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pb1300
Mar 25, 2010, 01:05 PM
Per Wiki:

Apple claims that audio files compressed with its lossless codec will use up "about half the storage space" that the uncompressed data would require. 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.


From reading that, I assume that going Apple loseless would give me smaller files, no? Well how come when I converted an AAC file to Loseless, its almost 4 times in size?


Edit: can we move to iTunes forum please.



miles01110
Mar 25, 2010, 01:07 PM
Well how come when I converted an AAC file to Loseless, its almost 4 times in size?

The real question is why you're converting AAC to Lossless in the first place. Converting a lossy file to lossless is a waste of space, as you're not getting lossless quality. You can't add information to a file to make it lossless if it's already been compressed.

pb1300
Mar 25, 2010, 01:09 PM
The real question is why you're converting AAC to Lossless in the first place. Converting a lossy file to lossless is a waste of space, as you're not getting lossless quality. You can't add information to a file to make it lossless if it's already been compressed.

I didnt know what Loseless was. So should I just convert any MP3 I have in the future to loseless, or is AAC fine?

Again, sorry for posting this in the wrong forum.

miles01110
Mar 25, 2010, 01:10 PM
I didnt know what Loseless was. So should I just convert any MP3 I have in the future to loseless, or is AAC fine?


If you want Lossless quality audio you have to rip it as Lossless directly from the CD. If you're worried about space, AAC is fine- but you can't convert an existing MP3 to Lossless quality.

J the Ninja
Mar 25, 2010, 01:12 PM
Don't convert AAC or MP3 to anything else, ever. If you want more quality, you will have to re-rip. If you have the drive space for it, rip everything to Apple Lossless or FLAC, and then you always have a digital master copy you can use to encode whatever other versions you may need.

brentsg
Mar 25, 2010, 01:14 PM
I didnt know what Loseless was. So should I just convert any MP3 I have in the future to loseless, or is AAC fine?

Again, sorry for posting this in the wrong forum.

There is no reason to convert mp3s to aac either. What are you trying to accomplish?

Converting one lossy format to another just results in reduced quality.

Converting a CD to apple lossless format is a way to reduce file size with no decrease in audio quality from the original format.

mchalebk
Mar 25, 2010, 01:15 PM
Lossless results in smaller files compared to uncompressed audio files like AIF and WAV. So, if you're ripping a CD and don't want to lose any sound quality at all, using a lossless codec will maintain 100% of the quality, but with smaller files. These files will be about half the size of uncompressed files.

AAC and MP3 are lossy codecs. They result in much smaller files (10-20% of uncompressed) with some loss of information. There may or may not be some degradation of the sound quality compared to uncompressed or lossless. For most people, AAC and MP3, when converted at a decent bit rate, are plenty good enough.

If files are already in AAC or MP3 format, there is absolutely no benefit in converting them to lossless.

mstrze
Mar 25, 2010, 02:24 PM
And just to be clear...

If you directly copied over the AIF files from your CD (and I mean open the CD 'folder' and pulled the file and stored it on your desktop) exactly as found on the Compact Disc, they would indeed be about twice the size of a lossless iTunes-created version of the file, as your original post says. Converting them to lossless would result in a file 40-60% of the size, AAC (with some loss in quality) might be 20-25% of the original size, various bitrates of MP3 could get you much smaller, but noticeably messier-sounding files.

The reason your translation came in as a larger size is that your AAC file is already a much smaller transcoded version of the original music. Turning it into a lossless file would make it larger, because it natively creates a larger file, but not nearly as large as an original AIF (CD) file.

So, as others have said do NOT transcode AAC or MP3 files to lossless. You certainly won't lose any quality...it's a lossless format after all... but you WILL indeed create larger files than you already have with no increase in quality. (I know it sounds counter-intuitive, but that's the case.)

From now on, DO encode your CDs using Apple Lossless if you want the higher quality. If the sound quality has never bothered you before, stick with AAC and save hard drive space. :)

pb1300
Mar 25, 2010, 02:50 PM
And just to be clear...

If you directly copied over the AIF files from your CD (and I mean open the CD 'folder' and pulled the file and stored it on your desktop) exactly as found on the Compact Disc, they would indeed be about twice the size of a lossless iTunes-created version of the file, as your original post says. Converting them to lossless would result in a file 40-60% of the size, AAC (with some loss in quality) might be 20-25% of the original size, various bitrates of MP3 could get you much smaller, but noticeably messier-sounding files.

The reason your translation came in as a larger size is that your AAC file is already a much smaller transcoded version of the original music. Turning it into a lossless file would make it larger, because it natively creates a larger file, but not nearly as large as an original AIF (CD) file.

So, as others have said do NOT transcode AAC or MP3 files to lossless. You certainly won't lose any quality...it's a lossless format after all... but you WILL indeed create larger files than you already have with no increase in quality. (I know it sounds counter-intuitive, but that's the case.)

From now on, DO encode your CDs using Apple Lossless if you want the higher quality. If the sound quality has never bothered you before, stick with AAC and save hard drive space. :)

I will just continue to use AAC since all of my 4000+ songs are AAC format. The reason I asked in the beginning was because I just recently read something about Loseless, so I was curious to what it did. I appreciate the knowledge everyone dropped here.

dernhelm
Mar 25, 2010, 03:01 PM
Some people like lossless quality recordings. Search for FLAC on the internet, and you will find lots of people who have captured (sometimes live) recordings in this lossless format. They are often free, legal, and a lot of fun to listen to. Bela Fleck and the Grateful Dead have released a lot of material in this manner.

But iTunes/iPods/iPads cannot play back lossless FLAC encoded audio natively, instead Apple's lossless codec of choice is (unsurprisingly) Apple Lossless. So if you have FLAC encoded audio, and you want to transfer it into Apple's eco-system, the easiest thing to do is to burn it to CD (using Toast or some such app), and then rip the CD into Apple Lossless. If you do that, what you'll see is that the size of the FLAC file and the size of the Apple Lossless file are roughly the same.

But both are about 1/2 the number of bits on the raw audio CD. That's where Apple gets their 50% number.

rabbisound
Mar 25, 2010, 03:11 PM
Apple lossless must be pretty good, as artists selling their music on iTunes upload their music to the apple servers using iTunes producer which encodes their cd as apple lossless, I guess apple are future proofing the store for when they eventually offer lossless, only been like this for around two years now prior to that labels vendors artists encoded in iTunes producer as AIFF, just shows ALAC is believed in.

Cromulent
Mar 25, 2010, 03:16 PM
So if you have FLAC encoded audio, and you want to transfer it into Apple's eco-system, the easiest thing to do is to burn it to CD (using Toast or some such app), and then rip the CD into Apple Lossless.

Why in Gods name would you do that? Just use Max to convert the FLAC directly to Apple Lossless.

GermanSuplex
Mar 25, 2010, 04:45 PM
^Agreed.

What's more, if you're burning to CD and re-ripping, I hope you're using a secure ripper or else you may have errors on tracks. I had a few CD's (Both burned myself and store-bought) that had errors on them even though visibly, they were in like-new condition.

As others have mentioned, lossless is only good for ripping from the source lossless files. Now, I do have lossy-sourced Apple Lossless files, but these are from things like DVD audio rips. Many cheap concert DVD's don't have a lossless track, they only have a lossy AC-3 audio track. I will rip the audio, convert it to Apple Lossless and archive it. Then, if I ever want to convert to AAC, mp3 or whatever, I don't have to pull the DVD back out and re-rip, I can just convert from the lossless files since they are the same quality as the audio on DVD. So lossy lossless can be useful if you understand what you're getting.