Downcharter+

Chart reducer, venue generator and native Rock Band 3 packager for YARG, Rock Band 3 and Clone Hero.

Most customs ship with only an Expert chart. Downcharter+ takes that .mid or .chart and fills in the rest: the lower difficulties for every instrument, a venue with camera and lights, character animations, talky vocals from the lyrics, and audio-driven lipsync. It then packages the result natively for the platform you play on — a PS3/RPCS3 folder, an Xbox 360 CON, or a YARG/Clone Hero .sng — with no external converter needed.

What it covers:

• Difficulty reduction for guitar, bass and keys — Hard, Medium and Easy
• Drum reduction across all three difficulties, plus Expert+ (2× kick) detection
• Venue generation — camera cuts, lights, post-processing, pyro and animations
• Talkies charted from the lyrics, with note ends trimmed against the vocal stem
• Audio-driven lipsync (mouth + blink/brow/squint), packaged in a native .milo and validated frame-by-frame against official RB3 lipsync
• Vocal stem separation (MDX-NET) when the song has no isolated stems — GPU (DirectML) with CPU fallback
• Native packaging: PS3/RPCS3 song folder, Xbox 360 CON, YARG/CH .sng

The reductions try to stay close to what a human charter would do — they keep the groove and the riff intact instead of quantizing everything to a grid, preserve sustains and pitch contour, and keep the BEAT track running to the end so the characters don't freeze mid-song.

---

Guitar & Drum reductions

Difficulties are worked out from the beat grid rather than hard-coded for a given BPM, and they cascade down from Expert (Expert → Hard → Medium → Easy) so each level stays consistent with the one above it.

Guitar / Bass / Keys — pitch contour preserved:

Difficulty	Rules
Hard	from Expert · real HOPOs · no green+orange or 3-note chords · sustain gap 1/16
Medium	min spacing 1/4 · gap-fill + beat-snap · all strum · sustain gap 1/4
Easy	min spacing dotted-1/4 (1.5 beat) · no chords · all strum · sustain gap 1/4

Drums — groove-preserving:

• Kick / snare / pad thinning on an adaptive grid, fills collapsed per difficulty
• Doubles preserved · 3+ fast kicks → alternating = Expert+
• A groove-check quality guard flags any reduction that loses the feel (logged to a session file)

For Rock Band, the Expert chart also gets a hand-position map (force-HOPO/strum markers derived from 100 official charts) and full drum limb animations with realistic sticking, including strict alternation through fills.

---

Venue generation

▶️ Watch the full demo

Generates camera cuts, lights, post-processing, spotlights, pyro and character animations, with a theme chosen to fit the song. Everything is calibrated against 100 official RB3 charts: a director pass makes song-level decisions once (repeated sections reuse their look, section boundaries share anchors, the last chorus gets the official 1.5× lighting climax), and the RNG is seeded from the song's content so the same song always gets the same venue.

The camera won't point at an instrument that isn't playing — and the vocalist's cuts and spotlight only fire on real sung vocals (chart/lyrics), never on an audio-analysis guess. If a song already has a hand-authored venue, it's left alone.

If audio is present (.ogg, .opus, .wav, .flac, .mp3, .mogg), it's used to read the actual loudness of each section — a loud chorus vs. a quiet verse — which feeds the cuts and lights.

---

Talkies & lipsync

Charts unpitched (talky) vocals in PART VOCALS straight from the lyrics, so the characters sing and lip-sync even on songs that only have lyrics and no vocal chart. These are real vocal tubes the engine drives from, not just a lipsync track.

Without pitch info, the tricky part is knowing how long each note should last. If an isolated vocal stem is available, Downcharter+ reads the voice's RMS envelope and ends each note where the singer actually stops. With no separate stem it extracts the vocal channels from an unencrypted .mogg, or separates one from the mix with MDX-NET (GPU via DirectML, CPU fallback). A real stem is worth having — it drives both the sustain trimming and the per-syllable mouth weight.

The lipsync itself is phoneme-based (CMUdict + rule G2P → visemes) and follows the official articulation model: the mouth opens ~0.12 s before each tube and closes ~0.12 s after it, vowels hold for the tube's whole length, melisma (+) tubes keep it open, and back-to-back syllables connect legato instead of punching shut. Blinks, brow and squint keyframes ride along. Compared frame-by-frame against 15 official RB3 milos, the generated lipsync agrees on mouth state 88% of the time (96% open-when-they're-open), with episode lengths matching the official envelope.

---

Rock Band 3 packaging (native)

The Convert tab turns a processed song folder into a ready-to-install package — no Magma, no Onyx:

• PS3 / RPCS3 folder — songs/<id>/<id>.mid.edat (plain MIDI), .mogg, gen/<id>.milo_ps3 (our lipsync), .png_ps3 album art (native DXT1 encoder), and a generated songs.dta from song.ini.
• Xbox 360 CON — the same payload in a single STFS container (hash tables, volume descriptor), signable for retail hardware; YARG loads it unsigned. The inner .mid is byte-identical to the PS3 one — both builders share the same conversion chain.
• YARG / Clone Hero .sng — the modern single-file format, with the original chart data preserved (Phase Shift sysex, tap notes, LIPSYNC tracks).

The RB conversion chain ports what Onyx/Magma would do: open notes → green, 1×/2× bass pedal variants, crash-safety sanitizing (overlaps, unknown tracks), hand-map + init force markers, no-Magma fixups ([end], BEAT, drum [mix], unisons), a ≥6-beat lead-in pad on both MIDI and audio, and a preview window that starts 2 s before the first chorus when song.ini doesn't set one. A non-fatal validation gate checks the result against every RB3 crash class we know before it ships.

---

Install and use (prebuilt version)

1. Go to Releases and download Downcharter+.zip.
2. Unzip it into a folder of your choice.
3. Run Downcharter+.exe — no Python install needed.

In the app

1. Open… → pick the folder with your charts (subfolders included).
2. Toggle what to generate: Expert+, difficulties (Hard/Medium/Easy), venue, talkies, lipsync, hide in-game background.
3. Process folder — originals are backed up as .bak.mid / .bak.chart.
4. Convert — pick PS3 folder, CON or .sng and the pedal variant (1×/2×).
5. Changed your mind? Revert restores the originals.

---

Run from source

pip install -r requirements.txt
python main.py

Requires Python 3.10+. For GPU vocal separation install onnxruntime-directml (already listed in requirements.txt) — never together with plain onnxruntime.

---

Build the .exe

pip install -r requirements-build.txt
powershell -ExecutionPolicy Bypass -File build.ps1

Result:

• dist/Downcharter+/Downcharter+.exe — executable + dependencies (onedir)
• dist/Downcharter+.zip — ready to publish in Releases

Packaging uses PyInstaller via downcharter.spec, which bundles soundfile's libsndfile, the CMU pronunciation dictionary and the onnxruntime-directml runtime (DirectML.dll) for GPU vocal separation.

---

Structure

main.py              GUI (tkinter)
downcharter/         engine package
  processor.py         orchestrates the folder (process_folder / revert_folder)
  guitar.py guitar2.py guitar/bass/keys reduction
  guitar_handmap.py    force-HOPO/strum hand-position map (RB)
  drums.py             drums reduction + Expert+
  venue.py             camera, lights, post-proc, BEAT track, animations
  venue_director.py    song-level venue decisions (repetition, anchors, climax)
  cut_events.py        directed camera cuts (probabilistic, official-calibrated)
  audio.py             audio analysis (RMS / bands / voice activity / feel)
  separate.py          MDX-NET vocal separation (DirectML GPU / CPU)
  lipsync.py           phonemes → visemes → keyframes (mouth + facial)
  milo.py              native .milo builder (CharLipSync container)
  chart.py             reading .chart → .mid
  convert.py           RB conversion chain (open notes, sanitize, fixups, pad)
  ps3build.py          PS3/RPCS3 folder builder (+ songs.dta from song.ini)
  stfs.py              Xbox 360 CON/STFS packer
  sng.py               YARG/CH .sng packer
  validate.py          pre-pack RB3 crash-class checks (non-fatal)
  mogg.py              .mogg builder (stems → multichannel, 44.1 kHz)
  art.py               .png_ps3/.png_xbox album art (DXT1)
  midi_utils.py        tempo / MIDI event helpers
downcharter.spec     PyInstaller recipe
build.ps1            build script → dist/
tests/               pytest suite (185+ tests)