in terms of fidelity and utility of the generated synthetic images, while also conserving computational resources. On average, PRIVIMAGE achieves 6.8% lower FID and 13.2% higher Classification Accuracy compared to the state-of-the-art method.
The authors also analyze the factors that contribute to the success of PRIVIMAGE, including the alignment of semantic distributions between the public and sensitive datasets, as well as the benefits of using lightly parameterized models during fine-tuning.
統計
PRIVIMAGE uses only 1% of the ImageNet dataset for pre-training, compared to state-of-the-art methods that use the full ImageNet dataset.
The diffusion model in PRIVIMAGE involves only 7.6% of the parameters used in the state-of-the-art method.
引用
"PRIVIMAGE employs a more compact public dataset for pre-training, which conserves not only computational resources and time but also achieves competitive synthesis performance in terms of both fidelity and utility."
"By utilizing just 1% of the ImageNet dataset for pre-training, we can achieve superior synthesis performance compared to existing solutions that use the full dataset for pre-training."