How can I list video resolutions in youtube-dl while using it as a python module?

Question

Well, I can get the video formats directly by using this in terminal -

$ youtube-dl -F "some youtube url"

Output :

[youtube] Setting language
[youtube] P9pzm5b6FFY: Downloading webpage
[youtube] P9pzm5b6FFY: Downloading video info webpage
[youtube] P9pzm5b6FFY: Extracting video information
[info] Available formats for P9pzm5b6FFY:
format code extension resolution  note 
140         m4a       audio only  DASH audio , audio@128k (worst)
160         mp4       144p        DASH video , video only
133         mp4       240p        DASH video , video only
134         mp4       360p        DASH video , video only
135         mp4       480p        DASH video , video only
136         mp4       720p        DASH video , video only
17          3gp       176x144     
36          3gp       320x240     
5           flv       400x240     
43          webm      640x360     
18          mp4       640x360     
22          mp4       1280x720    (best)

but I want to use the same option while using youtube-dl as a module in python .

Right now I have to guess and specify the options for downloading as :

import youtube_dl

options = {
'format': 'bestaudio/best', # choice of quality
'extractaudio' : True,      # only keep the audio
'audioformat' : "mp3",      # convert to mp3 
'outtmpl': '%(id)s',        # name the file the ID of the video
'noplaylist' : True,        # only download single song, not playlist
}

with youtube_dl.YoutubeDL(options) as ydl:
    ydl.download(url)

I'm unable to know which format is available or not. but if I can get to list the available formats , then I can set those options accordingly .

Is there any way to use that "-F" switch inside python ?

Answer 1

If you use the listformats option to print the table to standard output, it won't download the video. For example:

import youtube_dl

options = {
    'format': 'bestaudio/best',  # choice of quality
    'extractaudio': True,        # only keep the audio
    'audioformat': "mp3",        # convert to mp3
    'outtmpl': '%(id)s',         # name the file the ID of the video
    'noplaylist': True,          # only download single song, not playlist
    'listformats': True,         # print a list of the formats to stdout and exit
}

with youtube_dl.YoutubeDL(options) as ydl:
    ydl.download(['http://www.youtube.com/watch?v=BaW_jenozKc'])

Answer 2

Look at the source code of youtube-dl, I see how do they list format of video

 def list_formats(self, info_dict):
    formats = info_dict.get('formats', [info_dict])
    table = [
        [f['format_id'], f['ext'], self.format_resolution(f), self._format_note(f)]
        for f in formats
        if f.get('preference') is None or f['preference'] >= -1000]
    if len(formats) > 1:
        table[-1][-1] += (' ' if table[-1][-1] else '') + '(best)'

    header_line = ['format code', 'extension', 'resolution', 'note']
    self.to_screen(
        '[info] Available formats for %s:\n%s' %
        (info_dict['id'], render_table(header_line, table)))

So is it very simple to get list the available formats by this way

ydl_opts = {}
with youtube_dl.YoutubeDL(ydl_opts) as ydl:
    meta = ydl.extract_info(
        'https://www.youtube.com/watch?v=9bZkp7q19f0', download=False) 
    formats = meta.get('formats', [meta])
for f in formats:
    print(f['ext'])