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danox574
Apr 9, 2013, 05:26 PM
Ignoring the fact that this makes no sense, I have a need to move my 256k AAC files to another format natively supported by a device without reducing quality further. I don't mind the disk bloat.

XLD and xACT won't use compressed m4a files as a source, MAX will but its removing album artist tags and blowing up my album art to a png instead of the previous jpg. Is there a OSX or PC software that can do this in one pass without tag changes?



blueroom
Apr 9, 2013, 05:29 PM
FLAC is lossless, AAC is not. Pointless to convert from a lossy format to a lossless. Just make it a 256k MP3.

danox574
Apr 9, 2013, 06:14 PM
You seem to be assuming no fidelity will be lost going from 256k AAC to 256k MP3, but that is wrong. It's not conversion, it's re-compressed into MP3 from a lossy source to begin with and degrades the audio further. Going to FLAC solves a hardware compatibility problem I have with no further reduction in sound quality beyond what already existed in the 256k AAC compression.

Edit: dbPowerAmp does a excellent job on this without any tag problems, I've found.

cheekypaul
Apr 10, 2013, 01:33 AM
You seem to be assuming no fidelity will be lost going from 256k AAC to 256k MP3, but that is wrong. It's not conversion, it's re-compressed into MP3 from a lossy source to begin with and degrades the audio further. Going to FLAC solves a hardware compatibility problem I have with no further reduction in sound quality beyond what already existed in the 256k AAC compression.

Edit: dbPowerAmp does a excellent job on this without any tag problems, I've found.

hi danox, i see your concern.
did dbpoweramp solve it, or are you saying it has in the past? afaik, dbpoweramp is pc only, although i know it will run on a mac via parallels or wine.

Julien
Apr 10, 2013, 06:43 AM
You seem to be assuming no fidelity will be lost going from 256k AAC to 256k MP3, but that is wrong. It's not conversion...

It IS a conversion (aka: transcoding) and quality will be lost. Lossy to lossy is always a BAD idea (http://wiki.hydrogenaudio.org/index.php?title=Transcoding). The only way to do this and maintain SQ is to re-rip the CD (or lossless source).

Johbremat
Apr 16, 2013, 05:58 AM
Sorry Julien but danox574 looks to understand it all perfectly.

You're correct in saying it's conversion, but not transcoding. Conversion is a process by which a unit is changed, altered; transcoding is simply providing it a different container.

Reading in context the statement you quoted, danox574 understands that AAC to MP3 is a lossy conversion. Also understands that transcoding from AAC to FLAC will result in transcoding the existing library that will result in bloat, but provides the compatibility required.

If it's not clear, there'll be no generational loss. The AAC file is exploded to WAV (maintaining its existing quality) and compressing the WAV to FLAC there won't be any degradation from lossless to lossless.

stchman
Apr 16, 2013, 02:07 PM
If you don't mind us asking what is the device?

I have never heard of a device that supports FLAC but not AAC.

Destroysall
Apr 16, 2013, 02:27 PM
If you don't mind us asking what is the device?

I have never heard of a device that supports FLAC but not AAC.This. I thought that AAC was now an open source? If anything, you could just convert to FLAC and not worry about it then, but your files will be bigger.

Johbremat
Apr 16, 2013, 06:42 PM
AK100 by iriver and Astell&Kern comes to mind. From memory it only plays a selection of open-source, license-free lossless formats.

HiFiMAN HM series of audio players I think has wider codec support, but believe still excludes AAC/ALAC.

Giuly
Apr 17, 2013, 07:26 AM
iOS devices won't play FLAC, but ALAC, so you're creating another hardware incompatibility right there.

Johbremat
Apr 17, 2013, 08:07 AM
iOS devices won't play FLAC, but ALAC, so you're creating another hardware incompatibility right there.

Except that:


We're not talking about iOS devices
You'd be incorrect (****************2ZL5O)

Giuly
Apr 17, 2013, 10:54 AM
1. OK.
2. I meant iTunes, not some iTunes clone from the App Store.

ChrisA
Apr 17, 2013, 06:22 PM
Ignoring the fact that this makes no sense, I have a need to move my 256k AAC files to another format natively supported by a device without reducing quality further.

iTunes will do the conversion. If you need to convert AAC to MP3. Set iTune's default formt to MP3 select the tracks and double click. Then selet "convert to MP3.

You WILL lose quality unless you select and MP3bit rate that is higher than the AAC bit rate. and even then you loose something. Will you notice? I don't know.

But iTunes will do this for you and it will keep all the tags. You end up with BOTH formats in the iTunes library. Pull out the ones you need.

Johbremat
Apr 17, 2013, 08:55 PM
Reading the subject line, first and third posts, looks that the OP was looking to convert from AAC to FLAC and was able to achieve this using dbPowerAmp.