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Revision as of 05:06, 15 March 2012 editJimthing (talk | contribs)Extended confirmed users9,941 edits Futility of the format?← Previous edit Revision as of 11:58, 7 January 2013 edit undoRegression Tester (talk | contribs)Extended confirmed users, Rollbackers1,528 edits low power?Next edit →
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== low power? == == low power? ==

<blockquote> <blockquote>
Furthermore, the speed at which it can be decoded makes it useful for a limited-power device such as the iPod. Furthermore, the speed at which it can be decoded makes it useful for a limited-power device such as the iPod.
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I don't think that FLAC or SHN having better decoding performance necessarily makes ALAC's decoding performance poor.--] (]) 16:24, 3 May 2009 (UTC) I don't think that FLAC or SHN having better decoding performance necessarily makes ALAC's decoding performance poor.--] (]) 16:24, 3 May 2009 (UTC)

:If there's data that shows that an iDevice runs longer or uses less energy playing FLAC than common lossy formats, then this should stay. I bet the contributor assumed it would, but would the increased data reads outweigh the reduced processing? It's not an encyclopedia-worthy assumption. I'm removing it.--] (]) 18:27, 4 August 2012 (UTC)

::Sorry, but the comment is not stating it's better/worse than FLAC or other lossless, so should stay accordingly, unless proven otherwise as being entirely incorrect. The rest of your comment is baseless assumptions on others actions, whilst making assumptions on facts you don't know the answer to, hence should have been left alone accordingly. 10:33, 7 January 2013 (UTC)

:Is there any source for the claim that ALAC decoding is faster or consumes less energy than decoding any other codec? Is it less energy-consuming to play ALAC files than playing uncompressed PCM audio? I did not test (and the claim is not completely implausible) but it sounds a lot like marketing speech to me that needs a source.--] (]) 11:58, 7 January 2013 (UTC)

== worst case ==
The compression attempt can backfire. I just compressed a 19 kbps WAV file (~500KB) with ALAC (with iTunes 10.6), and the result is a 217 kbps file. So I see there are no sanity checks in the implementation.--] (]) 18:27, 4 August 2012 (UTC)
: "Sanity checks in the implementation" what's that supposed to mean? Little to no proper explanations in your comments. Explain much further please, if you're gonna bother to edit info on here. ] (]) 10:27, 7 January 2013 (UTC)
:] is a container, ALAC a codec. Typical WAV files contain ] audio with a bitrate araound a magnitude higher than 217 kbps. Your wav file already contains compressed (lossy) audio, there is no lossless codec that can compress already compressed audio further, the same is true for video codecs. (This of course depends on the definition of "already compressed" but it is at least true for common - including older - codecs like mp3, wma, mpeg2video.)--] (]) 11:51, 7 January 2013 (UTC)


== Removed Questions == == Removed Questions ==

Revision as of 11:58, 7 January 2013

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Mentions

I could go on and on, but I can't find a single example of "Apple Lossless Encoding" mentioned on the Apple website. Funnily enough, a Google search for site:www.apple.com "lossless encoding" returns two pages that don't actually contain the phrase "lossless encoding". AlistairMcMillan 01:30, 9 Nov 2004 (UTC)

paradox?

isn't a lossless encoder a paradox? i dont understand, nor does the article explain, how a compressed audio format could possibly be equillivant in quality to uncompressed data. any further explination would be appreciated. Cacophony 08:07, Nov 25, 2004 (UTC)

Lossless compression formats are actually quite common. See Lossless data compression. AlistairMcMillan 15:15, 2 Dec 2004 (UTC)
Thanks for the link, that is what I was looking for. I'll add it to the "see also" section. Cacophony 17:47, Dec 2, 2004 (UTC)
That page is already linked from the article under the word "lossless". AlistairMcMillan 18:35, 2 Dec 2004 (UTC)
I'm rather surprised that someone on the internet has never comes across loseless compression before. Zip? Gzip? Bzip2? Rar? Ace? 7zip? PNG? Gif? Have you really never encounter any of these before Nil Einne 16:45, 27 October 2006 (UTC)
Until lossy compression became a term with a lot of exposure, most people never though about the fact that *zip programs were lossless, that's all. — Saxifrage 17:53, 27 October 2006 (UTC)
Really: I would have thought most people knew zip is a form of compression. That's what they often use it for (okay some are primarily interested in the archiving functions)... And if it is a form of compression it doesn't take much thinking to realise it's lossless Nil Einne (talk) 11:57, 25 September 2009 (UTC)

Lossless ITMS sales?

Can someone comment on whether or not it is possible to buy music through the iTMS in Apple Lossless format? 65.200.4.130

The music available from the iTMS is encoded in ~128 kbps AAC audio only. AFAIK lossless audio is not available. HTH, bdesham  20:04, 5 November 2005 (UTC)
No, sorry. As of a few years ago iTMS has improved a little, but still currently only offers lossy *non-DRM* (previously it was DRM'd) at 256 kbps AAC audio files. This is much to the annoyance of a great many users who would like the choice hence do not buy anything there (choice is just not Apple's way of doing things though, hence another reason why rampant torrenting exists!). It's generally thought to have been chosen to be done like this because ALAC –and other lossless audio– file sizes tend to be 5x bigger, so both data transfer and data storage are issues. Storage is still a BIG issue on portable devices, with relatively very limited space on them even today (even the 160 GB on a Classic iPod is not much space if lossless is being used). Data transfer is an issue across the board. For local transfers, whether wired (though Thunderbolt deals with that now!) or wireless (wifi is still much too slow). And for wide-area internet transfers, most of the western world doesn't have fast enough connections (both downloading, but especially uploading too – large-scale data backup thus impossible currently!).
I exclusively encode manually into ALAC now though, because the amount of cheap non-portable computer-based storage available is massive now (12 TB of external Thunderbolt RAID-10 does nicely for audio ). So clearly, thinking longterm, if today storage is not an issue in the non-portable world, in a few years even in the portable world this stuff is not going to even be an issue. And data transfers will improve for both eventually. Hence, no reason to lose quality now if you're archiving content. Jimthing (talk) 06:48, 27 August 2011 (UTC)

Needs sources etc

Quite a number of parts are in need of courses, for example:

Testers using a selection of music have found that compressed files are about 40% to 60% the size of the originals depending on the kind of music, similar to other lossless formats. Compared to most other formats, Apple Lossless is not as difficult to decode, making it practical for a limited-power device such as an iPod.

Nil Einne 16:43, 27 October 2006 (UTC)

Yeah. I tagged the last sentence as needing a citation. The first could probably use one too, but since it's just corroborating a non-converserial statement by Apple, it's less of a big deal. — Saxifrage 17:54, 27 October 2006 (UTC)
Well according to the comparison referenced in the article, the decoding speed of Apple Lossless is somewhere between that of FLAC and WavPack. So while it's not as difficult to decode as some other formats, I think saying "most other formats" is too ambiguous without actually saying which formats you're comparing to. It is accurate to say that Apple Lossless is suitable for playback on the iPod, however the Rockbox software can also play FLAC, WavPack, and Shorten on iPods. There isn't anything particularly special about the technology in Apple Lossless, and the fact that it can be played on iPods is mentioned in the preceeding paragraph. So I don't see any reason to keep this sentence and I'm going to remove it. --Mcoder 02:29, 5 November 2006 (UTC)


Lossless audio coding is a huge topic for discussion. Lossless audio coding is based on 'Entropy' of the signal which actually is amount of redundant information present in audio data to be compressed. Its all involved with statistical algorithms like prediction and database creation/seach algorithm. —The preceding unsigned comment was added by 202.56.254.194 (talk) 08:42, 17 January 2007 (UTC)

Apple Lossless is based on linear predictive coding. Encoding the difference between the prediction and the actual signal is referred to as 'entropy coding'. This subject would be more appropriately addressed in the linear predictive coding article, rather than here. --Mcoder 03:50, 22 January 2007 (UTC)

Add Link Back

I would like to see if anyone would object to me adding the link back to our site, The Lossless Audio Blog? Our site tries to bridge the gap between the forums and the various EAC Guides by providing information on getting started with lossless audio formats as well as current news and information. Because the Wiki pages for lossless audio formats are such a great place for those learning about the various formats I feel that our site compliments this and have heard from a lot of users voicing the same opinion.

Thanks for the consideration! Windmiller 12:27, 25 January 2007 (UTC)

Link Added Windmiller 14:07, 11 February 2007 (UTC)

I visited this page and it appears to be one of those commercial sites that try to harvest clicks. There seemed to be zero information there at all, let alone a blog. Telosmachina (talk) 06:50, 3 March 2010 (UTC)

low power?

Furthermore, the speed at which it can be decoded makes it useful for a limited-power device such as the iPod.

hm, according to the page listed as reference, both flac and shn have a better decoding performance ... not sure, whether this phrase adds any valuable information to the article ... would propose to remove it. 85.127.84.54 (talk) 18:42, 17 January 2009 (UTC)

I don't think that FLAC or SHN having better decoding performance necessarily makes ALAC's decoding performance poor.--69.254.67.10 (talk) 16:24, 3 May 2009 (UTC)

If there's data that shows that an iDevice runs longer or uses less energy playing FLAC than common lossy formats, then this should stay. I bet the contributor assumed it would, but would the increased data reads outweigh the reduced processing? It's not an encyclopedia-worthy assumption. I'm removing it.--67.170.192.66 (talk) 18:27, 4 August 2012 (UTC)
Sorry, but the comment is not stating it's better/worse than FLAC or other lossless, so should stay accordingly, unless proven otherwise as being entirely incorrect. The rest of your comment is baseless assumptions on others actions, whilst making assumptions on facts you don't know the answer to, hence should have been left alone accordingly. 10:33, 7 January 2013 (UTC)
Is there any source for the claim that ALAC decoding is faster or consumes less energy than decoding any other codec? Is it less energy-consuming to play ALAC files than playing uncompressed PCM audio? I did not test (and the claim is not completely implausible) but it sounds a lot like marketing speech to me that needs a source.--Regression Tester (talk) 11:58, 7 January 2013 (UTC)

worst case

The compression attempt can backfire. I just compressed a 19 kbps WAV file (~500KB) with ALAC (with iTunes 10.6), and the result is a 217 kbps file. So I see there are no sanity checks in the implementation.--67.170.192.66 (talk) 18:27, 4 August 2012 (UTC)

"Sanity checks in the implementation" what's that supposed to mean? Little to no proper explanations in your comments. Explain much further please, if you're gonna bother to edit info on here. Jimthing (talk) 10:27, 7 January 2013 (UTC)
WAV is a container, ALAC a codec. Typical WAV files contain PCM audio with a bitrate araound a magnitude higher than 217 kbps. Your wav file already contains compressed (lossy) audio, there is no lossless codec that can compress already compressed audio further, the same is true for video codecs. (This of course depends on the definition of "already compressed" but it is at least true for common - including older - codecs like mp3, wma, mpeg2video.)--Regression Tester (talk) 11:51, 7 January 2013 (UTC)

Removed Questions

I removed two questions that asked for assistance with using Apple Lossless. As it states, this is not a help forum nor a place to ask for technical assistance.

Deepcloud (talk) 09:05, 12 March 2009 (UTC)

09:05, 12 March 2009 (UTC)

Futility of the format?

Is there actually any reason why Apple "created" this format, since codecs like Flac and Shorten already exist? It seems to me that the *only* reason Apple created this format was so it could have an Apple name. Basically, Apple just added a lossless format that's actually technically inferior to ie. Flac, just because it could.

Imagine every company that makes MP4 players made their own format.. there's no real rational reason why this format is any good; therefore, I am forced to conclude that Apple only looks at their own interests, and doesn't care about the people.

Prove me wrong, please. Please. —Preceding unsigned comment added by SeriousWorm (talkcontribs) 00:11, 4 June 2009 (UTC)

I think that apple simply wanted to provide a lossless option optimized for its hardware in the absence of any established de facto standard. Killakittens (talk) 21:30, 6 September 2009 (UTC)
It was my understanding that FLAC was unsuitable for streaming (such as Airtunes) or reading big chunks sequentially from storage (remember early iPods had little hard drives, so any time the drive was powered, the battery life would shorten). What about chapter marks for audiobooks? Also, can FLAC be tagged with metadata, artwork, lyrics, ratings, etc? Apple Lossless is exactly like an MP3/AAC track in that regard. --68.103.141.28 (talk) 01:09, 25 September 2009 (UTC)
I doubt metadata had much to do with it. FLAC does support metadata and in any case I'm pretty sure the metadata of Apple Lossless is a function of the MP4 container not the codec. I don't know much about FLAC, but from the little I know see no reason why it would be intrinsically unsuitable for streaming or big chunks sequentially and I believe people do stream FLAC. I suspect other factors had more to do with it, probably not so much Apple's desire to have their name but more to have a format they control. Microsoft also has WMA lossless after all. While I can find some sources , I don't know whether there's much merit to mention any of this in the article in which case this discussion is OT Nil Einne (talk) 12:24, 25 September 2009 (UTC)
All of the above and more. My reading on the background to ALAC is they didn't want any potential patent issues, as the development and ownership of the FLAC codec was unclear at the time. However FLAC has since emerged clear of any of these issues; but of course that's with the benefit of hindsight, and Apple clearly wouldn't have known that when they needed a lossless codec for their products, so had to pursue their own highly similar codec instead. As for being "futile", far from it. Apple now have the upper hand in the lossless game after open sourcing the ALAC codec, as it can be used on not only their own iDevice/iTunes products, but also all other manufacturers can add the reference version of the codec (instead of the unlicensed reverse engineered libavcodec) to their supported formats without legal or possible technical issues, whereas Apple will never add FLAC natively into their iDevice/iTunes product ecosystem. Thus both better ALAC compatibility with external docking device manufacturers, and ALAC audio file format sales through the iTMStore seem ever more likely in the future. --Jimthing (talk) 07:03, 1 December 2011 (UTC)
It was definitely about the fear of patent trolls coming after them; and this applies both to Apple and to Microsoft. (It's not about the actual ownership of FLAC, but rather that it may have used certain techniques that are patented. No one will go after a bunch of free software people; there's no money in it. But if Apple or Microsoft started using them, then there would be a target.) They both created their own lossless formats for this reason. Tossing out the old "control" canard doesn't really apply to a format that isn't widely used, but the point aout FLAC streaming could be true. (Though I have heard that, internally, the iTunes Store uses FLAC to store masters.) But I don't think any of this is germane to the article. Kirkmc (talk) 09:47, 1 December 2011 (UTC)
I don't think that's factually correct. I don't believe Apple stores on its server computers so-called "masters", as such objects are the responsibility and ownership of the content owners themselves (record companies, content owners, etc.), or even higher-quality encodes of any content formats (in ALAC/FLAC or anything else). Content owners have to encode and format content into Apple's approved format standards, then upload to Apple using tools Apple provide to do so. Apple have two main methods for content providers to upload content in Apple's approved standards through their iTunes Connect service. If you're big enough and can sell minimum sales amounts (earning thresholds in each territory), then according to this link (http://www.apple.com/itunes/content-providers/music-faq.html ) Apple provide music indie content owners with a piece of software called "iTunes Producer" in which to format their content into music files sellable through the store and in order to upload to iTunes (they can alternatively get an encoding house to do the required encoding), or alternatively they can use an approved aggregator (aggregators: https://itunesconnect.apple.com/WebObjects/iTunesConnect.woa/wa/displayAggregators?ccTypeId=3 ) to do all this on their behalf; especially required if they do not meeting minimum sales thresholds anyway. Certain music-related file types (music videos, ringtones, concert films, and iTunes LP) they sell will require an Apple-approved encoding house to be engaged to so such formatting. It is a similar process for other media types (books, films, apps, etc.). --Jimthing (talk) 23:12, 6 December 2011 (UTC)

...FYI, it looks like Apple are asking for masters now, currently limited for use as their Mastered For iTunes (MFI) specifically mastered 256 kbps AAC sales, but hopefully lossless sales will arrive as Apple can presumably re-encode these MFI-provided masters they will already have into lossless files (or whatever format is needed for adaptive streaming usage. See: http://www.guardian.co.uk/technology/2012/feb/28/apple-audio-file-adaptive-streaming ). Sounds positive, but we'll see! Ref: "Provide High Resolution Masters" section here http://images.apple.com/itunes/mastered-for-itunes/docs/mastered_for_itunes.pdf --Jimthing (talk) 07:41, 11 March 2012 (UTC)

Future proofing the format

I'm attracted to Apple Lossless because it's smaller than raw AIFF/WAV, can be tagged with metadata, and it's very easy to use with iTunes/Pod/Phone. But I'm concerned for the future. I know I can re-rip Lossless into other formats, but "what if" some day there's no more iTunes or Apple? --68.103.141.28 (talk) 01:04, 25 September 2009 (UTC)

This isn't really the place for such questions. I suggest you try the WP:RDC for factual questions. However no one can predict the future so this isn't a factual question. However it isn't necessary to rerip, simple conversion programs exist which can convert Apple Lossless into other formats such as uncompressed PCM wave or AIFF or some other lossless compresion like FLAC. As mentioned in the article, this includes open source utilities. So it's likely you will be able to decode and convert Apple Lossless in the future, even if no program supports it, if you are able to modify the existing code or willing to pay someone else to do it, to work on whatever modern platforms existthen. Alternatively you can use either an uncompressed format like PCM wave or other lossless compression format, perhaps one like FLAC which is widely supported by the open source community and so may be more likely to survive into the future. A final possibility would be to use Apple Lossless for now, but reevaluate every 3 or 5 years in the future or something of that sort whether it's still prudent to use it and if not, mass convert all your files to whatever format you feel is best then. BTW as far as I'm aware both FLAC is capable of support metadata as mentioned in the article, as is RIFF wave of course. --Nil Einne (talk) 12:15, 25 September 2009 (UTC)
(under "Futility of the format?" topic above, see my "All of the above and more..." comment.) Basically the future's a lot brighter now the original reference version has been open sourced by Apple ;-) --Jimthing (talk) 07:10, 1 December 2011 (UTC)
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