feedBack/lib
ChrisBeWithYou 1bccb8a9e8
feat(midi): convert_midi_tempo_map — extract tempos, time signatures, beat grid (#796)
* feat(midi): convert_midi_tempo_map — extract tempos, time signatures, beat grid

The keys/drums MIDI converters always built a tempo-aware tick->seconds
map internally (to bake note times) and then discarded it — and never
read time_signature meta at all — so every MIDI import landed with no
bars, no measures, and an implied 4/4 no matter what the file said.

New lib/midi_import.py helper convert_midi_tempo_map(midi_path,
track_index) extracts the grid a .mid actually carries:

- tempos: {time, bpm} per tempo event (deduped per tick, 120 default)
- time_signatures: {time, ts: [num, den]} — the song-timeline shape
- beats: one row per beat on the editor grid shape — numbered downbeats
  with a den hint, measure:-1 interior beats; the beat unit follows the
  active signature (6/8 = six eighth-note rows per bar)

Event scope mirrors _build_tick_to_seconds: SMF type 0/1 merge meta
from all tracks, type 2 reads ONLY the chosen track (independent
timelines — callers must never share one grid across type-2 tracks).
Mid-bar signature events (ill-formed but seen in the wild) apply at the
next bar boundary. All times compute from absolute ticks through the
cumulative tempo table and round once at emit — rounding error never
accumulates with song length. A bar-count safety valve guards malformed
files. Consumer: the editor's multitrack MIDI import (tempo-seed
dialog, feedBack-plugin-editor roadmap Phase 3).

Tests: tests/test_midi_tempo_map.py — 10 cases driving the REAL
function against real .mid files built with mido (no stubs): default
grid, tempo bends, 500-bar rounding-drift check, 4/4->3/4 and 6/8
signatures, mid-bar signature deferral, duplicate-tick last-wins,
type-2 meta isolation from a bogus sibling track, empty files, grid
coverage bounds. Full MIDI-adjacent suite green: 55 passed
(test_midi_tempo_map + test_midi_import + test_midi_import_drums +
test_gp2midi) under the project venv.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01JEoFeTPSnz4NpwwCG52hnu

* fix(midi): make convert_midi_tempo_map robust — real division guard, symmetric tempo default, single-pass meta

- Push the ticks-per-beat fallback into _build_tick_to_seconds (the single
  place ticks route through), guarding on `> 0` so a division==0 (malformed)
  or negative SMPTE-division header no longer raises ZeroDivisionError or
  walks the beat grid into negative times. Mirror the guard at the
  convert_midi_tempo_map beat_ticks site. The local `or 480` was cosmetic
  before — the closure still divided by the raw division.
- Seed tempos_out with a 120 BPM row at time 0 when the first set_tempo
  lands after tick 0, symmetric with the (0, 4, 4) time-signature default,
  so the sidecar matches the grid the head of the song actually used.
- Collapse the duplicated meta_source/note_source lists into one
  source_tracks walked in a single pass (meta collection + end_tick).
- Fix a weak assert in test_mid_bar_signature_applies_at_the_next_boundary
  (operator-precedence `(A and B) or C`) to assert den == 4 outright.
- Add tests: non-positive division (0 + negative SMPTE), first tempo after
  start seeds 120@0, explicit SMF type-0 file, and the _TEMPO_MAP_MAX_BARS
  safety valve.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: ChrisBeWithYou <chris@rifflarr.local>
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
Co-authored-by: byrongamatos <xasiklas@gmail.com>
2026-07-07 10:27:17 +02:00
..
acoustid_match.py feat(enrichment): AcoustID audio-fingerprint identification (opt-in) (#759) 2026-07-05 00:17:43 +02:00
audio.py rename: slopsmith → feedBack, byron → got-feedBack (#537) 2026-06-23 11:03:01 +02:00
diagnostics_bundle.py rename: slopsmith → feedBack, byron → got-feedBack (#537) 2026-06-23 11:03:01 +02:00
diagnostics_hardware.py rename: slopsmith → feedBack, byron → got-feedBack (#537) 2026-06-23 11:03:01 +02:00
diagnostics_redact.py fix(tests): isolate plugin routes modules + redact .feedpak filenames (#736) 2026-07-03 13:01:07 +02:00
drums.py rename: slopsmith → feedBack, byron → got-feedBack (#537) 2026-06-23 11:03:01 +02:00
env_compat.py rename: slopsmith → feedBack, byron → got-feedBack (#537) 2026-06-23 11:03:01 +02:00
gp2midi.py rename: slopsmith → feedBack, byron → got-feedBack (#537) 2026-06-23 11:03:01 +02:00
gp2notation.py rename: slopsmith → feedBack, byron → got-feedBack (#537) 2026-06-23 11:03:01 +02:00
gp2rs_gpx.py feat(gp_autosync): piecewise time-warp helpers + refine_sync onset pass (#787) 2026-07-05 20:08:19 +02:00
gp2rs.py fix(gp-import): correct bass string count, lead/rhythm roles, preview note count (#601) 2026-06-26 18:58:35 +02:00
gp8_audio_sync.py rename: slopsmith → feedBack, byron → got-feedBack (#537) 2026-06-23 11:03:01 +02:00
gp_autosync.py fix(gp_autosync): slope-constrained DTW steps — stop path collapse on riff-based songs (#791) 2026-07-05 23:12:31 +02:00
jsonc.py feat(core): read .jsonc data files (strip C-style comments) (feedpak-spec §8) 2026-06-20 14:10:04 -07:00
logging_setup.py rename: slopsmith → feedBack, byron → got-feedBack (#537) 2026-06-23 11:03:01 +02:00
loosefolder.py Improve wording in terminology cleanup 2026-06-16 19:43:45 +01:00
lyrics_transcribe.py rename: slopsmith → feedBack, byron → got-feedBack (#537) 2026-06-23 11:03:01 +02:00
mb_match.py feat(enrichment): alias-aware scoring — auto-confirm non-Latin-primary artists (#772) 2026-07-05 01:11:38 +02:00
midi_import.py feat(midi): convert_midi_tempo_map — extract tempos, time signatures, beat grid (#796) 2026-07-07 10:27:17 +02:00
notation_lift.py fix: correctly import and notate multi-staff (piano/keys) tracks from GP8 (#692) 2026-07-02 08:40:20 +02:00
notation.py rename: slopsmith → feedBack, byron → got-feedBack (#537) 2026-06-23 11:03:01 +02:00
progression.py Improve wording in terminology cleanup 2026-06-16 19:43:45 +01:00
safepath.py fix(library): serve art/load for songs mounted through a library junction (#766) 2026-07-05 00:15:50 +02:00
scan_worker.py fix: Edit Metadata persists into .feedpak files (suffix gate predated the rename) (#725) 2026-07-02 20:51:57 +02:00
sloppak.py Drop dead whisperx entry from allowed lyrics_source set 2026-07-06 17:30:26 -04:00
song_score.py Clean release snapshot 2026-06-16 18:47:13 +02:00
song.py fix(gp-import): correct bass string count, lead/rhythm roles, preview note count (#601) 2026-06-26 18:58:35 +02:00
songmeta.py library: opt-in gap-fill — write confirmed missing metadata into the pack (R4a) (#724) 2026-07-02 20:52:11 +02:00
tailwind_rebuild.py rename: slopsmith → feedBack, byron → got-feedBack (#537) 2026-06-23 11:03:01 +02:00
tones.py rename: slopsmith → feedBack, byron → got-feedBack (#537) 2026-06-23 11:03:01 +02:00
tunings.py settings: add host instrument profiles (#753) 2026-07-05 00:16:42 +02:00
vocal_pitch.py rename: slopsmith → feedBack, byron → got-feedBack (#537) 2026-06-23 11:03:01 +02:00
wem_decode.py rename: slopsmith → feedBack, byron → got-feedBack (#537) 2026-06-23 11:03:01 +02:00
xp.py Clean release snapshot 2026-06-16 18:47:13 +02:00