This is an open-source package for passive seismic imaging. The methodology is detailed in Chen, Y., O.M. Saad, M. Bai, X. Liu, and S. Fomel, 2021, A compact program for 3D passive seismic source-location imaging, Seismological Research Letters. A PROOF version of the paper can be found at https://drive.google.com/file/d/1jAkbbAsGbpBqjzzjVogDcN7vnmmrgfqk/view?usp=sharing