verbanote-server/verbanote/process.py

import logging
import os
import re
import json
from dataclasses import dataclass
from pathlib import Path
from pyannote.audio import Pipeline
from pydub import AudioSegment
from whisper import Whisper

MILLISECONDS_TO_SPACE = 2000


@dataclass
class TxtTranscription:
    text: str
    file: Path


def diarize(audiofile: Path, pipeline: Pipeline, output_path: Path) -> Path:
    audiofile_prepended = _add_audio_silence(audiofile)

    logging.info(f"Beginning diarization of {audiofile}...")
    DIARIZE_FILE = {"uri": "not-important", "audio": audiofile_prepended}
    dz = pipeline(DIARIZE_FILE)

    out_file = Path.joinpath(output_path, "diarization.txt")
    with open(out_file, "w") as text_file:
        text_file.write(str(dz))
        logging.info(f"Created diarization in {out_file}.")

    return out_file


def transcribe(
    model: Whisper,
    diarized_groups: list,
    files_path: Path,
    lang: str = "en",
    word_timestamps: bool = True,
) -> None:
    for i in range(len(diarized_groups)):
        audio_f = Path.joinpath(files_path, f"{str(i)}.wav")
        json_f = Path.joinpath(files_path, f"{str(i)}.json")
        logging.info(f"Starting transcription of {str(audio_f)}...")
        result = model.transcribe(
            audio=str(audio_f), language=lang, word_timestamps=word_timestamps
        )
        with open(json_f, "w") as outfile:
            json.dump(result, outfile, indent=4)
            logging.info(f"Transcription written to {str(json_f)}.")


# TODO clean up this mess
def output_txt(diarized_groups: list, transcription_path: Path) -> TxtTranscription:
    txt = list("")
    gidx = -1
    for g in diarized_groups:
        shift = re.findall(r"[0-9]+:[0-9]+:[0-9]+\.[0-9]+", string=g[0])[0]
        shift = (
            _millisec(shift) - MILLISECONDS_TO_SPACE
        )  # the start time in the original video
        shift = max(shift, 0)

        gidx += 1

        fname = Path.joinpath(transcription_path, f"{str(gidx)}.json")
        with open(fname) as f:
            captions = json.load(f)["segments"]
            logging.info(f"Loaded {fname} for transcription...")

        if captions:
            speaker = g[0].split()[-1]
            
            txt.append(f"[{speaker}] ")
            for c in captions:
                txt.append(f"{c['text']}")
            txt.append("\n\n")

    output = "".join(txt)
    fname = Path.joinpath(transcription_path, "transcription_result.txt")
    with open(fname, "w", encoding="utf-8") as file:
        file.write(output)
        logging.info(f"Wrote transcription to output file {fname}.")
    return TxtTranscription(text=output, file=fname)


def save_diarized_audio_files(
    diarization: Path, audiofile: Path, output_path: Path
) -> list:
    groups = _group_speakers(diarization)
    _save_individual_audio_files(
        audiofile=audiofile, groups=groups, output_path=output_path
    )
    return groups


def _add_audio_silence(audiofile) -> Path:
    spacermilli = MILLISECONDS_TO_SPACE
    spacer = AudioSegment.silent(duration=spacermilli)
    audio = AudioSegment.from_wav(audiofile)
    audio = spacer.append(audio, crossfade=0)
    fname = Path.joinpath(Path(os.path.dirname(audiofile)), "interview_prepend.wav")
    audio.export(fname, format="wav")
    logging.info(f"Exported audiofile with silence prepended to {fname}.")

    return fname


def _save_individual_audio_files(
    audiofile: Path, groups: list[str], output_path: Path
) -> None:
    audio = AudioSegment.from_wav(audiofile)
    gidx = -1
    for g in groups:
        start = re.findall(r"[0-9]+:[0-9]+:[0-9]+\.[0-9]+", string=g[0])[0]
        end = re.findall(r"[0-9]+:[0-9]+:[0-9]+\.[0-9]+", string=g[-1])[1]
        start = _millisec(start)  # - spacermilli
        end = _millisec(end)  # - spacermilli
        gidx += 1
        fname = Path.joinpath(output_path, f"{str(gidx)}.wav")
        audio[start:end].export(fname, format="wav")
        logging.info(f"Exported audiopart {gidx} of {len(groups)} to {fname}.")


def _group_speakers(diarization_file: Path) -> list:
    dzs = open(diarization_file).read().splitlines()

    groups: list = []
    g = []
    lastend = 0

    for d in dzs:
        if g and (g[0].split()[-1] != d.split()[-1]):  # same speaker
            groups.append(g)
            g = []

        g.append(d)

        end = re.findall(r"[0-9]+:[0-9]+:[0-9]+\.[0-9]+", string=d)[1]
        end = _millisec(end)
        if lastend > end:  # segment engulfed by a previous segment
            groups.append(g)
            g = []
        else:
            lastend = end
    if g:
        groups.append(g)
    return groups


def _millisec(timeStr):
    spl = timeStr.split(":")
    s = (int)((int(spl[0]) * 60 * 60 + int(spl[1]) * 60 + float(spl[2])) * 1000)
    return s