GAMMA: Generalizable Alignment via Multi-task and Manipulation-Augmented Training for AI-Generated Image Detection. - Haozhen Yan; Yan Hong 001; Suning Lang; Jiahui Zhan; Yikun Ji; Yujie Gao 001; Jun Lan; Huijia Zhu; Weiqiang Wang 002; Jianfu Zhang 003 (CoRR, 2025)