Few-Shot Learning for Plant-Disease Recognition in the Frequency Domain.

Abstract

Few-shot learning (FSL) is suitable for plant-disease recognition due to the shortage of data. However, the limitations of feature representation and the demanding generalization requirements are still pressing issues that need to be addressed. The recent studies reveal that the frequency representation contains rich patterns for image understanding. Given that most existing studies based on image classification have been conducted in the spatial domain, we introduce frequency representation into the FSL paradigm for plant-disease recognition. A discrete cosine transform module is designed for converting RGB color images to the frequency domain, and a learning-based frequency selection method is proposed to select informative frequencies. As a post-processing of feature vectors, a Gaussian-like calibration module is proposed to improve the generalization by aligning a skewed distribution with a Gaussian-like distribution. The two modules can be independent components ported to other networks. Extensive experiments are carried out to explore the configurations of the two modules. Our results show that the performance is much better in the frequency domain than in the spatial domain, and the Gaussian-like calibrator further improves the performance. The disease identification of the same plant and the cross-domain problem, which are critical to bring FSL to agricultural industry, are the research directions in the future.

Plant phenotyping relevance

植物病害状態を画像から認識するための周波数領域表現、周波数選択、分布較正手法を開発しており、病害表現型の抽出が研究の中心である。

Code and data availability

The paper's plant-disease recognition experiments are built on the PlantVillage dataset, which the authors explicitly state is publicly available at a Mendeley Data URL. No author analysis code, models, or checkpoints are disclosed.