Lin Ruoqian, Zhang Rui, Wang Chunyang, Yang Xiao-Qing, Xin Huolin L
Chemistry Division, Brookhaven National Laboratory, Upton, NY, 11973, USA.
Department of Physics and Astronomy, University of California, Irvine, CA, 92697, USA.
Sci Rep. 2021 Mar 8;11(1):5386. doi: 10.1038/s41598-021-84499-w.
Atom segmentation and localization, noise reduction and deblurring of atomic-resolution scanning transmission electron microscopy (STEM) images with high precision and robustness is a challenging task. Although several conventional algorithms, such has thresholding, edge detection and clustering, can achieve reasonable performance in some predefined sceneries, they tend to fail when interferences from the background are strong and unpredictable. Particularly, for atomic-resolution STEM images, so far there is no well-established algorithm that is robust enough to segment or detect all atomic columns when there is large thickness variation in a recorded image. Herein, we report the development of a training library and a deep learning method that can perform robust and precise atom segmentation, localization, denoising, and super-resolution processing of experimental images. Despite using simulated images as training datasets, the deep-learning model can self-adapt to experimental STEM images and shows outstanding performance in atom detection and localization in challenging contrast conditions and the precision consistently outperforms the state-of-the-art two-dimensional Gaussian fit method. Taking a step further, we have deployed our deep-learning models to a desktop app with a graphical user interface and the app is free and open-source. We have also built a TEM ImageNet project website for easy browsing and downloading of the training data.
以高精度和稳健性对原子分辨率扫描透射电子显微镜(STEM)图像进行原子分割与定位、降噪及去模糊是一项具有挑战性的任务。尽管一些传统算法,如阈值处理、边缘检测和聚类,在某些预定义场景中能取得合理性能,但当背景干扰强烈且不可预测时,它们往往会失效。特别是对于原子分辨率的STEM图像,到目前为止,还没有一种成熟的算法能够在记录图像存在较大厚度变化时,稳健地分割或检测所有原子列。在此,我们报告了一个训练库和一种深度学习方法的开发,该方法能够对实验图像进行稳健且精确的原子分割、定位、去噪和超分辨率处理。尽管使用模拟图像作为训练数据集,但深度学习模型能够自适应实验STEM图像,并在具有挑战性的对比度条件下的原子检测和定位中表现出色,其精度始终优于当前最先进的二维高斯拟合方法。更进一步,我们已将深度学习模型部署到一个带有图形用户界面的桌面应用程序中,该应用程序是免费且开源的。我们还建立了一个TEM ImageNet项目网站,以便于浏览和下载训练数据。