File Formats

OCTAVE reads and writes the standard Clone Hero / YARG song-folder layout.

Song folder structure

My Song - Some Artist/
├── notes.mid          # Required — multi-track MIDI chart
│   └── (or notes.chart for legacy Clone Hero charts)
├── song.ini           # Required — metadata
├── album.png          # Optional — album art (jpg also accepted)
├── song.ogg           # Backing track (everything not in another stem)
├── drums.ogg          # Optional drum stem (or drums_1..4.ogg)
├── bass.ogg           # Optional
├── guitar.ogg         # Optional
├── keys.ogg           # Optional
├── vocals.ogg         # Optional (or vocals_1..3.ogg)
├── crowd.ogg          # Optional
└── video.mp4          # Optional chart video

Audio can be .ogg (Vorbis), .opus, or .mp3. OCTAVE never re-encodes existing audio on save.

notes.mid

Standard format-1 MIDI with one track per instrument:

Track name	Instrument
PART DRUMS	Drums (5-lane / Pro)
PART GUITAR	Lead guitar (5-fret)
PART BASS	Bass guitar (5-fret)
PART KEYS	Keys (5-fret)
PART REAL_KEYS_X	Pro Keys (Expert / Hard / Medium / Easy)
PART REAL_GUITAR	Pro Guitar (6-string × 22 frets)
PART REAL_BASS	Pro Bass
PART VOCALS	Lead vocals + lyrics
HARM2 / HARM3	Vocal harmonies
EVENTS	Practice sections, lighting cues
BEAT	Beat track for strikeline timing
VENUE	Venue lighting and camera cuts

OCTAVE preserves any track it doesn't understand, so round-tripping a chart is safe.

notes.chart

Plain-text Clone Hero format. OCTAVE converts to/from MIDI internally — saving a .chart source song writes back as .chart; saving a .mid source writes .mid.

song.ini

Standard Clone Hero [song] section. OCTAVE writes:

[song]
name = My Song
artist = Some Artist
album = An Album
genre = Rock
year = 2024
charter = OCTAVE
song_length = 215000
preview_start_time = 30000
delay = 0
diff_band = 4
diff_drums = 5
diff_guitar = 4
diff_bass = 3
diff_keys = 3
diff_vocals = 4

Any extra fields present in the original file are preserved.