Convert webm to mp4

By  on  

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.

Recent Features

  • By
    Serving Fonts from CDN

    For maximum performance, we all know we must put our assets on CDN (another domain).  Along with those assets are custom web fonts.  Unfortunately custom web fonts via CDN (or any cross-domain font request) don't work in Firefox or Internet Explorer (correctly so, by spec) though...

  • By
    Create a CSS Cube

    CSS cubes really showcase what CSS has become over the years, evolving from simple color and dimension directives to a language capable of creating deep, creative visuals.  Add animation and you've got something really neat.  Unfortunately each CSS cube tutorial I've read is a bit...

Incredible Demos

  • By
    HTML5 download Attribute

    I tend to get caught up on the JavaScript side of the HTML5 revolution, and can you blame me?  HTML5 gives us awesome "big" stuff like WebSockets, Web Workers, History, Storage and little helpers like the Element classList collection.  There are, however, smaller features in...

  • By
    CSS content and attr

    CSS is becoming more and more powerful but in the sense that it allows us to do the little things easily.  There have been larger features added like transitions, animations, and transforms, but one feature that goes under the radar is generated content.  You saw a...

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.

Wrap your code in <pre class="{language}"></pre> tags, link to a GitHub gist, JSFiddle fiddle, or CodePen pen to embed!