puzzlemix
**PuzzleMix** is a **data augmentation technique that optimizes the mixing mask to maximize the saliency (importance) of the mixed regions** — cutting and mixing the most informative regions from each training image, guided by the model's gradient-based saliency maps.
**How Does PuzzleMix Work?**
- **Saliency**: Compute gradient-based saliency maps for both images.
- **Optimal Transport**: Find the mixing mask that maximizes the total saliency of visible regions.
- **Mix**: Apply the optimized mask to create a training sample with the most useful features from both images.
- **Labels**: Mixed proportionally to the visible saliency-weighted area.
- **Paper**: Kim et al. (2020).
**Why It Matters**
- **Intelligent Mixing**: Unlike random CutMix, PuzzleMix ensures informative regions are visible, not occluded.
- **Accuracy**: Consistently outperforms CutMix and Mixup by 0.5-1.0% on ImageNet.
- **Saliency-Guided**: Uses the model's own understanding to create maximally informative training samples.
**PuzzleMix** is **CutMix with intelligence** — using saliency maps to mix the most important parts of each image together.