Firefox 51: FLAC Audio Codec Support

Martin Brinkmann
Aug 30, 2016

Mozilla Firefox 51 will launch with support for the Free Lossless Audio Codec (FLAC) built-in to the web browser.

If you check browser support for various audio and video codecs, you will soon realize that support is a mess.

Not only is it different depending on the web browser that you are using, but it may also be different depending on the operating system.

Some formats, like mp3 or H.264, are supported by the majority of browsers while others, like FLAC or Ogg are not necessarily.

While you may not come across a single service or site that supports FLAC or OGG depending on what you do on the Internet, you will benefit from native integration if you do.

FLAC is for instance used by several high quality audio streaming services that offer lossless audio streams.

FLAC in Firefox

As far as FLAC is concerned, it is not supported by the majority of browsers. In fact, up to Firefox 51, it is not support by any browser with a noticeable market share.

firefox flac support

Mozilla is the first to introduce FLAC support. Starting with Firefox 51, FLAC support is built natively in Firefox.

Firefox 51 is the current version of the Nightly version of the Firefox browser. If you run it, you may listen to FLAC audio in Firefox already.

Up until now you had no option but to download the FLAC file, or get delivered a fallback format like mp3 instead if the service checked for support and noticed that it is not supported by the browser.

Some music services, Tidal needs to be mentioned in this regard, offer high quality playback using FLAC but only if the browser supports it.

Firefox 51 will be released to the stable channel on January 24, 2017 according to the Mozilla Firefox Release Schedule. Please note that the schedule or the integration of FLAC support may change, for instance if issues are encountered that require more development work on the feature.

You may check out the official bug listing over on Bugzilla to monitor its progress. (via Sören)

Now You: Are you excited about FLAC support in Firefox?

Firefox 51: FLAC Audio Codec Support
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Firefox 51: FLAC Audio Codec Support
Mozilla Firefox 51 will launch with support for the Free Lossless Audio Codec (FLAC) built-in to the web browser.
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  1. Dave said on September 2, 2016 at 1:17 pm

    I’m surprised that Mozilla hasn’t supported FLAC and codecs since the good-old-days. Seems negligent and corrosive to their cause (ex-cause).

    1. Kuromi said on October 2, 2016 at 9:57 pm

      Thats because in good-old-days they used half-own built-in decoders to play formats. Some time ago they adopted use of embedded, cut-down version of ffmpeg and all they needed to start support FLAC is just allow its decoding in that embedded ffmpeg. Its not like they didnt put any work on that, but there was no need to write own decoder or import new libs for that or to depend on system libs. Much easier now.

    2. anon said on September 2, 2016 at 3:41 pm

      FLAC is too heavy for general Internet use. They already have Opus.

  2. PD said on September 1, 2016 at 6:20 pm

    Wow :) Just when I had largely given up on Mozilla’s ability to remain relevant, they just *may* be starting to turn around years of dubious decisions.

    First some good signs (though IIRC nothing concrete) about webp and now FLAC. Grooovy!

    As for compat, let’s be sure to distinguish between codecs and containers. I’m no expert at all, but AFAIK Mastroska is open source. Hell it might even be *really* open source in that it’s available under one of the few (of many) open source licenses Mozilla supports. It’s the basis for webm but why redesign the wheel?

    Are there any limitations to mk(v|a|s|3D) that would prevent it becoming the universal container for browsers?

    As for codecs, h264 is the accepted incumbent despite it’s legal/political issues. Until a royalty-free, proven patent-free codec is developed and accepted, h264 has universal support.

    Opus is a great codec for anything from voice to music where it is competitive with mp3. It should be the universal audio standard in browsers. Toss in FLAC for lossless / higher definition audio and you’ve got a pretty good set of options.

  3. fena said on August 31, 2016 at 6:06 am

    I never play music inside a browser as my browser is usually closed.

    1. mikef90000 said on September 1, 2016 at 4:21 am

      I agree, if possible I play video or audio externally with VLC. Same with viewing PDFs, the built in viewer sucks. Trying to disable all of this dynamic application stuff is like playing whack-a-mole!

      1. PD said on September 1, 2016 at 6:27 pm

        I find the built-in PDF viewer in Firefox to be more than adequate. I hugely prefer it over the enormously bloated Adobe version, especially when it’s shoehorned into the browser via a security-nightmare plugin.

        Playing music as a end-user is not the only use case for audio codecs. imagine a website wants to offer music for users in smaller, compressed file sizes on, in particular, mobile networks that tend to be slower. But the same site wants to give users the right to choose lossless versions if they’re willing/able to wait for the slower download. But the users are never too sure if the lossless version is worthwhile. No problem with browser FLAC support … build some UI into your website allowing users to preview inline part of the FLAC file, letting them compare with their own ears whether the difference is worthwhile.

  4. Anon-Not-Anon said on August 31, 2016 at 2:04 am
  5. anon said on August 30, 2016 at 10:47 pm
    1. Joar said on October 31, 2016 at 1:50 pm

      I don’t get the comments about Chrome/Chromium here.
      I daily use FLAC streaming on Chrome fine (from TIDAL). In fact this is the only reason I have Chrome installed on my system – I’d prefer using Firefox so I’m happy about these news about Firefox 51 supporting it.
      My system is currently Chrome 52.0.2743.82 (64-bit) on Arch Linux, streaming to a Cambride DAC on USB.

    2. Fx0 said on August 31, 2016 at 2:01 pm

      I would not say “it’s also coming to Chromium” because it’s totally unclear. It’s a ticket about FLAC support with no developer activity since almost 1 1/2 years. ;)

      1. anon_not_anon said on August 31, 2016 at 10:22 pm

        Comment 44 by kea…, Yesterday (42 hours ago)
        I have submitted a new issue. To those following this issue, please star it but avoid commenting with “bump” since it’s a brand new issue. Feel free to leave well-written comments showing your support for it, however.
        Comment 45 by, Yesterday (40 hours ago)
        Issue 642219 has been merged into this issue.

  6. Anonymous said on August 30, 2016 at 9:35 pm

    “FLAC is for instance used by several high quality audio streaming services”

    Probably paying services i guess? > “Browsing our HQ audio streaming site with Firefox is highly recommended, if that is the case you will get an instant promotion of about 30%, 29% to the Mozilla Corp, 1% for the Pandas they can learn music during reproduction”.

    1. PD said on September 1, 2016 at 6:29 pm

      Some people still believe artists deserve to be paid for their music. If you don’t, so be it.

  7. b said on August 30, 2016 at 9:04 pm

    great news. looking forward to january 2017

  8. Jamie said on August 30, 2016 at 10:44 am

    I don’t think it’s necessary. I don’t want to auto load 100mb audio everytime

    1. Tom said on August 30, 2016 at 1:50 pm

      No need to worry, you won’t load it unless you choose to. Website owners and server providers want to save bandwidth even more than you do.

      If you want to complain about unnecessary, there’s uncompressed WAV/PCM support. Now _that_ is a real waste of bandwidth (of course, WAV is very rarely used, just like FLAC will be).

  9. Tony said on August 30, 2016 at 10:28 am

    This could provide a big boost to the adoption of FLAC. Good for Mozilla.

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