The Old Joel on Software Forum: Part 4 (of 5)

WMA Conversion for ITunes

I've been weighing options for a portable jukebox. The iPod seems to be "best of breed" in terms of usability and form factor, but I'm not eager to get locked into the AAC file format.

There was an article in today's newspaper that discussed a new version of iTunes:

http://www.sfgate.com/cgi-bin/article.cgi?file=/chronicle/archive/2004/04/29/BUGBE6CHGU1.DTL

It briefly mentioned that the program will now be able to import WMA files and convert them to AAC. This raises the intriguing possibility of buying songs in WMA format for my PC, and then converting them for use on an iPod. It's not as good as the mythical WMA-enabled iPod, but it's a start.

I know that converting from one lossy audio format (WMA) to another lossy audio format (AAC or MP3) will cause some degradation of the audio quality. However, would anyone care to speculate about whether this would introduce a significant loss in quality? I.e., would a non-audiophile notice a difference between a music file converted from WMA into AAC format, compared to a "native" AAC music file?

Robert Jacobson
Thursday, April 29, 2004

Would you notice a difference if you reencoded from WMA to AAC, perhaps not (it really depends on the song and the sampling rate of the original).

However, the WMA -> AAC converter does not convert protected WMA files, so you can't buy from BuyMusic and the put them on your iPod.

You shoulnd't be concerned about ACC as a format (it's aprt of the MPEG4 spec and anyone can write for it). You might have reasonable reservations about FairPlay, the DRM Apple is using for its AAC files purchased from the iTMS. However there are ways to unprotect these files (check ./). That said, FairPlay seems to be mostly reasonable and I've had no qualms about buying music from the iTMS.

Lou
Thursday, April 29, 2004

Even non-audiophiles vary CONSIDERABLY in our 'acceptable range of quality'. For myself, almost any darn thing will do - my ears are pretty poor, the headphones I use are mostly crummy, and a lot of the music I like has very little depth or complexity. So I can get away with very low bit rates on mp3 (64k sounds fine for most of my stuff). Your milage WILL vary, depending on ears and equipment.

Even if you have good ears and/or complex music and/or good headphones, what's the bit rate and source of the WMAs that you are converting? If they are high enough, then the loss won't be THAT big a deal anyway. If they are CD rips, you might think about re-ripping.

The other question is whether it will be able to convert DRM'd WMA files or just unprotected ones. Frankly, you can already convert an unprotected WMA file to MP3 (which I believe the iPod handles just fine). So unless it can handle DRM conversion, I'm unclear what this really gets you.

Like you, I don't want to get locked into anyone's formats. For the moment, I've taken the stance of ripping my CDs as MP3 files, and I haven't bought a juke-box type device yet. I'm going to wait a bit and see how things settle out.

Michael Kohne
Thursday, April 29, 2004

It's not the losey vs lossless-ness, but the DRM (Digital Rights Management). The files you buy from iTunes have security built in so you can't turn around and give that tune you bought for $0.99 away to all of your friends for free. Therefore, converting to WMA or MP3 would lose that and Apple will never let it happen.

I personally use a Neuros (http://www.neurosaudio.com/index.aspx) that I've been very happy with. $200 for a 20GB unit - it's not as small or sexy as an iPod but it holds more tunes and sounds just as good.

5v3n
Thursday, April 29, 2004

I think Michael hit the nail on the head with "your mileage will vary". I for one can easily tell the difference between a CD and a ripped version of it at 192k (regardless of codec). Then again, I'm pretty sensitive to sound differences, and my equipment makes them noticeable. For most people though, I doubt converting from one format to another will result in noticeable loss of audio quality.

Elephant
Thursday, April 29, 2004

Thanks guys. As Lou suggests, I'm not so much concerned about the AAC format itself as about the proprietary DRM. The problem is that if I buy a large library of music from the iTunes Store, I won't be able to play them on another portable device. If three years down the road I want to switch to a jukebox from Creative or Rio, for example, I'll be SOL. Also, WMA seems to be better supported on "alternative" types of music players, like DVD players and in-car jukeboxes.

(Yes, I could theoretically burn the AAC files to CD, and then rip the CDs to WMAs or MP3s, but that's pretty klunky and also introduces the lossy conversion problem.)

For what it's worth, I checked out the DRM hack. There was one called "PlayFair" that was available on Sourceforge for a while, but it got taken down pretty quickly after Apple threatened litigation. It's probably still available in some IRQ channel, but I'm wary about relying on something as technologically and legally sketchy as this.

Buying CDs and then ripping them appeals to the antiquarian in me, although they are damn expensive. Plus, I haven't actually listened to a regular CD in ages. <g>

Robert Jacobson
Thursday, April 29, 2004

Oh, and since iTunes apparently won't convert the DRM-protected WMAs that are available from other music stores, that pretty much moots my original question.

Robert Jacobson
Thursday, April 29, 2004

There is a certain irony in the fact that you want to escape AAC lockin....by going to WMA.

.
Thursday, April 29, 2004

Will burning AAC to CD then ripping back to mp3 or WMA really be anymore lossy than somehow converting from AAC to mp3/WAM directly? Am I right in thinking that both methods require recoding?

Matthew Lock
Thursday, April 29, 2004

No, I didn't mean to imply that it would be any more lossy. Just that the AAC -> CD -> (Mp3|WMA) option or vice versa would be lossy plus a PITA.

Behind the scenes, it's probably doing the same type of conversion -- decoding the compressed music file into a noncompressed audio stream or temprary file, and then reencoding that stream or file into the other compressed format.

Robert Jacobson
Friday, April 30, 2004

I wonder if someone will ever make a virtual cd-writer driver that appears to these music programs as a real cd-writer but infact just creates wav files for you on the hard disk?

Matthew Lock
Friday, April 30, 2004

Funny Matthew -- I was wondering the same thing. Care to write one? <g>

About six ago I had a program for my laptop called "Virtual CD" or something similar. It copied an image of a CD to the hard drive, and then could use this for emulated CD access. It was quite useful at the time because my laptop had a clunky external CD drive.

Robert Jacobson
Friday, April 30, 2004