COLMAP vs MicMac

COLMAP is a free pipeline for reconstructing scenes in 3D from ordered or unordered image collections. Its Structure-from-Motion stage estimates camera poses and sparse 3D structure; its Multi-View Stereo stage uses PatchMatch stereo and stereo fusion to produce dense point clouds and meshes. Users can work through a graphical interface or command line. The GUI’s automatic reconstruction tool accepts an image folder and creates sparse and dense results in a workspace folder. For development, PyCOLMAP offers Python bindings for most functionality, and COLMAP can be built as a library for C++ code. Feature extraction options include SIFT, ALIKED, and LoMa; ALIKED and LoMa require ONNX support at build time. It supports a range of camera models and multi-camera rigs. Users can install pre-built binaries or build from source; macOS users also have a Homebrew formula, and a pre-built Docker image includes CUDA support. The library uses the new BSD license, while third-party dependencies have separate licenses. The project describes COLMAP as research software that may occasionally exit ungracefully when constraints are not met.

MicMac is free, open-source desktop software for reconstructing 3D models from imagery. Developed at IGN and ENSG within the LASTIG lab, it runs on Linux, macOS and Windows under the CECILL-B license. It supports frame cameras, pushbroom sensors and scanned analogue images, along with camera calibration models and dense image matching for deformation studies. Outputs can include point clouds, 3D models and ortho-imagery in a desired coordinate system. Intermediate results in open formats let users work at different stages, and quality indicators include bundle adjustment residuals, covariance matrices, parameter sensitivity and correlation images. The C3DC command computes a point cloud from oriented images; AperiCloud creates a sparse cloud with camera positions and orientations for viewing in MeshLab, but does not support 64-bit PLY. MicMac is adapted to big datasets and was initially built for experts and researchers, with use also described in architecture, archaeology and forestry. Documentation, tutorials, a wiki and user forum are available. Building from source involves multiple dependencies, and the Mac guide cautions that a current revision may not compile or may be unstable on a given OS.