Why does conversion from WAV to AIFF change ID3 tag

I converted some files from WAV to AIFF and I was surprised that the ID3 tag had changed, I assumed it would be left alone seeing as both formats support it.

Changes are:
- The [B]UFID[/B] frame has not been transferred
- The [b]IPLS[/b] frame has not been transferred
- All fields are stored as [B]UTF16[/B] instead of [B]Ansi[/B], even though all values are encodable as Ansi
- The value of the [B]TMED[/B] field has changed from[B] CD[/B] to [B]CD >> CD (Lossless) [WAV][/B]
- Has added a [B]TXXX:Commissioned[/B] field that is set to the Record label
- Has added [B]aaar[/B] field set to artist name
- Converted multi value Composer and Conductor fields to a single value separated by '/'

So:
- Is there a way to convert the file and leave the ID3 tag alone ?
- What options are actually being used as I cant see any options for conversion to AIFF ?

There is no way to specify the tag is not touched, sorry.

- and theres no way to stop fields getting lost when it is rewritten either ?
- what option can I use to stop it writing as unicode16

If there are unsupported fields then they will not be read or preserved.

UTF16 is always written to AIFF, we believe this is the standard which apple created and have always followed.

Is there a list of what fields DbPowermap [B]does [/B]support ?
There are certainly no issues with iTunes using ID3 with ansi values with AIFF, AIFF properly supports ID3v23 (and ID3v22 and ID3v24) not a subset version of ID3 so I can see see no reason to force use of Unicode16

We write AIFF files exactly as iTunes does.

I do not have a list of the fields at hand, however if we are missing fields, they can be added in future versions.

What I would most like to see is a ay to leave teh ID3 tag alone when converting form one format that supports ID3 to another.

ID3 tags are not independ from the music codec and file format.


Dat Ei

ID3 tags are completely unaware of their surroundings, so if a format supports ID3 then an ID3 tag can be added into the file from somewhere. MP3, WAV, AIF and DSF all support ID3 so it would make alot of sense to just take the ID3 tag as is rather than recreating it and losing lots of information as currently happens. Actually I could quite easily write a command line app to extract a tag from a file, and then another to add a tag into a file replacing what is currently there but I don't quite understand if there is way to plug into a dbpoweramp workflow