Corrupted Audacity Files

[TonyVA408]

[Audacity version and system info appear below.]

Have there been any reports of Audacity files being corrupted? I've been using this version for a few months and for the first time ever, several of my saved project files are getting corrupted. I think the issue might be related to using the Edit > Silence Audio function.

Some background -- I don't think my project is especially challenging. I'm using only four or five tracks that are just three or four minutes long. The program doesn't crash and there is no error displayed at any time. However, saving, closing, and reopening certain project files has resulted in certain tracks being inexplicably changed.

This problem has occurred several times in recent weeks and there is just one common thread to all the project files that have been affected by this problem: The affected tracks had portions where I had used the Edit > Silence Audio function. If I had to guess, it seems Audacity gets confused about the track segments that should be silenced, and upon re-opening a saved file, completely different segments are found to be silenced. In the most recent case, it seems -- meaning I'm not 100% sure -- the portion that was silenced became unsilenced AND the audio data on that track preceding the silenced segment then becomes silenced. The audio data that follows the portion I had silenced seems unaffected.

Any help regarding this issue would be greatly appreciated.

I'm using the Windows version of Audacity 1.3.13-beta with a build date of April 6, 2011, and I'm running it on a Vista Home Premium system.

[Gale Andrews]

Thanks for the report and sorry for the problem. Were any of these projects originally created in Audacity 1.2?

To begin with, please attach the .aup files for the projects that became corrupted when you reopened them, plus log files for each. You can get the log files by clicking Help > Show Log, then Log > Save. Put everything in a zip file and attach it by using "Upload attachment" underneath the message Preview/Submit buttons where you post. The attachment limit is 1 MB, but you could make separate zips if necessary.

As background, there is an occasional problem with "missing" or "orphaned" file errors when reopening projects that may or may not lead to data loss:
http://wiki.audacityteam.org/wiki/Relea ... at_Release

There is another bug recently discovered where Audacity can create (or set up references to) .au internal data files that are longer than the .aup project file permits. To cut a long story short, Audacity will delete these without warning, leaving empty audio. This could be partly what you are seeing, but we need to see the .aup files to judge that.

I would recommend exporting as WAV before you close the project which will give you a backup. If you need the tracks to be separate WAVs, select each track in turn then FIle > Export Selection.



Gale

[TonyVA408]

Were any of these projects originally created in Audacity 1.2?

Gale ... Thank you for your very thorough and prompt reply. To answer your first question, no, the affected projects were started and maintained entirely within version 1.3.13-beta with a build date of April 6, 2011. I should add that after noticing the changed/corrupted tracks, I tried to open my affected project using an earlier version of Audacity with the hope that the "lost" data might be recovered, but the program promptly complained and prevented me from working on a version 1.3.13 project using an earlier Audacity version.

I also appreciate that you brought my attention to the Known Issues info regarding the Missing Audio Data Blockfile(s) errors. In fact, I accidentally misled you in my initial post as I said that I saw no error messages. In fact, what I should have said is that Audacity doesn't crash, but I did see program messages offering the option to "Treat missing audio as silence" or "Continue without deleting" the orphans.

The files you requested are attached. I would just like to emphasize ... To the best of my recollection, the common thread for all the problems I experienced seems to be with projects where I had used the Edit > Silence Audio function.

My warmest thanks again, Gale. We all wish you luck with resolving this issue and with getting the next release out the door.

[Gale Andrews]

Thanks, Tony.

I don't see any evidence in the .aup file of .au files that are longer than they should be. I do see you have a mono file "CBS_NBA_85_montage" which seems to be 16-bit (making the permitted length of the .au files greater) but all the other un-named tracks are 32-bit. Does "CBS_NBA_85_montage" show as 16-bit above the mute/solo buttons of the track, and do the other tracks show as 32-bit? Are these tracks all recordings, and did you change the Default Sample Format in the Quality Preferences during the project?

What I should have said is that Audacity doesn't crash, but I did see program messages offering the option to "Treat missing audio as silence" or "Continue without deleting" the orphans.

Those two options relate to missing blockfiles and orphans respectively. Did you see two separate windows, one asking about missing blockfiles and another about orphan files? Help > Show Log should have listed missing and orphan files, but the log you attached only refers to gaps in the project file. This probably suggests Audacity has deleted files and that you would not see any missing or orphan errors if you opened the project again. Is that correct?

Do you still have the other projects that were affected? If so it might be worth a look at the .aup files.

As well as exporting WAVs before you close a project, it might be useful after closing it if you created a new folder then copy the .aup file and _data folder for the project into that new folder. If the project then fails when opened from its original folder we would at least be able to replicate it failing if you gave us the new folder.


Thanks


Gale

[TonyVA408]

Does "CBS_NBA_85_montage" show as 16-bit above the mute/solo buttons of the track, and do the other tracks show as 32-bit?

No, Gale. In fact, ALL the tracks in that project presently appear as "32-bit float," and all at 48,000 Hz, by the way.

Are these tracks all recordings, and did you change the Default Sample Format in the Quality Preferences during the project?

As you asked whether these tracks are recordings, I guess you mean, "Did I record them in Audacity." No. The mono track, "CBS_NBA_85_montage," is actually an import from an MPG video file. I believe the other other tracks in that project were created using the Tracks > Add New function and the audio content was pasted into the tracks from other tracks that have since been removed from the project.

As for your question regarding the Default Sample Format in the Quality Preferences, unfortunately I cannot recall. I may have fiddled with that at one time or another, but don't know for sure.

No, I don't have the other project that was affected. As I thought the issue was just a one-time thing, I started over, discarding the original project.

As for your remaining questions, I sincerely apologize and regret that I'm not able to accurately address them. I assure you ... If I could have foreseen these detailed questions (which I very much appreciate, by the way), I would have noted things more carefully. Saying any more about the problems I experienced thus far would be worth only as much as wild guesses and I surely do not want to lead you astray with incorrect/inaccurate information.

If time permits, I'll try to duplicate the circumstances leading to the errors I experienced and I'll be sure to report back better prepared to address these types of issues more thoroughly and with greater accuracy.

Thank you again for your hard work, Gale.

Tony

[Gale Andrews]

Does "CBS_NBA_85_montage" show as 16-bit above the mute/solo buttons of the track, and do the other tracks show as 32-bit?

No, Gale. In fact, ALL the tracks in that project presently appear as "32-bit float," and all at 48,000 Hz, by the way...
The mono track, "CBS_NBA_85_montage," is actually an import from an MPG video file.

I think that makes sense. FFmpeg would have imported the audio from the video file at 16-bit even if your Quality preferences were at default 32-bit float because FFmpeg has that limitation. When you reopen the project, the 16=bit video track would still open at 32-bit resolution if your Quality Preferences were set to 32-bit.

But can you confirm if you open this project now, there are no "missing" or "orphan" warnings that pop up in front of the project? If you are able to, I think it might still be helpful if you can zip up the .aup file and its _data folder and upload it to a free file transfer service such as:

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

then give us the web address where we can download it. Then we would know for sure if there is anything we can deduce from it or not.

If time permits, I'll try to duplicate the circumstances leading to the errors I experienced and I'll be sure to report back better prepared to address these types of issues more thoroughly and with greater accuracy.

That would be helpful.

Don't forget that probably the most helpful thing of all you can do after closing any project is to create a new folder, then copy the .aup file and _data folder for the project into that new folder. If the original project fails on reopen, we have your copy we can reproduce the problem on.

Even better, you could create an additional copy *before* closing as well, because there's a suspicion that problems could occur when closing the project as well as when re-opening it. We can test both scenarios with "before close" and "after close" copies. I know it's a lot to ask, so thanks anyway.



Gale