iTunes .MP3 to .AAC Conversion
 

Is there a program that will encode all my .MP3 and .MP4 audio files to the 128kps .AAC format but ALSO delete the previous file?

In iTunes, it allows you convert quite easily, but it simply makes a duplicate copy of the file in .AAC format. Since the .AAC format requires a lot less space, and I have nearly 5,000 songs, it is somewhat of a priority. If anybody can help here, I would be grateful.

BTW, iTunes 7.0.2 and Windows XP Professional.

I did this with my library (actually I went from .wav to apple lossless) - but I just used iTunes. You can add the field "kind" to the table and sort the files that way, deleting the originals after the copies are made. Just make sure that you've doubled the number of items in your library before you delete! I don't think there would be a good way of doing this without using iTunes. After all, the program would need to alter the itunes xml and library files or else all of your music will be missing from your library! Given what a pain in the ass that would be, I preferred to manually delete things after conversion.

Of course, this method, while relatively safe, requires that you have a bit of extra storage and, depending on the size of your collection, a bit of time. I did my library (8,000 tracks of mostly classical music, so approx. 32 days worth of music originally stored in 400 gb) is a couple of days. It went surprisingly well.

If you have access to the original source (CD), you will be better off ripping directly to AAC instead of converting. Any converting process from compressed music file to compressed music file will result in a sound that is lower in quality than the original compressed file.

Bumping an old thread.

I have lots of MP3s, but when I try to have itunes convert them they're protected and can't.

Can ANYONE help explain to me what the heck is going on? I have a brand new I-Touch and it's nothing but a pretty paperweight right now because itunes won't let me load anything onto it.

1) How many MP3s are we talking about?

2) Where did you get them?

see I always wondered about the truth to that.

My understanding is that there is a bit of an algorithm that analyzes the "non human" frequencies and removes those while saving the remainder under whatever format "translation" output you desire (mp3 etc..)

I figured if all the garbage is removed already it would just basically go "well I couldn't really remove anything but uh, here you go"


the only time what you said could apply is if they were going from a lower quality bitrate to a higher quality bitrate.

like 128 converted to 320 would be completely and utterly pointless as the data that represents the difference was already removed.

oh well

A couple hundred, and not in a legal fashion.

That's true to a certain extent, but a) different algorithms remove different information and b) the second algorithm may perform worse with the reduced information from the first. When you recompress you're losing the removed information set from both algorithms. Some parts might overlap, like a lowpass filter, but there is inevitably some additional loss.

Whether that's a perceptible loss is a different story. I have lots of OGG->AAC recompressed files on my iPod, both versions high bitrates, I can't tell the difference. If your bitrates are high enough it's probably fine. If you're doing a 128k MP3->96k WMA it's gonna sound like crap.

I figured since we're on the same topic of iTune. I've recently moved my music from my computer to the laptop and installed iTune on the laptop. I converted the mp3's and wma's to a format that's for ipod touch. However, I noticed that there are massive number of duplicates.

Such as

Song 1.xxx
Song 1 1.xxx
Song 1 2.xxx
Song 2.xxx
Song 2 1.xxx

Any sure fire way using iTune to delete all the duplicates? I've googled the topic and it mentions going to Edit->Show Duplicates and then delete everything in the list. But will that delete just the duplicates or all of the musics that were duplicated? Because when I did click on Show Duplicates, it would go

Song 1
Song 2

to:

Song 1
Song 1
Song 1
Song 2
Song 2

and when I look into itune folder, it would show that there are actually 3 Song 1 and 2 Song 2. So, if I delete all of them, it would also delete all of the songs that were converted by itune right? Meaning that I would have to start the process over of converting it.

feelgood, do the Edit->Show Duplicates. Then sort that list by date added or by kind (CTRL-J to add or remove columns from the table).

However, if your song titles are actually different from each other (as you indicated in your post), I'm not sure that iTunes will still see them as duplicates. If it doesn't, I'd sort the whole mess by length of track and see if I could work it out by hand from there.

Seaver, I'm still thinking about your problem with the protected MP3s. That may be a tougher answer.

http://www.hydrogenaudio.org/forums/index.php

I don't think there are any programs bold enough to delete the source file for you when doing such a large batch conversion. Also, from what I understand, MP4 used the AAC codec.

Absolutely correct, I cannot stress this enough.

See the lossy encoders not only remove frequencies, but also restructure the waveform. Ever lossy encoder will average data in the waveform each time you compress it to a new codec.
Absolutely agree. Do some blind tests to see if you can tell the difference between them.


If you are in windows do a search for "* 1" and all files with a 1 at the end of it will appear, then do the same for "* 2" and "* 3". Once you stop getting hits you can stop.

I figured out my problem, it's not that they're protected they're just not MP3 encoding.

They were WMA, the windows media player version of the MP3, which is superior from what I hear in compression/quality.

Itunes does not want to recognize WMA, so it pops up as protected.

Seriously - don't transcode. If you don't believe why this is bad, open the files up in a spectrum analyser...

Nah, I deleted and now I'm downloading all new ones. Apparently on bearshare everyone uses WMA.

My old collection was all MP3, but my computer crashed and I didnt backup so it was all recent downloads.

MP3 may use more space than the other formats, but I prefer that they can pretty much be played on any player, from iTunes to Media Player to my PVR to my iPod to my phone to my little Creative Zen. Obviously it's up to you.

Ew, WMA.

And what do you mean by that? Most double-blind listening tests rate LAME mp3s amongst the best along with ogg vorbis.

Ummm, not sure why you're quoting me when you say the above as I didn't say ANYTHING about quality. All I said was that MP3s were more universally compatible, even though they may take up more space than the format that the OP wanted to convert to.

If you wanted to transcode, you should have just used FooBar2000.

Conversions....
 

Not an iPod fan but have been doing some work for techno-illiterate mates...I stay in Windows Media Player and use MGTEK to convert wma and mp3 content from media player..takes a while to do the sync, but I stay in WMP and there are do duplicate files, the originals stay as they were. I use WMP across wireless to a laptop then to the stereo when I want full access to my music collection for parties etc....