Videos deduped on sha256 only (pHash is images-only), so a different encode/remux
of the same clip imported as a distinct record — the "same video from multiple
sources" clutter surfaced by #859.
Tier-1 metadata fingerprint: identity = container duration (±1.0s) + matching
aspect ratio, scoped to the same artist; quality axis = pixel dimensions (mirrors
image pHash: larger_exists→skip+link, smaller_exists→supersede). Codec/bitrate
are deliberately NOT part of identity (the point is matching across re-encodes).
Tight tolerances because a wrong video merge is destructive.
- image_record.duration_seconds (Float, nullable; migration 0052). NULL for images.
- safe_probe.probe_video also reads format=duration (one extra ffprobe field on the
call that already runs); ProbeResult.duration.
- _find_similar_video(duration,w,h,artist) shared by both import pipelines.
- _import_media (filesystem/archive path): captures duration, video near-dup
branch, persists duration.
- attach_in_place (download path — handles #859's videos, previously didn't probe
video at all): best-effort probe for dims+duration (LENIENT — never newly rejects
a downloaded video on probe failure), video near-dup branch, persists duration.
- _supersede carries duration onto the kept row.
Reuses SkipReason.duplicate_phash so the existing download/external dup-cleanup
(path-safe unlink, #859) applies unchanged. Tests: skip-smaller, supersede-larger
(+ duration adopted), and distinct-durations-not-merged (false-merge guard).
Follow-up (Phase 2, #871): a backfill to re-probe NULL-duration existing videos so
the current library participates in dedup; retroactive merge of existing dups is a
separate destructive maintenance action.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
