Add RANSAC/match-count diagnostics to exhaustive_matcher

Mårten Åsberg committed on 2026-08-03 at 14:11

Real-data testing showed near-total geometric verification failure
(3/3081 pairs at min_score=0.0, 0/3071 at min_score=0.2 -- getting
worse with a stricter threshold rules out "too much noise" as the
sole explanation). The pass/fail count against MIN_INLIERS alone
can't distinguish "pairs are landing just under the threshold" from
"there's a correctness bug upstream of RANSAC", so report the actual
best-inlier-count and raw-match-count distributions across all
candidate pairs to tell those apart.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

Browse files at this commit

src/exhaustive_matcher.rs +43 -0

diff --git a/src/exhaustive_matcher.rs b/src/exhaustive_matcher.rs
index 522b90f..1f8443e 100644
@@ -204,6 +204,49 @@ pub fn run(cfg: ExhaustiveMatcherConfig) -> Result<()> {
    .collect();
  ransac_pb.finish();
  // Diagnostics: raising --min_score made verification *worse* rather than better,
  // which rules out "too much low-confidence noise" as the sole explanation. Report
  // the actual best-inlier-count RANSAC found per pair (not just pass/fail against
  // MIN_INLIERS) and raw match counts, so we can see the real shape of the data.
  {
    let percentile = |sorted: &[usize], p: usize| -> usize {
      if sorted.is_empty() {
        0
      } else {
        sorted[(sorted.len() - 1) * p / 100]
      }
    };
    let mut best_inliers: Vec<usize> = ransac_results
      .iter()
      .map(|r| r.as_ref().map_or(0, |r| r.inliers.len()))
      .collect();
    best_inliers.sort_unstable();
    let no_model_count = ransac_results.iter().filter(|r| r.is_none()).count();
    let mut raw_counts: Vec<usize> = pending.iter().map(|p| p.matched.len()).collect();
    raw_counts.sort_unstable();
    eprintln!(
      "[diag] RANSAC found <8 inliers (no model) for {no_model_count}/{} pairs",
      ransac_results.len()
    );
    eprintln!(
      "[diag] best inlier count per pair: p10={} p50={} p90={} max={}",
      percentile(&best_inliers, 10),
      percentile(&best_inliers, 50),
      percentile(&best_inliers, 90),
      best_inliers.last().copied().unwrap_or(0)
    );
    eprintln!(
      "[diag] raw LightGlue match count per pair: p10={} p50={} p90={} max={}",
      percentile(&raw_counts, 10),
      percentile(&raw_counts, 50),
      percentile(&raw_counts, 90),
      raw_counts.last().copied().unwrap_or(0)
    );
  }
  let mut verified_pairs = 0usize;
  let mut total_inliers = 0usize;
  for (pair, result) in pending.iter().zip(ransac_results.iter()) {