How to add codec to the filename

[davidhedlund]

youtube-dl -f 251 https://www.youtube.com/watch?v=nhNUlAudx8E -o "%(title)s.%(format_id)s.%(ext)s"

That will download the file as

Electric Universe - Freedom.251.webm

However, "251" will cause confusion as people do not know that it is "Opus". I would like it add the actual codec like this:

Electric Universe - Freedom.opus.webm

How do I do that?

[phihag]

Use the -o option to set an output template, and include %(acodec)s for the audio codec:

$ youtube-dl -f 251 nhNUlAudx8E -o "%(title)s-%(id)s.%(acodec)s.%(ext)s" --get-filename
Electric Universe - Freedom-nhNUlAudx8E.opus.webm

For more information, refer to the documentation.

[davidhedlund]

@phihag Thank you.

[davidhedlund]

@phihag Why do

youtube-dl -x -f 251 nhNUlAudx8E

give

Electric Universe - Freedom-nhNUlAudx8E.mp3

rather than this?

Electric Universe - Freedom-nhNUlAudx8E.opus

The solution was

youtube-dl -x --audio-format opus --audio-quality 0 nhNUlAudx8E

However, this is really what I'm requesting with -f 251 which is confusing.

[phihag]

The default --audio-format happens to be mp3 in some cases.

If you want opus, say so, and don't include -f at all, as you seem to have done. -f 251 literally means: pick format 251 - nothing more, nothing less. It's better to describe the desired result and let youtube-dl figure out how to get there.

[davidhedlund]

@phihag

youtube-dl -F nhNUlAudx8E | grep 251
251 webm audio only DASH audio 138k , opus @160k, 6.02MiB

Format 251 is webm with opus, not webm with mp3.

[phihag]

Indeed, but that's all just the video format (although this happens to be one video format that contains audio only). --audio-format controls the behavior of --extract-audio which advises youtube-dl to extract an audio file from the video file.

[yan12125]

youtube-dl -x -f 251 nhNUlAudx8E works as expected for me:

$ youtube-dl -v -x -f 251 nhNUlAudx8E -o "%(title)s-%(id)s.%(acodec)s.%(ext)s" --get-filename
[debug] System config: []
[debug] User config: []
[debug] Command-line args: ['-v', '-x', '-f', '251', 'nhNUlAudx8E', '-o', '%(title)s-%(id)s.%(acodec)s.%(ext)s', '--get-filename']
[debug] Encodings: locale UTF-8, fs utf-8, out UTF-8, pref UTF-8
[debug] youtube-dl version 2016.07.28
[debug] Git HEAD: 0cacae2
[debug] Python version 3.5.2 - Linux-4.6.5-1-ARCH-x86_64-with-arch
[debug] exe versions: ffmpeg 3.1.1, ffprobe 3.1.1, rtmpdump 2.4
[debug] Proxy map: {}
Electric Universe - Freedom-nhNUlAudx8E.opus.webm