Metadata being removed on Export to MP3

[sunrunner]

There seems to be a problem when chaining multiple files for normalizing and export to MP3 which originated as an MP3 file. The Year tag is overwritten from having a value to a blank tag. All other tags translate correctly. When exporting to MP3 individually under the same conditions using either export or export to selection, under file item of the menu bar, all tag data is written correctly.

The version of Audacity is Windows 1.3.12 Beta
The version of Windows is Windows XP SP3

Steps to reproduce:

1:Under Edit Chain on the file menu setup the following chain
Chain Name :Normalize All

Chain Commands:

Num Command Parameters
01 Normalize ApplyGain=yes,RemoveDCOffset =yes,Level=3.000000
02 ExportMP3
03 -End-

2. Enter the MetaData using the standard template under file menu " Open MetaData Editor" which are scheduled to be chained. Any other fields in the Meta data editor are left blank. Below is a sample of the type of meta data which is being entered.

Artist Name : Music Student Recital
Track Title : Von Brauns Concerto
Album Title : Van Amson's Auditorium 20100722
Year :2010
Genre :Classical
Band : Music Student Recital

3. Go to Apply Chain under the file menu and choose the chain "Normalize All"
from the pick box.
4. Click the button on the dialog box "Apply to files"
5. In the dialog box navigate and choose the files which need to be chained.
6. Once files are choosen click the "Open" button on the dialog box.
7. The chain process starts with no errors detected.
8. Once the chain process is complete check either Windows explorer or open the file in Audacity
and the year tag has been wiped out to a blank.

After playing around with the Chain routine I found that if the Track Title and Album Tittle are the same in the metadata, the year tag is not rewritten to blank.

Artist Name : Music Student Recital
Track Title : Von Brauns Concerto
Album Title : Von Brauns Concerto
Year : 2010
Genre : Classical
Band : Music Student Recital

[Gale Andrews]

Thanks for all the steps. Assuming the original MP3 that you apply the chain to was created in Audacity, I wasn't able to reproduce it in 1.3.13 alpha on Windows 7 with the exact metadata you state (either entering the exact fields you quote into an empty metadata window, or saving and loading them as a template, before exporting the MP3). I only tried applying the chain to one MP3. I tried both with the Metadata Editor empty before applying the chain, and containing your text before applying it (even though that shouldn't matter- the existing metadata should be overwritten by that in the import).

I can seemingly reproduce the problem if the MP3 the chain is being applied to was not created by Audacity. However if I make the Track Title and Album Title the same in Explorer, the bug still occurs. Perhaps you made them the same in Audacity?

Although I can seemingly reproduce it now, an example MP3 that has the year tag stripped out if you apply a Normalize/ExportMP3 chain to it would still be useful to test against. You can upload a short MP3 up to 1 MB (one minute at 128 kbps) in your reply (click "Upload Attachment" underneath the Preview/Post Message buttons). If it's larger, please upload it to a free file transfer service such as:

http://www.yousendit.com
http://www.megaupload.com
http://www.sendspace.com

and give us the web address where we can download it.


Gale

[sunrunner]

Thank you for your reply. All the MP3 files in question were created in Nero 8 and the MP3 Tags were created in an application called Tag and Rename v 3.5.6 since Nero 8's WavePad application does not support the writing of MP3 tags.

This weekend I recorded another student concert and split apart the individual music sections. Then I added MP3 tags using Audacity 1.3.2 beta to each track created. The files were saved using Audacity's Lame plug in to the MP3 format using default options. After that I continued on to apply normalization using the chain feature to the individual tracks. This time the MP3 tags data held as originally typed after normalization.

I can only assume that Nero 8, Tag and Rename v 3.5.6 or a combination of using both to create MP3 tags caused this defect to occur in Audacity. I've tested the Chain command in Windows XP SP3, Vista SP2, and Windows 7 and all operating systems worked in exactly the same fashion with no removal of data observed

To correct the older files which had the year tag removed I cleared out all the existing MP3 tag entries one file at time and re-wrote the tag text making sure that empty text fields had no extranous spaces by selecting the text box and hitting the delete key. After that I resaved and applied normalization through the chain command to the edited files. All the MP3 data stayed intact this time.

Unfortunately I was not watching it and overwrote the bad data in the MP3 tags so at this time I have no files to send with the defect.