The perceptual cluster was producing one giant first group that
contained hundreds of unrelated images. Two causes:
- Solid-colour images (skies, black frames, monochrome scans) all
hash to near-zero pHashes that Hamming-distance-zero to each other.
- Single-link clustering on pHash alone is too permissive — a chain
of weakly-similar images all collapses into one cluster.
Fixed by skipping hashes outside the popcount [8, 56] band (uniform
content) and requiring dHash agreement within threshold before
unioning a candidate edge from the BK-tree. Two new tests pin both
invariants.
Backfill bin separately fix: decode-failed rows kept phash_64=NULL
and got re-pulled by every batch, infinite-looping on a queue of
unbreakable formats. Persist a 0/0 sentinel on decode failure so
the row leaves the candidate set; the all-zero hash is excluded
from clustering by the same entropy filter so it doesn't pollute
results.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Adds pHash + dHash columns alongside the existing blake3 content_hash so
near-duplicates (re-encoded, resized, format-converted copies) become
queryable. /duplicates/{exact,perceptual} return groups; /duplicates/
{resolve,unresolve} flip a duplicate_of_hash soft-mark on losing rows
and union perceptual-only tag sets onto the survivor. The default
/photos listing filters duplicate_of_hash IS NULL so demoted siblings
stop cluttering the grid; include_duplicates=true opts back in for
Apollo's review modal. Upload now hashes bytes pre-write and returns
409 with the canonical sibling when a file's bytes already exist.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Cameron Cordes