Choosing output file name in Python API

[Zulko]

Hi there, I am trying to download a video using the python API:

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

I can't figure what to put in the options to be able to set the output filename. Am I missing something obvious ? Thanks in advance.

[phihag]

Use the outtmpl parameter:

from __future__ import unicode_literals
import youtube_dl
ydl_opts = {
    'outtmpl': '/tmp/foo_%(title)s-%(id)s.%(ext)s'
}
with youtube_dl.YoutubeDL(ydl_opts) as ydl:
    ydl.download(['http://www.youtube.com/watch?v=BaW_jenozKc'])

[Zulko]

Thanks, but that doesn't work for me. To be more precise: at the command line i can write

youtube-dl Nh11A41klL4 pigs.mp4

In the Python version I did not manage to force pigs.mp4 as an outputname . If my name is not a proper template like foo_%(title)s-%(id)s.%(ext)s I get an assertion error. Any idea ? Thanks for your time.

[phihag]

youtube-dl Nh11A41klL4 pigs.mp4 will try to download pigs.mp4:

$ youtube-dl Nh11A41klL4 pigs.mp4
[youtube] Nh11A41klL4: Downloading webpage
[youtube] Nh11A41klL4: Extracting video information
[youtube] Nh11A41klL4: Downloading DASH manifest
[download] Destination: Looney Tunes - Pigs in a Polka 1943-Nh11A41klL4.mp4
[download] 100% of 36.02MiB in 00:04
ERROR: u'pigs.mp4' is not a valid URL. Set --default-search "ytsearch" (or run  youtube-dl "ytsearch:pigs.mp4" ) to search YouTube

Please do post the error. Without it, we cannot help you.

[phihag]

One more note: If you are still using Python 2.x, you must make sure to pass in unicode and not byte objects. The simplest way to do this is to add from __future__ import unicode_literals to the top of your file.

[Zulko]

Sorry for that, I meant

youtube-dl Nh11A41klL4 -o pigs.mp4

This command works and downloads the video as pig.mp4. Then, when I try the Python API version with this code:

import youtube_dl
def download_webfile(url, filename=None, **ydl_opts):
    if filename is not None:
        ydl_opts["outtmpl"]= filename
    with youtube_dl.YoutubeDL(ydl_opts) as ydl:
        ydl.download([url])

# This will work and import the video under its youtube name
#download_webfile("Nh11A41klL4")

# When I try to specify a filename using "outtmpl" it crashes with Assertion Error
download_webfile("Nh11A41klL4", "pigs.mp4")

I get this error. Importing unicode_literals did not solve the problem.

[phihag]

Can you post the error you get when you add the from __future__ import unicode_literals line?

[Zulko]

Wait, it works ! My mistake with unicode_literal was that I imported it in the file where my function download_webfile is defined, while I should have imported it in the file where I call download_webfile("Nh11A41klL4", "pigs.mp4") (dumb me).

Also, in python2 simply writing ydl_opts["outtmpl"]= unicode(filename) seems to solve the problem.

I believe it's solved. Thanks for your time !

[BiTinerary]

ydl_opts = {'outtmpl' : unicode(customName)}
    with youtube_dl.YoutubeDL(ydl_opts) as ydl:
        ydl.download([URLofVideo])

In terms of renaming the downloaded video, this also worked for me.