Download audio directly via SDK

[rajatjain]

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Question

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Is there a way to download only the audio corresponding to a youtube link via the SDK? I currently use the following code to download the video file and then use other converters to convert them to audio. I couldn't find a way in the source code to directly download in audio form.

def download_video(video_id, target_f):
    params = {
        'nocheckcertificate': True,
        'format': 'mp4',
        'ignoreerrors': True,
        'outtmpl': target_f,
    }

    yt = YoutubeDL(params=params)
    rc = 0
    try:
        rc = yt.download([video_id])
    except Exception as e:
        print("Couldn't download file with id %s. Exception: %s" % (video_id, str(e)))

    if rc != 0:
        return False
    return True

I tried putting in 'format': 'mp3' but it doesn't work.

[dstftw]

Read FAQ on format selection.

[rajatjain]

I tried the following code, but I'm unable to play it on iTunes, nor uses utilities like mutagen or eyed3. Both are unable to load the file.

def download_video(video_id, target_f):
    params = {
        'nocheckcertificate': True,
        'format': 'bestaudio/mpg3',
        'ignoreerrors': True,
        'outtmpl': target_f,
    }

    yt = YoutubeDL(params=params)
    rc = 0
    try:
        rc = yt.download([video_id])
    except Exception as e:
        print("Couldn't download file with id %s. Exception: %s" % (video_id, str(e)))

    if rc != 0:
        return False
    return True

I tried using 'format': 'bestaudio', bestaudio/mp3 but none of them work. I get the following error on the terminal.

$ afinfo ~/tmp/test.mp3
File:           /Users/rjain/tmp/test.mp3
Fail: AudioFileOpenURL failed