pytube download script

download.py

#!/usr/bin/env python3
import argparse
from pytube import YouTube


def download(url):
    def progress_callback(stream, chunk, file_handle, bytes_remaining):
        # this function is called by download process... do not call directly!
        total_size = stream.filesize
        downloaded_size = total_size - bytes_remaining
        progress = downloaded_size / total_size * 100
        print('{:.3f}% downloaded'.format(progress), end='\r')

    def complete_callback(stream, file_handle):
        # this function is called by download process... do not call directly!
        # do nothing but print newline
        print()

    yt = YouTube(url, on_progress_callback=progress_callback, on_complete_callback=complete_callback)
    print(yt.title)

    # video
    # pytube's `order_by('resolution')` sorts streams by lexicographical order. do not use it.
    video_progressive = max(yt.streams.filter(progressive=True).all(), key=lambda x: int(x.resolution[:-1]))
    video_adaptive = max(yt.streams.filter(only_video=True).all(), key=lambda x: int(x.resolution[:-1]))

    if video_progressive and video_adaptive:
        # compare two resolution
        progressive_res = int(video_progressive.resolution[:-1])
        adaptive_res = int(video_adaptive.resolution[:-1])

        if progressive_res >= adaptive_res:
            print('Download progressive video codec={vid.video_codec} res={vid.resolution}, audio codec={vid.audio_codec}'.format(vid=video_progressive))
            video_progressive.download(filename=yt.title+'_progressive')

    if video_adaptive:
        print('Download video codec={vid.video_codec} res={vid.resolution}'.format(vid=video_adaptive))
        video_adaptive.download(filename=yt.title+'_video')

    # audio
    audio_adaptive = None
    if video_adaptive and video_adaptive.subtype == 'mp4':
        audio_adaptive = yt.streams.filter(only_audio=True, file_extension='mp4').order_by('bitrate').desc().first()
    else:
        audio_adaptive = yt.streams.filter(only_audio=True, audio_codec='vorbis').order_by('bitrate').desc().first()
    
    if audio_adaptive is None:
        # grab any audio tracks
        audio_adaptive = yt.streams.filter(only_audio=True).order_by('bitrate').desc().first()

    if audio_adaptive:
        print('Download audio codec={aud.audio_codec} bitrate={aud.bitrate}'.format(aud=audio_adaptive))
        audio_adaptive.download(filename=yt.title+'_audio')
    
    if audio_adaptive and audio_adaptive.subtype == 'mp4':
        audio_alternative = yt.streams.filter(only_audio=True, audio_codec='vorbis').order_by('bitrate').desc().first()
        if audio_alternative:
            print('Download audio codec={aud.audio_codec} bitrate={aud.bitrate}'.format(aud=audio_alternative))
            audio_alternative.download(filename=yt.title+'_vorbis')


def main():
    # argument parser
    parser = argparse.ArgumentParser(description='YouTube Download')
    parser.add_argument('urls', nargs='+', metavar='URL')
    args = parser.parse_args()

    print(args.urls)
    for url in args.urls:
        download(url)


if __name__ == '__main__':
    main()