Files
lux/modules/capabilities/_diarize-transcript.py
T
2026-09-17 16:44:22 +02:00

119 lines
3.3 KiB
Python

import argparse
import json
import re
from dataclasses import dataclass
from itertools import groupby
from pathlib import Path
@dataclass(frozen=True)
class Turn:
start: float
end: float
speaker: str
@dataclass
class Token:
start: float
end: float
text: str
def load_tokens(path: Path) -> list[Token]:
with path.open(encoding="utf-8") as file:
transcript = json.load(file)
tokens: list[Token] = []
pending = ""
# Whisper reserves all IDs from end-of-text onward for control tokens.
end_of_text = 50256 + int(transcript["model"]["multilingual"])
for segment in transcript["transcription"]:
for raw_token in segment["tokens"]:
if raw_token["id"] >= end_of_text:
continue
text = raw_token["text"]
offsets = raw_token.get("offsets")
if not text:
continue
if offsets is None:
if tokens:
tokens[-1].text += text
else:
pending += text
continue
tokens.append(
Token(offsets["from"] / 1000, offsets["to"] / 1000, pending + text)
)
pending = ""
if not tokens:
raise ValueError("Whisper produced no timed text")
return tokens
def load_turns(audio: Path, model: Path) -> list[Turn]:
from pyannote.audio import Pipeline
pipeline = Pipeline.from_pretrained(model)
result = pipeline(str(audio))
turns = [
Turn(segment.start, segment.end, speaker)
for segment, _, speaker in result.exclusive_speaker_diarization.itertracks(
yield_label=True
)
]
if not turns:
raise RuntimeError("Pyannote detected no speech")
return turns
def token_speaker(token: Token, turns: list[Turn]) -> str:
midpoint = (token.start + token.end) / 2
def rank(turn: Turn) -> tuple[float, float]:
overlap = max(0.0, min(token.end, turn.end) - max(token.start, turn.start))
distance = max(turn.start - midpoint, midpoint - turn.end, 0.0)
return overlap, -distance
return max(turns, key=rank).speaker
def render(tokens: list[Token], turns: list[Turn]) -> str:
speaker_numbers: dict[str, int] = {}
rendered = []
for speaker, group in groupby(
tokens, key=lambda token: token_speaker(token, turns)
):
number = speaker_numbers.setdefault(speaker, len(speaker_numbers) + 1)
text = "".join(token.text for token in group)
text = re.sub(r"\s+", " ", text).strip()
if text:
rendered.append(f"**Speaker {number}:**\n\n{text}")
if not rendered:
raise ValueError("Whisper produced no transcript text")
return "\n\n".join(rendered) + "\n"
def main() -> None:
parser = argparse.ArgumentParser()
parser.add_argument("--audio", required=True, type=Path)
parser.add_argument("--model", required=True, type=Path)
parser.add_argument("--transcript", required=True, type=Path)
parser.add_argument("--output", required=True, type=Path)
args = parser.parse_args()
tokens = load_tokens(args.transcript)
turns = load_turns(args.audio, args.model)
args.output.write_text(render(tokens, turns), encoding="utf-8")
if __name__ == "__main__":
main()