-Brading Software Message Board
+--Forum: Mp3/Tag Studio Support and Bug Reports
+---Topic: VBR errors appear when generating V1 tags started by calberga
Posted by: calberga on July 23 2006,16:31
Here is a puzzle for you when you return, all rested, from your holiday.
I have been encountering a rather large number of files which start out with only V2 tags. When I perform any (? I haven't really tried them ALL) of the operations which force syncing, such as a "tag from file names", the V1 tags are added, as is expected.
If I use "browse & edit" on these file initially, the length and frames values are shown in black, i.e. mp3/tag doesn't one detect a VBR error. However, after the operation which adds the V1 tags the length and frames values are shown in red. This is easily fixed with the VBR repair tool, but it seems odd that mp3/tag operation should either cause this error or unmask a hidden error.
I have saved several of the offending files in their original state, and can send you one or more if you wish to wallow in the bits.
Posted by: calberga on July 23 2006,16:51
As a minimal case, I have just observed that simply changing the value of a tag in "browse & edit", and writing the result will trigger the error is that single file.
Posted by: Magnus Brading on July 28 2006,11:36
This is known, and "intended", well sorta... The problem is that the exact file size of the file is stored inside the VBR header. If an ID3v1 tag or ID3v2 tag is added (i.e. set while not previously existing at all, which also means that it does not only happen for ID3v1 tags, which also means it was only a coincidence that your files already contained an ID3v2 tag, but not an ID3v1 tag, which lead you to your conclusion about ID3v1 tags), the filesize is increased, and hence the filesize inside the VBR header is no longer correct, so it needs a subsequent update with the VBR repair tool. The size change is so small that it will not affect any VBR playback or seeking though, but sure, its annoying, I agree.
And I know, I really should add an option for auto-updating of the VBR header for these situations, just been too lazy.
*spanking myself* 
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