HydrogenAudio

Lossy Audio Compression => MP3 => MP3 - General => Topic started by: Ronn on 2013-06-03 06:48:19

Title: Strange Characters In Tag
Post by: Ronn on 2013-06-03 06:48:19
Hello,

A buddy of mine found a disc with some MP3s burned on it. When we returned to the vehicle I played the disc in the Alpine receiver. All the tracks seem to play normally, but some of the tracks had tag problems. It didn't matter which tag was selected, YPO or some other YPx three letter combo was displayed.

Later when we returned home I check these "bad" tracks with Mp3 Tag Tools and WinAMP. Both apps showed available tags. Next I compared the "bad" tracks with "good" tracks in a Hex editor. I noticed that every problematic track the tag was preceded with two characters, ÿþ. The tracks that displayed properly in the vehicle were absent of these two characters. These two characters appear to be the source of the YPx that was displayed in the vehicle. What I'm wondering is:

Is there a purpose for preceding each tag with ÿþ?

Which program may have created these messed up tags?

Thanks.
Title: Strange Characters In Tag
Post by: Aleron Ives on 2013-06-03 07:50:48
The characters you are seeing are a Unicode byte order mark (BOM). Your MP3s were tagged using UTF-16 (Unicode Transform Format), rather than the ISO-8859-1 (so-called "Latin-1") character set. Because Unicode uses multiple bytes for individual characters, some programs require a BOM to determine the endianness of the values. The BOM 0xFE 0xFF is interpreted as ÿþ by text editors that expect the ISO-8859-1 character set to be used. The tags aren't necessarily broken, but not all MP3 players support Unicode ID3 tags. You can prevent the problem by re-tagging the MP3s in the ISO-8859-1 character set, which is more compatible (as long as the tags don't require Unicode characters, e.g. for song titles written in non-Western languages).
Title: Strange Characters In Tag
Post by: Ronn on 2013-06-03 16:29:03
Hello Aleron,

The text contained in the tags only used western language characters. I suppose whomever tagged the MP3s probably had no good reason to use UTF. The Alpine receiver is at least 8 years old and is probably choking on the rest of the text as soon as it encounters the ÿþ characters. I've only used Mp3 Tag Tools for tagging and never had a problem displaying tags in the Alpine until this disc showed up.

Thank you for the explanation.

Title: Strange Characters In Tag
Post by: AllanD on 2013-09-12 16:57:39
I'm just curious what make car stereo was having issues with the Unicode Tags?

I know that in the past my older Sony Car head units didn't "play nice" with Unicode.
(I haven't actually tested Unicode tags with my current MEX-DVD2200 multimedia deck)

so I uncheck "Always write Unicode" in my installations of Tagscanner