map_merge_3d provides services for merging 3D maps represented as pointclouds.
This package contains ROS node, two tools for offline merging of pcd files and a library API.
This library use PCL to manipulate pointclouds.
Simple to use interface for merging arbitrary number of maps. You need just
See Map merging
Modules Features and Matching provide functions for extracting features, keypoints and various functions for estimating transformations. Those functions might come handy if you want to do custom pre- or post-processing.