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
    39 Shirts – Leaving Mozilla

    In 2001 I had just graduated from a small town high school and headed off to a small town college. I found myself in the quaint computer lab where the substandard computers featured two browsers: Internet Explorer and Mozilla. It was this lab where I fell...

  • By
    Being a Dev Dad

    I get asked loads of questions every day but I'm always surprised that they're rarely questions about code or even tech -- many of the questions I get are more about non-dev stuff like what my office is like, what software I use, and oftentimes...

Incredible Demos

  • By
    Introducing MooTools ElementSpy

    One part of MooTools I love is the ease of implementing events within classes. Just add Events to your Implements array and you can fire events anywhere you want -- these events are extremely helpful. ScrollSpy and many other popular MooTools plugins would...

  • By
    MooTools CountDown Plugin

    There are numerous websites around the internet, RapidShare for example, that make you wait an allotted amount of time before presenting you with your reward. Using MooTools, I've created a CountDown plugin that allows you to easily implement a similar system. The MooTools JavaScript The CountDown class...

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!