Induce to Empower: Improving Lightweight Baselines via Foundation Model Induction for Generalized Polyp Segmentation

Computer Vision and Pattern Recognition

Summary

The authors address the challenge of detecting polyps in colonoscopy images, which is hard because polyps look very different and have fuzzy edges. They note that while big advanced models work well, they are too slow and need lots of data, and small models are fast but less accurate. To fix this, the authors created Lite-Pi, a method that improves small models by combining their strengths with parts of foundation models using special techniques to focus on important polyp features. Tests show Lite-Pi helps small models work better across different datasets without much extra computing, making it useful for real clinical use.

Authors

Shivanshu Agnihotri, Snehashis Majhi, Deepak Ranjan Nayak, Dwarikanath Mahapatra, Debesh Jha

Abstract

Automated polyp segmentation in colonoscopy continues to pose challenges due to substantial appearance variations and indistinct polyp boundaries. Although emerging foundation models (FMs) such as DINOv2, SAM, and OneFormer, demonstrate remarkable generalization capabilities, their direct transfer to the polyp segmentation task and deployment in real-time clinical settings are difficult due to lack of large-scale labeled data and high computational demands. In addition, adopting multiple FMs together raises concerns, even though they encode complementary semantic and structural information. While lightweight models, including U-Net, PraNet and U-Net++, are computationally efficient, they often struggle to generalize across datasets due to limited representational capacity. To address this gap, we propose Lite-Polyp Inductor (Lite-Pi), a novel foundation model induction framework that significantly enhances lightweight polyp segmentation baselines. Our proposed framework generates FM-specific prototype representations and aligns them semantically with the corresponding foundation model priors through reconstruction-based supervision. Subsequently, transformer-based fusion is introduced to highlight the polyp relevant representations, including salient boundary information, while preserving complementary semantic cues. Extensive experiments across five polyp segmentation benchmark datasets demonstrate that Lite-π significantly improves lightweight baselines, achieving superior generalization performance with minimal computational overhead and thereby, offering a practical solution for generalized polyp segmentation. Our code is available at GitHub. https://github.com/lostinrepo/Lite-Pi