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
    CSS Filters

    CSS filter support recently landed within WebKit nightlies. CSS filters provide a method for modifying the rendering of a basic DOM element, image, or video. CSS filters allow for blurring, warping, and modifying the color intensity of elements. Let's have...

  • By
    5 Awesome New Mozilla Technologies You’ve Never Heard Of

    My trip to Mozilla Summit 2013 was incredible.  I've spent so much time focusing on my project that I had lost sight of all of the great work Mozillians were putting out.  MozSummit provided the perfect reminder of how brilliant my colleagues are and how much...

Incredible Demos

  • By
    Scrolling “Go To Top” Link Using Dojo

    One of the most popular code snippets of posted on my blog has been the scrolling "Go To Top" link snippet. The premise of the snippet is simple: once the user scrolls an element (usually the BODY element) past a given threshold, a "Go...

  • By
    MooTools TwitterGitter Plugin

    Everyone loves Twitter. Everyone loves MooTools. That's why everyone should love TwitterGitter, a MooTools plugin that retrieves a user's recent tweets and allows the user to format them however the user would like. TwitterGitter allows the user to choose the number of...

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!