No Tag Info w/ MP4/AAC Codec

**Spoon** · November 29, 2003, 01:03 PM

Re: No Tag Info w/ MP4/AAC Codec

Shows up in what program?

**jp63670** · November 29, 2003, 08:33 PM

Re: No Tag Info w/ MP4/AAC Codec

No tag information is displayed when I position the cursor over an MP4/AAC file, nor is there any when I right-click an MP4/AAC file and select Edit Tag from the menu.

I first became aware of this problem when I tried to import an MP4/AAC file that I'd converted using DMC into iTunes. The file would not play nor would any of the tag information display. After this occured I tried to edit the tag by right-clicking the file and discovered there was no tag information. The file was correctly named with an extension of .m4a.

Subsequent to the above I uninstalled the AAC and MP4 codecs and reinstalled the current versions posted on the website and tried everything again. I experienced the same results: no tag info and iTunes wouldn't play the file.

My source files are lossless WMAs created using WMP9. I've also installed the WMA codecs from the website.

**Spoon** · November 29, 2003, 11:26 PM

Re: No Tag Info w/ MP4/AAC Codec

As a matter of interest, convert to mp3, are the tags copied across?

**jp63670** · November 30, 2003, 03:24 AM

Re: No Tag Info w/ MP4/AAC Codec

Yes, if I convert to MP3, the tags are copied across and recognized by iTunes.

I've done a bit more research on my end and have uncovered some more potentially useful information. First, some background: I've got two computers; one on which DMC was installed after iTunes and one on which DMC was installed before. On the first computer no tag information is displayed, either by holding the cursor over or right-clicking and selecting EDIT TAG, for an MP4 file. However, the same file on the second machine displays tag information in both cases for the very same file. I get this result whether I've copied the MP4 file from one machine to another or I've accessed the file via a shared directory.

Second, I guess my original statement of the problem was incorrect in the respect that while iTunes won't display tag information for an MP4 file, it will import and play the file. An AAC file, on the other hand, is defiantely not liked by iTunes. Also, an MP3 or an AAC created in iTunes has tag info visible and editable through DMC.

My end goal is to batch convert all of my WMAs into MP4s for use on my iPod.

**Spoon** · November 30, 2003, 12:48 PM

Re: No Tag Info w/ MP4/AAC Codec

On the machine with no popup - run dMC Configuration and make sure that .mp4 is listed as an input decoder.

There are issues with iTunes showing tags from other programs - Apple are working on a fix.

**xja** · December 19, 2003, 03:01 AM

Re: No Tag Info w/ MP4/AAC Codec

I am having the same problem... no tag info appears in iTunes (I am converting from APE to M4A).

(I have installed dMC before iTunes.)

**Spoon** · December 20, 2003, 02:12 PM

Re: No Tag Info w/ MP4/AAC Codec

Apple released 4.2 the other day, have you tried that?

**xja** · December 22, 2003, 06:48 AM

Re: No Tag Info w/ MP4/AAC Codec

yes. problem still exists with iTunes 4.2. mp3 tags show up ok, but m4a tags do not.

**Spoon** · December 22, 2003, 06:55 PM

Re: No Tag Info w/ MP4/AAC Codec

If you hold the mouse over the file are the tags shown?

**xja** · December 24, 2003, 11:41 PM

Re: No Tag Info w/ MP4/AAC Codec

thanks for your quick responses. I won't be able to check your last suggestion until Fri or Sat of this week (I am away from my PC), so I will let you know then.

**ipodkiwi** · December 25, 2003, 01:34 PM

Re: No Tag Info w/ MP4/AAC Codec

I have APE files that were converted to MP4/AAC using latest beta dbPowerAmp Music Converter. I had problems with blank tags until I reinstalled using latest versions of db apps following Spoon's instructions in a response to my hydrogenaudio post (under iPodKiwi).

I'm playing around with latest iTunes 4.2.0.72. Tags show up fine when I hold the mouse over m4a files created with db apps (shows dBpowerAMP at bottom of tag). No info from that tag shows up in iTunes though. If I transfer that file to iPod using iTunes it also misses all tag info.

If I create a new m4a file straight from a CD using iTunes the tags also show up fine when I hold the mouse over them (still shows dbPowerAMP at bottom of tag created by iTunes). The info from an iTunes-created tag shows up fine in ITunes.

iTunes tag displays identical info for the 12 lines 'File' through to 'Codec'. Then ITunes tag starts next section with 'TITLE' (db one starts with 'Artist'). ITunes tag includes an extra 7 lines in the last section, such as 'TEMPO' and 'iTunes_CDDB_IDs'.

**iPodKiwi** · December 25, 2003, 01:58 PM

Re: No Tag Info w/ MP4/AAC Codec

Well that was weird. I now have an m4a file created using dbPowerAMP Music Converter running fine in ITunes 4.2 (and displaying all correct tag info). It also transferred to my iPod with all tag info intact.

I copied the dBPowerAMP-created file to my iTunes music folder. The iTunes helper service immediately stuck it in an 'Unknown Artist' folder. I right-clicked on the file and used 'Edit Tag'. I added a new element called 'TITLE' and set the title of the song. The minute I clicked on 'OK' the iTunes helper service grabbed the file and created the correct Artist and Album folders and move the m4a file there. I opened it in iTunes and all tag info was displayed correctly. I copied it to the iPod (using iTunes) and all tag info is displayed correctly on the iPod and it plays file too.

Any idea why that suddenly worked ?

**Spoon** · December 26, 2003, 04:12 PM

Re: No Tag Info w/ MP4/AAC Codec

I think it is a bug in iTunes, it seems to only like the tags written in a certain order (ie Artist, Title, etc) - if you convert a CD to mp4 then rename to m4a then I think it will accept it. When going from say an APE file, the tag might be in a different order, it is very poor programming of Apple.

**iPodKiwi** · December 28, 2003, 03:00 AM

iTunes and MP4 Tags

I've done a bit more experimenting and I now have about 4,500 MP4's running in iTunes with proper tagging (and working great on the iPod too).

It turns out that all I need to do is make ANY change to the tags created with dbPowerAMP and iTunes seems to work out the rest. I just selected all my files in MP3TAG (any mass tagger would do) and filled in the Comments section of the tag with 'Re-tagged for iTunes'. As soon as that was done I could hold the mouse over one of the MP4 files and see the bottom part of the tag with field names in capitals, which looks more like the format that iTunes seems to like (ARTIST is still first in the list).

I'm not sure if there is a new dll somewhere that did that (maybe from iTunes ?) but once iTunes saw the modified tags it grabbed everything and imported it into its library with full tag info.

Now I just let iTunes manage everything and it keeps track of how many times I have played each track on my iPod, what my personal preferences are etc. I just drop it in the dock and it synchs with whatever new stuff I have on the PC automatically. Letting go of the 'control' over how files are stored/named etc was a bit tough but life is a lot simpler now and I don't have to think about whether I have copied new tracks over to the iPod - it is always in synch now. The album art/cover bit is pretty cool too.