audio_split.py

import os
from pydub import silence, AudioSegment

MIN_SILENCE_LEN = 300
MIN_DURATION = 300
DEBUG = 0


def read_audio(audio_path):
    audio = AudioSegment.from_file(audio_path)
    audio = audio.set_channels(1)

    return audio


def concatenate_edges(raw_interval):
    edges = [raw_interval[0]]

    # concatenate two edges if the interval btw them is too short
    for idx in range(1, len(raw_interval) - 1):
        cur_start = raw_interval[idx][0]
        prev_end = edges[-1][1]

        if cur_start - prev_end < MIN_SILENCE_LEN:
            edges[-1][1] = raw_interval[idx][1]
        else:
            edges.append(raw_interval[idx])

    return edges


def get_rid_of_short_intervals(edges):
    intervals = []

    for idx in range(len(edges)):
        if edges[idx][1]-edges[idx][0] > MIN_DURATION:
            intervals.append(edges[idx])

    return intervals


def split_on_silence_with_pydub(
        audio_path, skip_idx=0, out_ext="wav",
        silence_thresh=-40, silence_chunk_len=100, keep_silence=100):

    filename = os.path.basename(audio_path).split('.', 1)[0]
    audio = read_audio(audio_path)

    not_silence_ranges = silence.detect_nonsilent(
        audio, min_silence_len=silence_chunk_len,
        silence_thresh=silence_thresh)

    edges = concatenate_edges(not_silence_ranges)
    intervals = get_rid_of_short_intervals(edges)

    # Save audio files
    audio_paths = []

    for idx, (start_idx, end_idx) in enumerate(intervals[skip_idx:]):
        start_idx = max(0, start_idx - keep_silence)
        end_idx += keep_silence

        target_audio_path = "{}/pre_audio/{}.{:04d}.{}".format(os.path.dirname(audio_path), filename, idx, out_ext)
        segment = audio[start_idx:end_idx]
        segment.export(target_audio_path, out_ext)
        audio_paths.append(target_audio_path)

    return audio_paths, intervals


if __name__ == "__main__":
    audio_list, intervals = split_on_silence_with_pydub("./pre_audio/androcles-shorter.mp3")