Convert webm to mp4

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There's an upcoming Mozilla trip to Hawaii on the cards and, in trying to be a good family man, I'm bringing my wife and two young sons.  Glutton for punishment?  Probably.  Anyways, I've been feverishly downloading cartoons from YouTube using youtube-dl to put onto our new iPad to keep my oldest son occupied during the long flight.

It seems as though YouTube preserves the original video format, since sometimes youtube-dl provides a webm and other times a mp4.  Since mp3s are iOS' best friend, I've needed to convert the webm files to mp4.  The following ffmpeg command will make that happen:

ffmpeg -i "Spider-Man.webm" -qscale 0 "Spider-Man.mp4"

The qscale 0 directive instructs ffmpeg not to adjust quality of the video during conversion.  And with this conversion I can now properly transfer the videos onto my iPad.

Check out my media tutorials for more magic when it comes to video, audio, and images.  You're sure to learn a few tricks along the way.

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Discussion

  1. Raph

    Hello,

    Have a look at this : https://www.onlinevideoconverter.com/firefox-addon

    This Grease adds a “convert” video to Youtube. Everything is processed on their server and it’s pretty fast !

  2. What about using the --list-formats argument with youtube-dl and download the MP4 that suits your needs?

  3. Jason Watkins

    Suggested code doesn’t work (10/22/17), Ubuntu 16.04.3 amd64

    “The encoder ‘aac’ is experimental but experimental codecs are not enabled, add ‘-strict -2’ if you want to use it.”

  4. It now says “Please use -q:a or -q:v, -qscale is ambiguous”.
    I guess -q:v 0 would be the new substitute.

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