♫ AI charting for Clone Hero

Any song.
A playable chart. One paste.

Drop a YouTube link or an audio file. chartgen separates the recording, transcribes the real notes and writes a complete Clone Hero song folder — Expert through Easy, synced lyrics, star power, album art. On your own PC — about 90 seconds per song on a gaming GPU.

Free and open source (MIT). NVIDIA GPU recommended.

Features

Everything a chart needs, straight from the audio

No MIDI files, no charting experience. chartgen transcribes the song and shapes it into something that actually feels good under your fingers.

🎵

Paste a link, get a song

YouTube links, whole playlists, or local MP3, FLAC, WAV, OGG, Opus and M4A files. Batches queue up and chart one after another; already-charted songs are skipped.

🎹

Full difficulty ladder

Expert, Hard, Medium and Easy, each reduced the way human charters do it — calibrated against an 800-chart library of hand-made charts — plus a 0–6 difficulty rating for the song list.

🎤

Lyrics, in sync

Looked up on LRCLIB first and word-aligned to the isolated vocal, so lines land on the singer; when nobody has synced the song yet, the vocals are transcribed instead.

Star power & expression

Sustains from real note lengths, HOPOs, star power phrases, tap notes on synth and piano parts, solo markers, numbered practice sections — the details that make a chart feel charted, not generated.

🎧

Follows the instrument

Splits the song into six stems — vocals, drums, bass, guitar, piano, other — and tracks which one a charter would follow, so the chart plays the actual guitar or synth part instead of whatever is loudest.

🔒

Yours, locally

Separation, transcription and lyric alignment all run on your own PC — your audio never leaves it. There's even a phone-friendly web UI for queuing songs from the couch over your own network.

How it works

From speaker to fretboard in four steps

Feed it a song

Paste a YouTube link (or a whole playlist) into the app, or point it at audio files on disk. Artist and title come from the video or the file's tags.

It listens

The beat grid is detected, the recording is separated into stems, and Basic Pitch transcribes the real notes — pitch, timing, duration, polyphony — snapped to a grid that follows the song's tempo.

It charts like a charter

Notes become the five frets, riffs stay consistent every time they repeat, sustains ring where the music holds, taps and solos land where the lead is, and the Expert–Easy ladder is reduced tier by tier.

Drop it in Clone Hero

A finished song folder — notes.chart, audio, synced lyrics, album art from the video or the file's tags — lands straight in your Songs directory. Rescan and play.

Install

Two double-clicks and a coffee

Unzip, run the installer, run the app. It finds or installs Python, picks the right PyTorch build for your GPU and installs everything else.

# 1 — download the release zip and unzip it anywhere
chartgen-x.y.z.zip
# 2 — run the installer once (~3 GB of downloads, a few minutes)
install.bat
# 3 — open the app and chart something
chartgen.bat
Windows 10 / 11 NVIDIA GPU recommended — ~90 s per song vs ~20 min on CPU ~3 GB of dependencies, plus ~2.5 GB of models on the first charts Python 3.10–3.14 — installed for you if missing Clone Hero to play the results
♫ Ready when you are

Your library is one paste away

Every song you've ever wanted to play, charted while you warm up.