Multi-image Overlap Stitching and Automatic Image Construction for Coherent X-ray Imaging

Abstract

Direct-space and real-time coherent X-ray imaging (direct-CXI) enables visualization of magnetic-domain structures and dynamics over length scales exceeding the field of view of a single image. However, large-area measurements typically require raster scanning, producing hundreds of partially overlapping images that must be accurately aligned and combined before quantitative analysis can be performed. Here, we present Multi-image Overlap Stitching and Automatic Image Construction for coherent X-ray imaging (MOSAICX), an automated stitching workflow for large-area direct-space coherent X-ray imaging. The workflow consists of image centering, masking, trimming, binarization, hierarchical stitching, and post-processing. To demonstrate the method, we apply it to a dataset comprising 434 direct-CXI images of the antiferromagnetic topological insulator MnBi$_2$Te$_4$. The images are first combined into column reconstructions and subsequently stitched into a single large-area composite image. The resulting reconstruction reveals the complete magnetic-domain and domain-wall landscape over the scanned region while suppressing imaging artifacts and detector defects. The presented workflow provides an efficient approach for processing large direct-CXI datasets and enables visualization and analysis of magnetic-domain structures beyond the field of view of individual measurements.