Chinese Ancient Coin Patina Authentication Method Based on Frequency-Domain Features and Multi-task Learning
HUANG Jie1,2, TIAN Zhanhong1,2
1. College of Electrical Engineering and Automation, Fuzhou Uni-versity, Fuzhou 350108; 2. 5G+ Industrial Internet Institute, Fuzhou University, Fuzhou 350108
Abstract:The high macroscopic visual similarity between authentic and fake patina on ancient coins limits the discriminative capability of traditional spatial-domain models. Existing methods struggle to solve the continuous scoring problem of the physical evolution degree of patina. To address the above issues, a Chinese ancient coin patina authentication method based on frequency-domain features and multi-task learning(FDF-MTL) is proposed. First, a frequency-domain feature extraction and enhancement module is designed. Patch-based discrete cosine transform is adopted to capture the essential differences in frequency energy distribution between authentic patina and fake patina. A dual-path pooling strategy is utilized to perceive abnormal frequencies. Second, a multi-scale spatial-frequency modulation fusion module is constructed to transform frequency-domain features into attention weights for modulating spatial-domain features, thereby avoiding semantic conflicts. Finally, a fused feature screening module is designed to suppress the interference of coin inscription contours, and a multi-task learning framework is constructed to solve the scoring problem. The joint optimization of authenticity discrimination and continuous patina score regression is achieved. Experiments on a self-built dataset demonstrate the superior performance of the proposed method in both authenticity discrimination and patina scoring tasks.
黄捷, 田展宏. 基于频域特征与多任务学习的中国古钱币包浆鉴别方法[J]. 模式识别与人工智能, 2026, 39(7): 621-635.
HUANG Jie, TIAN Zhanhong. Chinese Ancient Coin Patina Authentication Method Based on Frequency-Domain Features and Multi-task Learning. Pattern Recognition and Artificial Intelligence, 2026, 39(7): 621-635.
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