. 2019 Apr 22;14(4):e0215521. doi: 10.1371/journal.pone.0215521

Table 4. Detected tie points and generated dense point cloud.

Tie Point Cloud
Points	159,939 of 178,838
RMS^a reprojection error^b	0.450277 (1.45519 pix)
Max reprojection error	1.37839 (42.9695 pix)
Mean key point size^c	3.41713 pix
Dense Point Cloud
Points	144,892,166

^a Root Mean Squared

^b Refers to the distance between the point on the image where a reconstructed 3D point can be projected, and the original projection of that 3D point detected on the photo and used as a basis for the 3D point reconstruction procedure.

^c Mean tie point scale averaged across all projections.