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name: mapping-localization description: "Operate hloc pair generation, COLMAP/pycolmap mapping, triangulation, SfM localization, InLoc localization, and pose outputs." disable-model-invocation: true metadata: disco-role: operating license: Apache 2.0

mapping-localization

Use this sub-skill when the task is to turn prepared hloc features, retrieval descriptors, matches, image lists, and/or existing camera poses into image pairs, COLMAP/pycolmap sparse models, triangulated reference models, or query poses.

Route here for

• Pair files from exhaustive image sets, retrieval descriptors, covisibility, or known poses.
• hloc.reconstruction.main / python -m hloc.reconstruction sparse reconstruction.
• hloc.triangulation.main / python -m hloc.triangulation triangulation from known camera poses.
• hloc.localize_sfm.main / python -m hloc.localize_sfm query localization against a COLMAP/pycolmap SfM model.
• hloc.localize_inloc.main / python -m hloc.localize_inloc InLoc-style RGB-D scan localization.
• NVM-to-COLMAP import planning with python -m hloc.colmap_from_nvm.

Route away

• Feature extractor, global descriptor, dense matcher, sparse matcher, or built-in config selection details: use ../feature-retrieval/.
• Benchmark-specific directory/download/submission layouts such as Aachen, 4Seasons, RobotCar, or complete InLoc dataset setup: use ../dataset-pipelines/.
• Creating custom extractors/matchers or external HDF5 feature/match exports: use ../custom-interop/.

Required operating contract

Before running mapping or localization, identify these artifacts explicitly:

1. Image root and any image/query list files.
2. Pair or retrieval file, with exactly two whitespace-separated image names per line.
3. HDF5 local features and HDF5 matches with hloc-compatible group/dataset names.
4. For reconstruction: output SfM directory, image directory, feature file, match file, and pair file.
5. For triangulation/localization: a reference COLMAP/pycolmap model directory with binary model files.
6. For query localization: query intrinsics list and output pose path.
7. For InLoc-style localization: retrieval pairs, query/database feature and match files, and scan/alignment files in the dataset tree.

Run the bundled validator when accepting user-supplied paths or text files:

python sub-skills/mapping-localization/scripts/validate_hloc_inputs.py \
  --workflow localize-sfm \
  --query-list queries_with_intrinsics.txt \
  --pairs retrieval.txt \
  --features features.h5 \
  --matches matches.h5 \
  --reference-model sfm_model

References

• Workflow recipes
• API and CLI reference
• Data contracts
• Troubleshooting
• Input validator