gafotech/rhubarb-visemes

Dataset

Overview

This dataset contains 1,244 English speech alignment files with frame-level viseme labels produced via Rhubarb Lip Sync. Each alignment is expressed at a 16 kHz target sample rate with a 25 ms analysis window and 10 ms hop, and retains the relative path to the corresponding WAV used during generation.

Key figures:

• Total aligned duration: 14,280 s (3.97 h) across 1,244 clips
• Clip length: mean 11.48 s, median 9.15 s, min 0.84 s, max 38.21 s (5th-95th percentiles: 2.55-29.54 s)
• Frame count: 1,426,112 total (~1,146 per clip on average)
• Speakers: 52 synthetic voices with 22-25 clips each (mean 23.9 clips per speaker)
• Visemes: 9 classes (A, B, C, D, E, F, G, H, X) as detailed below

Viseme	Frames	Share
A	76,124	5.34%
B	630,457	44.21%
C	229,139	16.07%
D	49,494	3.47%
E	139,937	9.81%
F	93,707	6.57%
G	44,553	3.12%
H	31,499	2.21%
X (rest)	131,202	9.20%

The shortest aligned clip is Sarah_just_ask_me_1761254304995.wav (0.84 s); the longest is Thomas_A_labyrinthine_lexicon_unfurls_1761275991237.wav (38.21 s).

Directory Layout

.
  manifest.jsonl          # one JSON object per clip pointing to its alignment
  alignments/
    <clip>.alignment.json # frame-level labels and metadata
    <clip>.rhubarb.json   # raw mouthCue output from Rhubarb
  viseme_map.json         # viseme -> index mapping used in frame labels
  DATASET.md              # this document

manifest.jsonl is newline-delimited JSON. Each record exposes the relative path to its corresponding alignment file, for example:

{"alignment_path": "alignments/Adam_Beneath_the_glacier_s_glassy_g_1761276211449.alignment.json"}

Alignment Files

Every <clip>.alignment.json contains:

• audio_path: relative path to the WAV associated with the alignment
• sample_rate_target, win_length_ms, hop_length_ms: analysis parameters (16 kHz target, 25 ms window, 10 ms hop)
• viseme_list: ordered viseme labels; frame_labels stores integer indices into this list
• mouth_cues: the original intervals from Rhubarb (matching the companion <clip>.rhubarb.json)
• num_feature_frames: total frames in frame_labels
• frame_labels: per-frame viseme indices aligned to analysis hops (first frame begins at t=0)

Reconstructing the effective clip duration from metadata uses (num_feature_frames - 1) * hop + win (with hop and win expressed in seconds).

Generation Workflow

To regenerate alignments, use the script below:

1. Place WAV files under a source directory (e.g., audio/).
2. Run the script with matching arguments so it can locate the WAVs, call the Rhubarb binary, and write the JSON artifacts.
3. Inspect manifest.jsonl, alignments/, and viseme_map.json for the resulting outputs.

Example invocation:

python generate_dataset.py   --wavs_dir audio   --out_dir dataset   --rhubarb_path /path/to/rhubarb   --sr 16000 --win_length_ms 25 --hop_length_ms 10

Reference Script: generate_dataset.py

#!/usr/bin/env python3
"""
Generate frame-aligned viseme labels using Rhubarb Lip Sync.

For each WAV:
  1) Call Rhubarb to get mouthCues JSON: [{"start": float, "end": float, "value": str}, ...]
  2) Align to fixed feature hop (e.g., 10 ms) and window (e.g., 25 ms)
  3) Save per-file alignment and a manifest.jsonl for training

Example:
  python generate_dataset.py \
      --wavs_dir data/wavs \
      --out_dir data/dataset \
      --rhubarb_path rhubarb \
      --sr 16000 --win_length_ms 25 --hop_length_ms 10
"""

import argparse
import json
import math
import os
import subprocess
from pathlib import Path
from typing import List, Dict, Any

import numpy as np
import soundfile as sf  # <-- use soundfile for audio metadata (samplerate, frames, duration)

# === Adjust if your Rhubarb setup uses a different viseme set/order ===
VISEMES = ["A", "B", "C", "D", "E", "F", "G", "H", "X"]
VI2IDX = {v: i for i, v in enumerate(VISEMES)}

def find_wavs(root: Path) -> List[Path]:
    return sorted([p for p in root.rglob("*.wav") if p.is_file()])

def run_rhubarb(wav_path: Path, rhubarb_path: str, json_out: Path) -> None:
    json_out.parent.mkdir(parents=True, exist_ok=True)
    cmd = [rhubarb_path, "-f", "json", "-o", str(json_out), str(wav_path)]
    # You may add flags like: "--datacost 1.0" or "--extendedShapes" if desired.
    completed = subprocess.run(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, text=True)
    if completed.returncode != 0 or not json_out.exists():
        raise RuntimeError(
            f"Rhubarb failed for {wav_path}\nSTDOUT:\n{completed.stdout}\nSTDERR:\n{completed.stderr}"
        )

def load_mouth_cues(json_path: Path) -> List[Dict[str, Any]]:
    with open(json_path, "r", encoding="utf-8") as f:
        data = json.load(f)
    # Rhubarb JSON typically has {"mouthCues": [{"start":..,"end":..,"value":"A"}, ...]}
    cues = data["mouthCues"] if "mouthCues" in data else data
    return cues

def time_to_frame_idx(t_sec: float, hop_sec: float) -> int:
    # Frame index for frame whose "start" is at t_sec (STFT hop grid)
    # We align labels to frames whose start times are k * hop_sec
    return int(math.floor(t_sec / hop_sec + 1e-8))

def build_frame_labels_from_cues(
    cues: List[Dict[str, Any]],
    num_frames: int,
    hop_sec: float,
) -> np.ndarray:
    """
    Convert interval cues to frame labels aligned to frames starting at k*hop_sec.
    For each frame k, with frame time t = k*hop_sec, we assign the cue whose [start, end)
    contains t + epsilon. Default to 'X' if none covers.

    This yields a strictly causal alignment: label for frame k depends on cue at that time.
    """
    labels = np.full((num_frames,), fill_value=VI2IDX["X"], dtype=np.int64)
    # Build an efficient pointer sweep over sorted cues
    sorted_cues = sorted(cues, key=lambda c: c["start"])
    j = 0
    for k in range(num_frames):
        t = k * hop_sec  # start time of frame k
        # advance j while cue ends before t
        while j < len(sorted_cues) and sorted_cues[j].get("end", 1e9) <= t:
            j += 1
        # check current cue covers t
        if j < len(sorted_cues):
            c = sorted_cues[j]
            if c["start"] <= t < c.get("end", 1e9):
                vis = c["value"]
                if vis in VI2IDX:
                    labels[k] = VI2IDX[vis]
                else:
                    # Unknown label falls back to rest
                    labels[k] = VI2IDX["X"]
    return labels

def main():
    ap = argparse.ArgumentParser()
    ap.add_argument("--wavs_dir", type=str, required=True, help="Root directory containing WAV files")
    ap.add_argument("--out_dir", type=str, required=True, help="Output dataset directory")
    ap.add_argument("--rhubarb_path", type=str, default="rhubarb", help="Path to Rhubarb binary")
    ap.add_argument("--sr", type=int, default=16000, help="Target sample rate for consistent framing")
    ap.add_argument("--win_length_ms", type=float, default=25.0, help="STFT window length (ms)")
    ap.add_argument("--hop_length_ms", type=float, default=10.0, help="STFT hop length (ms)")
    ap.add_argument("--overwrite", action="store_true", help="Overwrite existing JSONs/labels")
    args = ap.parse_args()

    wavs_dir = Path(args.wavs_dir).resolve()
    out_dir = Path(args.out_dir).resolve()
    align_dir = out_dir / "alignments"
    align_dir.mkdir(parents=True, exist_ok=True)
    manifest_path = out_dir / "manifest.jsonl"

    win_length = int(round(args.win_length_ms * 1e-3 * args.sr))
    hop_length = int(round(args.hop_length_ms * 1e-3 * args.sr))
    hop_sec = hop_length / args.sr

    wav_paths = find_wavs(wavs_dir)
    if not wav_paths:
        raise SystemExit(f"No WAV files found under {wavs_dir}")

    if manifest_path.exists() and not args.overwrite:
        print(f"[INFO] {manifest_path} exists. Appending new entries (use --overwrite to recreate).")

    with open(manifest_path, "w" if args.overwrite else "a", encoding="utf-8") as man_f:
        for wav in wav_paths:
            rel_audio = os.path.relpath(wav, start=out_dir)
            base = wav.stem
            rhubarb_json = align_dir / f"{base}.rhubarb.json"
            alignment_json = align_dir / f"{base}.alignment.json"

            if (not rhubarb_json.exists()) or args.overwrite:
                print(f"[Rhubarb] {wav.name}")
                run_rhubarb(wav, args.rhubarb_path, rhubarb_json)
            else:
                print(f"[SKIP Rhubarb] {wav.name} (exists)")

            # Load audio duration and samplerate using soundfile (no full load)
            try:
                info = sf.info(str(wav))
            except RuntimeError as e:
                raise SystemExit(f"Failed to read audio info for {wav}: {e}")

            orig_sr = info.samplerate
            num_frames_audio = info.frames
            duration_sec = num_frames_audio / float(orig_sr)

            # Compute number of STFT frames at target SR/hop/window
            # Resampling does not change duration
            duration_at_target = duration_sec
            # Valid STFT frames start at t where t + win_length_sec <= duration
            win_sec = win_length / args.sr
            if duration_at_target < win_sec:
                print(f"[WARN] {wav.name} shorter than window; skipping.")
                continue
            max_k = math.floor((duration_at_target - win_sec) / hop_sec)
            num_feat_frames = max_k + 1

            cues = load_mouth_cues(rhubarb_json)
            labels = build_frame_labels_from_cues(cues, num_feat_frames, hop_sec)

            # Save alignment
            alignment_payload = {
                "audio_path": rel_audio.replace("\\", "/"),
                "sample_rate_target": args.sr,
                "win_length_ms": args.win_length_ms,
                "hop_length_ms": args.hop_length_ms,
                "n_visemes": len(VISEMES),
                "viseme_list": VISEMES,
                "mouth_cues": cues,
                "num_feature_frames": int(num_feat_frames),
                "frame_labels": labels.tolist(),
            }
            with open(alignment_json, "w", encoding="utf-8") as f:
                json.dump(alignment_payload, f, ensure_ascii=False, indent=2)

            # Write manifest line
            man_f.write(json.dumps({
                "alignment_path": os.path.relpath(alignment_json, start=out_dir).replace("\\", "/")
            }) + "\n")

    # Save viseme map for reference
    with open(out_dir / "viseme_map.json", "w", encoding="utf-8") as f:
        json.dump({v: i for i, v in enumerate(VISEMES)}, f, indent=2)
    print("\n[Done] Alignments and manifest created.")
    print(f"  - Manifest: {manifest_path}")
    print(f"  - Alignments: {align_dir}")

if __name__ == "__main__":
    main()