[Zador-Pataki]

Motivation

Support calibrated monocular and synchronized multi-camera input, using known camera calibration and fixed sensor poses throughout reconstruction.

Changes

• Input and calibration

  • Configure camera calibration and fixed sensor poses in rig.cameras, and represent synchronized inputs with COLMAP cameras, rigs, and frames.
  • Undistort calibrated distorted images before reconstruction. Limited preliminary evidence suggests DA3 and RoMa produce better estimates on undistorted inputs; this choice needs further evaluation.

• Keyframing and matching

  • Select keyframe timestamps using a configurable camera, retaining all synchronized camera images at each selected timestamp.
  • Build temporal feature tracks separately within each camera stream.
  • Match configured camera pairs at the same timestamp to connect overlapping views. For camera pairs with reliable overlap and little risk of visual aliasing, matches can be flagged internally as “sequential matches” to use the corresponding optimization losses. Other pairs use loop-closure losses.
  • Retrieve loop-closure matches across cameras and timestamps.

• Reconstruction and visualization

  • Estimate one shared pose per synchronized capture, keeping the calibrated relative camera rotations and translations fixed throughout rotation averaging, global positioning, and bundle adjustment.
  • Step through synchronized camera images together in the viewer.