Fig. 3

Serial ET volumes alignment diagram. Serial ET volume alignment is mainly divided into two steps. First coarse alignment. It is based on feature matching and affine transformation, and uses multi-resolution images to achieve rough alignment of target structures. Second fine alignment. After the coarse alignment of the volumes, based on the clear texture structure of the high-magnification image, use block matching, BP-Elastic, and thin plate spline to obtain the fine-tuning deformation fields. Then, apply them to serial volumes to correct the alignment of target structures between adjacent volumes