Auditing ambiguous multiview geometry.
Can independent geometric evidence help detect incorrect relationships that a reconstruction model assigns high confidence?
Updated September 26: the current reliability-adapter candidate is retired following a prior-art review. Sections 01–04 preserve the September 22 research question and plan; the dated updates below record the TUM comparison and subsequent decision.
2026-09-26: research decision and GeoCond prior artAdded 2026-09-26: the reviewed TUM comparison and public repositoryThe question
Similar appearance, different places
Unordered views of repeated windows, textures, or visually similar structures can admit competing geometric explanations. This study asks whether model confidence and independent geometric checks provide complementary evidence for identifying incorrect view relationships.
What would make a repair useful?
A controlled repair must improve independently checked correctness while preserving useful views and reconstruction completeness. Removing difficult inputs alone is insufficient: false alarms, disconnected views, lost coverage, runtime and memory all belong in the comparison.
Progress at first publication
First engineering run · 2026-09-22 · R1
MapAnything Apache ran successfully on the ordinary Middlebury Motorcycle stereo scene: two images, each preprocessed to 518 × 336, on an RTX 4060 Laptop GPU with 8188 MiB of memory. One cold-start run recorded 11.05 seconds of GPU-synchronized inference. This measures inference only, excluding model loading, export, download and setup; it is a single observation with no warm-up or repeated-run average.
Raw predictions, inspectable exports and a replayable recording have been retained. This establishes local execution and inspectable output; geometry accuracy, diagnosis and repair effectiveness remain unevaluated.
Protocol clarified
We have reviewed direct alternatives and specified a protocol with independent reference labels, strong baselines and stopping criteria. Revision 0.2 clarifies the order of error observation and repair, separate pose-confidence calibration, and how to assess improvement in the reconstruction output. Small-scale data entry points and a staged reproduction plan are documented.
What the comparison must include
MapAnything already offers native multiview confidence. Doppelgangers++ and XDG address pairwise visual disambiguation and filter candidate relationships. These existing capabilities set the baseline: a combination of confidence and geometric signals needs to demonstrate additional value under the same inputs and false-removal constraints.
Evidence status · 2026-09-22
Ordinary engineering scenes completed: 1. Research scenes reviewed under protocol 0.2: 0. The engineering run used protocol 0.1; revision 0.2 preserves its engineering acceptance criteria. The execution record remains tied to its original version. Independent research validation is pending.
How to assess a result
An independent reference
Correctness labels need evidence beyond the reconstruction being tested. A consistent cycle derived from the same global poses can repeat the same error. Lower optimization residuals alone cannot establish that visual ambiguity has been resolved.
Observe errors before deciding to repair
Initial geometry-error observations come before the gate for controlled repair. The requirements for multiple independent scenes, a second model and held-out improvement determine whether to attempt repair or expand the study. They do not require failures to be established before observation can begin.
Calibrate pose confidence separately
High-confidence pose errors need a separate calibration using motion-capture reference poses, with thresholds fixed for each model, checkpoint, preprocessing and four-view context. Surface-identity labels cannot replace pose-correctness labels. If calibration is insufficient, ordinary reference-confirmed errors remain reportable while the high-confidence classification stays unavailable.
Measure repair in the output
A repair must reduce independently confirmed errors in the final reconstruction while preserving views and geometric coverage. Removing candidate edges is an intermediate measurement. If the reconstruction backend already rejected an edge and its removal produces no independently verified output improvement, the outcome is no repair benefit.
A reproducible record
Each result should identify the scene and input provenance, model and code revisions, configuration, actual sample count, reference construction, measured costs and replay command. Failed or unresolved cases remain part of the record.
Start small, keep the reference separate
The first reference-backed control is a four-frame TUM RGB-D sequence with motion-capture poses. Pairwise ambiguity evaluation will use published surface-identity labels, with calibration and held-out data separated by physical scene. These are planned inputs; selected images, hashes and actual counts must be frozen before evaluation.
What the first run can establish
A successful ordinary-scene run establishes local execution and inspectable output. Evidence for a new diagnostic method requires comparison across independent scenes, strong alternatives and held-out data.
Starting points
These upstream projects are starting points for the reproduction and method comparison. Their results remain attributable to their authors.
Earlier evidence
The First Generation report retains the published results, negative evidence and reproduction paths that inform this approach to evaluation.
Read the preserved closure reportTUM reference comparison
A public, checkable experiment
GeometryAudit now contains the two recorded P0 engineering cases, their protocols, compact records and independent reviews. The repository was published on September 23. This update reports the TUM run and CPU review completed on September 22; the R1 account above retains its original publication date and scope.
One four-frame reference window
MapAnything Apache processed four TUM RGB-D freiburg1_xyz images together at 518 × 392 on the same RTX 4060 Laptop GPU. One GPU-synchronized inference took 11.870 seconds, excluding loading, export and preparation. The model received RGB images; motion-capture poses were used separately for comparison.
The independently reviewed record contains six relative rotation errors, 0.585605–3.021899°, and five translation-direction errors, 5.493252–8.439680°. Pair 1–2 has a 0.026964 m reference baseline, below the declared 0.05 m direction-evaluation threshold, so its translation result remains unavailable and is excluded from that denominator.
What these numbers establish
The independent CPU review checked frame selection, reference matching, coordinate conventions and the six pair calculations against the saved model output. All pairs share cameras within one ordinary window. Reference noise has not been independently bounded; this evidence supports a recorded numerical comparison, with diagnosis, confidence calibration and repair still unvalidated.
Recompute without a GPU
The public CPU entry point rebuilds the reference rotations from recorded quaternions and recalculates the comparison from saved camera matrices. It needs Python and NumPy, with no model or image download. This checks the published record; running the model afresh uses the separate reproduction guide and external artifacts.
Research decision after prior-art review
The current candidate is retired
The prior-art review identified substantial overlap with GeoCond, published September 16. Its geometry-conditioned pose reliability estimates and refinement gating directly address the central reliability-adapter contribution proposed here. This closes the current candidate definition and its planned implementation and failure-space audit.
Why the assessment changed
GeoCond combines native confidence with geometry-related features extracted from backbone outputs, uses pose-graph cycle residuals as one supervision signal, and evaluates uncertainty and selective refinement. These model-derived signals are not independent ground-truth references, and its cross-backbone results do not establish universal improvement. The overlap in the core research question is nevertheless enough to withdraw our earlier claim of an unoccupied contribution.
GeoCond · version 1 paperWhat remains useful
GeometryAudit preserves the recorded runs, original protocols, compact camera records and CPU pose checks for inspection and reproduction. The R1 and TUM results retain their original scope; no new reliability or repair result is claimed. Any future research candidate will need its own question and prior-art assessment.