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Apple's Lossless Audio Codec (ALAC) Now Open Source

Posted by samzenpus on from the free-music dept.

Revotron writes "Apple has released the full source to their Apple Lossless Audio Codec under the Apache license. ALAC was developed by Apple and deployed on all of its platforms and devices over the last 10 years. Could the release of the ALAC source code mark a possible first step in opening up more of the iOS platform?"

27 of 526 comments (clear)

  1. Why not... by Lanteran · · Score: 5, Insightful

    ...just use FLAC?

    --
    "People don't want to learn linux" hasn't been a valid excuse since '03.
    1. Re:Why not... by Anonymous Coward · · Score: 3, Funny

      Because FLAC is for cyber-communists.

    2. Re:Why not... by Tr3vin · · Score: 5, Informative

      If you use and iPod, FLAC isn't going to play.

    3. Re:Why not... by BasilBrush · · Score: 5, Informative

      It seems like FLAC has a slight compression edge

      Not according to this table.
      http://wiki.hydrogenaudio.org/index.php?title=Lossless_comparison

      Note for the compression ratio, smaller percentage is better. ALAC is slightly better than FLAC. But it's so marginal it makes no difference.

    4. Re:Why not... by NiceGeek · · Score: 3, Informative

      You *might* have a point about the connectors, but then again, that applies to many, many electronics manufacturers. You are *not* locked to iTunes, neither for the store or for updating your iPod. Spin your FUD elsewhere
      .

    5. Re:Why not... by Yvan256 · · Score: 5, Interesting

      And going with a locked-down, Microsoft-created format is better how, exactly? And iPod/iTunes was compatible with MP3 from day one. I don't know any non-nerd who uses Vorbis or FLAC.

      And at least Apple had the insight of going with AAC, developed by Dolby, instead of trying to re-create the wheel like Microsoft always does.

      Take a screenshot with Windows: Microsoft BMP. Like there wasn't enough graphic formats at the time.
      Take a screenshot on Mac OS X: 24-bit PNG (Open format which already existed).

      Default audio format with Windows: Microsoft WMA. MP3 and VQF were available at the time.
      Default audio format with Apple: AAC (developed by Dolby)

    6. Re:Why not... by DJRumpy · · Score: 4, Informative

      No, the connectors that interface with the PC are standard USB or Firewire. This is FUD. Any MP3, AAC, AIFF, or WAV will work with an iPod, iPhone, iPad, etc. You are NOT required to use iTunes either. There are a multitude of alternatives (http://www.sourceforge.net). Even if you choose to use iTunes, it can be set to use MP3 if you don't like AAC.

      I mean seriously, 2 seconds on Google would net you a decent list of alternatives without any effort at all:

      http://www.pcworld.com/article/227348/apple_itunes_alternatives_make_managing_your_music_easy.html

      Frankly I think some of the folks on here are so Anti-Apple they dont' even bother to verify what they post anymore. They just regurge the same bile that seems all too common in here these days.

    7. Re:Why not... by Moridineas · · Score: 3, Insightful

      Honestly, who gives a shit if the connector on one end isn't a mini-usb. iPhones/iPods/iPads support USB bus connections. Every hotel I've stayed at in the last 2-3 years just about has had an alarm clock with an Apple dock connector, so, I'm actually getting more utility out of the proprietary connector than you are with a standard (I've never even seen an alarm clock that has a USB plug). But again, who really gives a shit? You can get a new cable for like $3. I can see getting one's panties in a twist over DRM (though gone for years from music) or what not, but a cord--that is probably for most people even more ubiquitous than mini/micro-USB? Sheesh.

    8. Re:Why not... by Moridineas · · Score: 3, Interesting

      I said probably because I obviously don't have any numbers to back my statements up, and I doubt they exist. I do think people--in general--run into iDevice dock connector devices far more often than devices that suport, well, anything else.

      There have been over 300 million iPods alone sold. 110 million plus iphones. 40 million iphones. Every single one uses the same dock connector. It may not be a standard, but it's pretty ubiquitous. Many cars have iPod dock options. As I said in my other post, almost every single hotel I've stayed at in the 2-3 years has had an iDock alarm clock (Marriotts mostly, FWIW). In terms of 3rd party device for support non-iDevices, does such a thing even exist?

    9. Re:Why not... by Moridineas · · Score: 4, Insightful

      You're right, I think a lot of the whining done here is bizarre.

      The Microsoft tax doesn't affect me; I choose to no longer use Microsoft products.

      The Apple tax and Apple walled garden affects me; I choose to use Apple products.

      Nobody is MAKING me do either thing. I, as an individual, can make decisions. It's obvious that a very large percentage of the human race doesn't like it when other people make contrary decisions.

      Why does someone--in this case "nashv"--care what product I use ("Ok , ok, I couldn't resist showing my distaste for those infernal locked down devices.")? Why does he care what type of cord a product he doesn't like uses? It's just mere human tribalism and partisanship. It's an "if you're not with me, you're against me" mentality. Beyond my that, just how unbelievably minor and petty, that so many people seem to need to come online and bash somebody's choice of cell phone or music device.

    10. Re:Why not... by bemymonkey · · Score: 3, Insightful

      Isn't that a reason NOT to use an iPod? Jeeze, stop buying crippled crap.

    11. Re:Why not... by dabadab · · Score: 4, Informative

      You are NOT required to use iTunes either. There are a multitude of alternatives

      This is not true, at least not for everything. All the alternatives rely on libgpod and it does not support the newer devices:
      "This release has support for all iPod models except the iPod Nano 6g (the touch one). Most non-jailbroken iOS devices (iPod Touch, iPhone) are also supported with the notable exception of the iPad and the iPhone/iPod Touch 4 which are only supported as read-only devices."

      Maybe you should verify what you say by googling for two seconds ;-)

      --
      Real life is overrated.
    12. Re:Why not... by steveha · · Score: 4, Informative

      AAC, developed by Dolby,

      Incorrect. AAC was developed in an MPEG standards process. It was mostly based on the work of James D. Johnston ("JJ") who worked for Bell Labs at the time.

      Basically, AAC started out as "PAC", which was JJ Johnston's follow-on to MP3. See slide 5 of this presentation (PowerPoint format, sorry, but LibreOffice Impress does open it):

      http://www.aes.org/sections/pnw/ppt/jj/pac_history.ppt

      JJ was quite unhappy with some of the compromised in MP3, compromises that were forced upon him by the standards process. PAC was his improved coder, which didn't include the parts he didn't like from MP3. PAC won the "bake-off" between prospective coders; it was enough better than the others that MPEG reconsidered their "backward compatible" strategy and decided to go ahead with "non-backward compatible" (NBC).

      The Wikipedia page on AAC makes strangely little mention of JJ Johnston and his contributions, but if you look at the footnotes you will notice "J D Johnston" being frequently mentioned, especially in conjunction with the patents involved.

      JJ is a good guy who deserves more credit than he gets on Wikipedia.

      steveha

      --
      lf(1): it's like ls(1) but sorts filenames by extension, tersely
    13. Re:Why not... by teh+kurisu · · Score: 4, Informative

      A clock with a USB port is by necessity a much more complex device than a clock with an Apple dock connector. Aside from having to implement the USB mass storage specification, it also has to have its own audio hardware. Your MP3 player is just acting as a glorified hard drive, and the clock is doing all the work. Also, if you're using any audio functionality that isn't exposed over mass storage, or isn't supported by the clock's hardware, then it won't work.

      With an Apple dock connector, the clock only has to use the analogue signal from the dock connector's line out, and pass it straight to the amplifier. It will probably also use a subset of the Apple Accessory Protocol to provide audio controls - this works across a dedicated set of pins on the connector and is pretty simple to implement. With a dock connector, your iPod is doing all the work, so your clock is cheaper and with fewer compatibility concerns.

      It's no surprise that most manufacturers have gone down the route of including a dock connector at the expense of USB. The dock connector is supported by the majority (or certainly a large minority) of audio playing devices in users' hands, it's simpler to implement, and there won't be the questions over compatibility that would plague the equivalent USB device. It's not rudeness, it's good business sense.

      Most clocks like this will also have a standard 3.5 mm minijack line-in for compatibility with other devices anyway. Mine does.

      And yes, I'm still annoyed that Intel didn't think about implementing and standardising extra functionality such as this when it was designing USB 3.0. The time was right.

    14. Re:Why not... by am+2k · · Score: 4, Informative

      I don't know any non-nerd who uses Vorbis or FLAC.

      Actually, a lot of non-nerds do, they just don't know it. Nearly all games (on the consoles and PC/Mac) use ogg vorbis for the background music. The reason is that it doesn't cost anything (as opposed to mp3), and the game has to supply the music files and the decoder to play them anyways.

    15. Re:Why not... by makomk · · Score: 3, Informative

      You are NOT required to use iTunes either.

      On all modern iPods, you need a secret cryptographic key to be able to add or remove tracks that's specific to your iPod's serial number. Some very hard-working hackers have managed to reverse-engineer the algorithm in iTunes to generate keys from serial numbers, but after the first time they did this Apple changed the algorithm and threw all their code-obfuscation and anti-debugging techniques that they'd developed for the iTunes DRM into protecting it. They managed to deobfuscate it and get the new key generation algorithm, though Apple used legal threats to take down all info on how they did it so the next time Apple change their algorithm you'd better hope the original people are still around and willing.

      (Oh, and for iPhone and iPod Touch they go to a fair bit of effort to change the encryption and authentication keys with every major iOS update, if not more often.)

    16. Re:Why not... by Dr.Dubious+DDQ · · Score: 3, Interesting

      Vorbis is also the audio codec for Google's legally-free "webm" video format, which is vp8 video and vorbis audio in a specific form of Matroska container (instead of Ogg, which seems to invoke hatred among some programmers where Matroska apparently doesn't). Hypothetically, you can make a standards-complaint audio-only webm file to use in place of Ogg Vorbis for anything that supports webm and get the superior-to-mp3 Vorbis quality sound in anything that supports webm - mostly web browsers and at least some Android devices.

      (ALL android-based devices support Ogg Vorbis audio, including the ones that don't mention it in the marketing materials, as do a lot of other handheld music players that aren't iGadgets or Zunes. I can't decide if audio-only-webm is likely to displace Ogg Vorbis at some point or not. The good news is that you can take Ogg Vorbis audio and move it to a webm format without losing any quality.)

      tl;dr: Vorbis audio and support for it seems to be a lot more widespread than people usually realize.

      --
      Hacker Public Radio is our Friend
  2. Great, but how about patents? by bircho · · Score: 3, Interesting

    Apple has a lot of patents on audio/video compression. Have they licensed those for free for this implementation? How about another implementation or fork? Will those have the same license?

    1. Re:Great, but how about patents? by BasilBrush · · Score: 4, Informative

      Apache License...
      3. Grant of Patent License. Subject to the terms and conditions of this License, each Contributor hereby grants to You a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable (except as stated in this section) patent license to make, have made, use, offer to sell, sell, import, and otherwise transfer the Work, where such license applies only to those patent claims licensable by such Contributor that are necessarily infringed by their Contribution(s) alone or by combination of their Contribution(s) with the Work to which such Contribution(s) was submitted. If You institute patent litigation against any entity (including a cross-claim or counterclaim in a lawsuit) alleging that the Work or a Contribution incorporated within the Work constitutes direct or contributory patent infringement, then any patent licenses granted to You under this License for that Work shall terminate as of the date such litigation is filed.

  3. Useful for Airplay by Drakino · · Score: 4, Insightful

    Keep in mind any Airplay compatible device can use ALAC, but can't use FLAC. This includes the Airport Express units that have been out since ~2004 or so, and the newer non Apple devices with Airplay compatibility. This is likely a move to assist with 3rd parties wanting to integrate more with Airplay, as the relevant network pieces (Bonjour) are already out there in source form.

    Sadly I'm sure most people here will go on and on about how it's not FLAC, and whatever. For once, just at least appreciate that Apple is continuing to throw some interesting things out to the OSS crowd instead of deciding to nitpick it to death. If you don't want to use it, thats fine. Just really tired of the nitpickery and general negative outlook geeks around here tend to have. Cheer up for once :-)

    1. Re:Useful for Airplay by Anonymous Coward · · Score: 5, Insightful

      Geeks don't tend to just get negative for no reason whatsoever.

      LOL thanks I needed that laugh. Please do go on believing your opinions are objectively better, though. It's lovely to see that level of arrogance justified.

    2. Re:Useful for Airplay by schnikies79 · · Score: 5, Insightful

      Geeks are biggest fanboys on the planet. They get mad and everything, reason or not.

      --
      Gone!
  4. Re:open source, patent encumbered by JBMcB · · Score: 3, Informative

    Apache license clause 3, coward.

    --
    My Other Computer Is A Data General Nova III.
  5. What are ALAC's technical merits? by GWBasic · · Score: 3, Interesting

    Lossless audio compression is pretty brain-dead simple. If you think of how sticking a wav file in a .zip or .gz only saves about 10% of space, (give or take,) the most basic lossless codecs work by essentially zipping the mathematical difference between each sample. Because storing the difference between each sample, instead of the sample itself, is more likely to have repetition in audio; algorithms like .zip and .gz can then be applied.

    What I'd like to know is, considering how brain-dead-simple lossless audio compression is, are there technical merits for using ALAC, especially on embedded devices? Does FLAC rely on floating point when ALAC is purely integer, thus making ALAC easier to implement? Is it easier to seek within an ALAC? Or, is Apple's insistance on ALAC purely a "not invented here" mentality?

    --
    No, I will not work for your startup
    1. Re:What are ALAC's technical merits? by PowerMacG4 · · Score: 3, Informative

      I've heard that ALAC was easier to decode on embedded devices back when they crafted it. FLAC was too processor-intensive, especially because you could choose different levels of compression that would have inconsistent decoding requirements.

    2. Re:What are ALAC's technical merits? by boristhespider · · Score: 3, Interesting

      I actually don't know the details about ALAC but I know it's not what you're speculating -- FLAC Is built on integer calculations and is a very lightweight lossless codec (especially compared to something like Monkey's Audio or TAC which are very intensive and not so pleasant to use as active media files rather than archiving, although their compression is better) and is good for playback with limited CPU. I'd guess that ALAC is also integer, and that practical differences from FLAC are minor.

      I think it comes down partly to a not-invented-here thing, and also that FLAC typically sits in its own container or in an OGG container, while ALAC sits in an MP4 container - not that Apple couldn't have embedded FLAC into MP4 if they really wanted to.

  6. Re:This patent grant protects Apple,. not you by Farmer+Tim · · Score: 3, Insightful

    Two questions:

    1- Who but a knuckle dragging moron would accept a software license and then try to sue the software's creator?

    2- Why is this clause evil when it's software from Apple, but not a problem when it's from the Apache Foundation?

    --
    Blank until /. makes another boneheaded UI decision.