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IOS Music Open Source Apple

Apple's Lossless Audio Codec (ALAC) Now Open Source 526

Posted by samzenpus
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?"
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Apple's Lossless Audio Codec (ALAC) Now Open Source

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  • Why not... (Score:5, Insightful)

    by Lanteran (1883836) on Thursday October 27, 2011 @09:21PM (#37864032) Homepage Journal

    ...just use FLAC?

    • Re: (Score:3, Funny)

      by Anonymous Coward

      Because FLAC is for cyber-communists.

    • Re:Why not... (Score:5, Informative)

      by Tr3vin (1220548) on Thursday October 27, 2011 @09:25PM (#37864068)
      If you use and iPod, FLAC isn't going to play.
      • Re:Why not... (Score:4, Insightful)

        by bemymonkey (1244086) on Friday October 28, 2011 @12:14AM (#37865114)

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

      • by Hatta (162192)

        Then open the iPod software, so people can add support for the formats they prefer.

    • by Rinisari (521266)

      I for one would like to see an objective comparison of the two. I mean, I'm not about to re-rip everything I have as FLAC using ALAC or convert from one format to the other unless there are significant advantages.

      • You could try here...
        http://wiki.hydrogenaudio.org/index.php?title=Lossless_comparison [hydrogenaudio.org]

        It doesn't include results from this open sourced version - if there's any different at all to the tested version - though.

        From that table, it seems FLAC compresses about as well (depends on the exact track) while being much faster.

        But as others have pointed out, most of the technicalities may be moot if your target device is an iPod, iPhone or iPad - in which case ALAC is practically your only option.

        The same applies to F

      • by JBMcB (73720)

        The output of either one is going to be exactly the same as far as sound quality goes. They are lossless, their output is identical to the output of the original material. FLAC compression is slightly better than ALAC, the only real factors that come into play is platform support.

    • Am I correct that FLAC is not supported by the iPod, but ALAC is? If we're free to convert between the two now, what advantage is there in using FLAC instead of ALAC?

      • FLAC is more widely supported on just about everything that isn't an iPod.
        • For iPod read also iPhone, iPad and iTunes (Mac and Windows) of course.

          Kind of like saying "Application X is more widely supported on just about anything that isn't Windows."
          You can make a longer list of software and hardware that supports FLAC.
          But but number of units on which people are actually listening to music, then it's probably going to be ALAC.

          • You are forgetting things other than PMPs and smartphones (although I believe non-Apple smartphones are the majority) Also, you've got to consider who will actually bother with lossless audio. That tends to be enthusiasts, who have generally gone with FLAC. It's sort of like while VHS beat out Betamax, Betacam was dominant among professional usage.
            • You are forgetting things other than PMPs and smartphones

              No I wasn't. For example I was including Windows PCs with iTunes loaded.

              Oh, and then there's everything that's got a recent version of VLC on. VLC plays ALAC. Which will cover a heck of a lot of the things you're probably counting only for FLAC.

              • You are still ignoring the demographics issue. Even if there are more units that CAN play ALAC, there are almost certainly more units that DO play FLAC, and the people that have large libraries of lossless files tend to use FLAC.
                • Even amongst audiophiles, how many people really get anything out of having lossless on portable music devices? I know there is a hardy subset who travels with professional grade headsets and headphone amps, but do any of them use iDevices? From the last time I peaked into the audiophile world, pretty much ALL portable devices were scorned...

      • f we're free to convert between the two now, what advantage is there in using FLAC instead of ALAC?

        There are no differences between the two in terms of music quality, but FLAC:

        * Supports replaygain [wikipedia.org]
        * Has better tagging support (subjective)
        * Is better known [googlefight.com]
        * Contains better (any!) error detection (able to batch-verify downloaded files)
        * Is preferred lossless codec for vast majority of digital music vendors.

        But honestly, all of this is irrelevant compared to how well flac / alac fit into the rest of your ecosy

        • by tepples (727027)
          • FLAC supports RG. ALAC supports Sound Check. What's the difference?
          • Better known? Did you try comparing to (ALAC or "Apple Lossless")? I'll grant however that FLAC going by one name all the time without synonyms gives it an SEO boost.
          • You're right that MPEG-4 expects error detection to be handled inside the codec, but in practice, I thought that's what sha1sum was for.
          • Vendors? It doesn't matter much what the vendors use if the vast majority of digital music devices are made by Apple. (Archos's Android PMPs d
      • by Lanteran (1883836)

        What I mean by the comment is: why does apple not use FLAC, which is a widely supported and mature technology?

    • Hardware support support for ALAC in iPod and iOS devices, which leads to better battery life than pure software decoding. The first FLAC hardware decoder was only demoed a couple of years ago IIRC and I don't know if it has actually made it to market yet.

  • now it's FALAC, which sounds a bit phallic.

  • by bircho (559727) on Thursday October 27, 2011 @09:32PM (#37864128)
    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?
    • by BasilBrush (643681) on Thursday October 27, 2011 @10:02PM (#37864350)

      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.

  • Useful for Airplay (Score:5, Insightful)

    by Drakino (10965) <d_slashdot@minii[ ].net ['nfo' in gap]> on Thursday October 27, 2011 @09:38PM (#37864164) Journal

    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 :-)

    • Re: (Score:2, Redundant)

      by syousef (465911)

      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 :-)

      The reason geeks have a "general negative outlook" towards Apple is that they have been bitten by artificial restrictions imposed on their devices by Apple, or have overpaid for what they later realised were technically inferior products. Geeks don't tend to just get negative for no reason whatsoever. Do not make the mistake of thinking Apple has done this for the common good. They have their reasons and their reasons ultimately have to do with their profits.

      • by Anonymous Coward on Thursday October 27, 2011 @10:06PM (#37864386)

        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.

      • by schnikies79 (788746) on Thursday October 27, 2011 @10:07PM (#37864400)

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

        • by syousef (465911)

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

          You may not like or agree with their reasons, but they have reasons. Dismissing them out of hand and making them sound like mental patients reflects on you, not them.

      • by Dhalka226 (559740)

        I don't buy it. The idea that the geeks of Slashdot don't know about Apple's restrictions in advance, or are somehow incapable of evaluating the technical merits of products based on their specifications and only realize some technical inferiority after their purchase just doesn't wash. The average consumer, maybe; geeks, no. Not any deserving of the description.

        There are plenty of reasons to dislike Apple. The artificial restrictions and closed nature of so many of their products are certainly one; t

        • by epine (68316)

          They're just pissed off that a company doesn't operate the way they want it to

          Infinitely unimpressed by the Mickey Mouse copyright act, pissed off at the pretense that this is patriotic capitalism as it ought to work.

          There are several Lessig videos on YouTube about his new rootstriker campaign. As much as I admire his content, he always sounds like a man wearing little round glasses--standard issue for taking down a whomping willow, but I'm not sure it will fly in Washington.

          Lessig loves pointing out that

      • is because you [I'm guessing] are 23 years old and you aren't happy with your life. You want to belong to a club and you want a villain; the club you've chosen is "righteously indignant nerd" and predictably you've chosen Apple as your bad guy.

    • by imroy (755)

      I'm sure most people here will go on and on about how it's not FLAC, and whatever.

      Maybe. But the nice thing about lossless encoding is that there's no generational loss. So just transcode your FLAC rips to ALAC to send to your Airport thingies. Still equivalent to the original CD!

  • I cannot tell 256kbps VBR MP3 from lossless on my stereo. I listen mainly to classical music.

    • by sootman (158191)

      Once I realized a couple years ago how much (little) space my whole collection (about 200 CDs) would take up when ripped losslessly compared to how big my hard drives were, I re-ripped all my CDs as ALAC and I'll just transcode as needed. I had previously ripped them all as 192kbps MP3. It's not so much "I can hear the difference" as much as it is "there's no reason not to and I'm an anal-retentive neatnik and I like knowing that what I have is as good as it can possibly be." My whole collection is only abo

    • by JBMcB (73720)

      Snare rolls. I can never get LAME to encode them properly no matter what setting I use. It interprets them as noise and crushes them down into gibberish. There's a slowly building snare roll at the beginning of Royal Oil by the Mighty Mighty Bosstones that no lossy codec can seem to compress correctly.

      I can usually hear artifacts, even at high bitrates, in lossy codecs in the quiet passages of some songs. I listen with good quality headphones through an Audigy 2ZS PCMCIA sound card, which has a surprisingly

    • Try this (Score:3, Interesting)

      by garote (682822)

      If you're a non-audiphile trying to learn how to detect the difference with your ears, I suggest this:

      Rip a CD into ALAC. Then re-rip one of the tracks into 256k mp3. Open each track side-by-side in music player apps and set the volume the same. Play each version 10 seconds at a time, paying attention to the perceived location of each instrument in the room.

      You may find that it is easier to perceive that location while listening to the ALAC track.

      I won't bore you with the scientific details. GIYF.

  • Why, it's the sound of everyone still using MP3s, because no one gives a crap about formats that don't already play on literally everything...
  • by GWBasic (900357) <slashdot@a[ ]ewr ... m ['ndr' in gap]> on Friday October 28, 2011 @01:08AM (#37865372) Homepage

    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?

    • Re: (Score:3, Informative)

      by PowerMacG4 (575064)
      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.
    • by boristhespider (1678416) on Friday October 28, 2011 @02:59AM (#37865864)

      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.

      • The ipod came out like 10 years ago so it was over 10 years ago they would have made the decision on the format. The question is more what was the performance of FLAC on ARM devices and specially for ones that have to run on a battery. FLAC was certainly considered more CPU intensive than the likes of MP3 a decade ago.

        Considering Android didn't even include FLAC support until honeycomb (may 2011) I suspect there is a pretty good reason it was avoided prior to that.

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