处理从 niconico 抓包获取的 .ts 分片文件。

nicotscat.py

from pathlib import Path
import argparse

parser = argparse.ArgumentParser()
parser.add_argument('--root', type=Path, default='.')
parser.add_argument('--ext', type=str, default='.ts')
parser.add_argument('--record', '--archive', '--recording', action='store_true', default=False)
parser.add_argument('--out-m3u8', type=Path, default=Path('./list.m3u8'))
args = parser.parse_args()

ROOT = Path(r'.')
M3U8_TEMPLATE = '''#EXTM3U
#EXT-X-VERSION:3
#EXT-X-TARGETDURATION:1.500
{fragments}
#EXT-X-ENDLIST'''


def main():
    fragments = []
    divable_by_5000 = 0

    for path in ROOT.glob(f'**/*{args.ext}'):
        try:
            num = int(path.stem)
        except ValueError:
            continue

        if num % 5000 == 0:
            divable_by_5000 += 1

        fragments.append(num)

    if divable_by_5000 > len(fragments) * 0.9 and not args.record:
        print(f'检测到 {divable_by_5000} 个文件名为 5000 的倍数，这可能是录播文件。')
        print(f'如果是录播文件，请使用 --record 参数。\n')
        exit(1)

    fragments.sort()

    if len(fragments) == 0:
        print('找不到任何文件名为数字的 ts 文件，退出。\n')
        exit(1)

    lack_fragments = []

    diff = 5000 if args.record else 1

    for i in range(1, len(fragments)):
        if fragments[i] != fragments[i - 1] + diff:
            for lacked_index in range(fragments[i - 1] + diff, fragments[i], diff):
                lack_fragments.append(lacked_index)

    m3u8_fragments = '\n'.join(
        f'#EXTINF:1.500,\n{num}{args.ext}' for num in fragments)

    with (ROOT / 'list.m3u8').open('w', encoding='utf-8') as f:
        f.write(M3U8_TEMPLATE.format(fragments=m3u8_fragments))

    print(f'已生成 m3u8 分片列表文件。')
    print(f'最小值：{min(fragments)}，最大值：{max(fragments)}，缺失分片个数：{len(lack_fragments)}')
    print(f'\n')
    if len(lack_fragments) > 0:
        print(f'缺失分片列表：\n{", ".join(str(x) for x in lack_fragments)}\n')
    else:
        print(f'没有缺失分片。\n')

    print(f'使用如下命令合成 ts：')
    print(f'    ffmpeg {"-allowed_extensions ALL " if args.ext != ".ts" else ""}-i list.m3u8 -c copy output.mp4\n')


if __name__ == '__main__':
    main()