Export overwrite WAV

[muel]

Hi there!
The Bug described in 1.3.7 as: # Export as WAV could be corrupted if overwriting to same file seems not to be solved.
I just edited some wav files - then exported it again with the same name - overwriting the existing file.
Now my interviews mainly consist on short bits of the same words over and over again (see pic).
It's all gone. It sucks. I have to travel again.
There is no solution to it, is there? (Except: Backup!, I know and I blame myself)

[Gale Andrews]

The Bug described in 1.3.7 as: # Export as WAV could be corrupted if overwriting to same file seems not to be solved.
I just edited some wav files - then exported it again with the same name - overwriting the existing file.
Now my interviews mainly consist on short bits of the same words over and over again (see pic).
It's all gone. It sucks. I have to travel again.
There is no solution to it, is there? (Except: Backup!, I know and I blame myself)

The current Beta is 1.3.13:
http://audacity.googlecode.com/files/au ... 1.3.13.dmg

What version of Audacity are you using? You can check at Audacity > About Audacity.

If when you imported the WAV, your Import / Export Preferences were set to "Read uncompressed audio files directly" (which was default prior to 1.3.13), then when you exported Audacity will create a backup of the original WAV file with "-old1" suffix attached to the end of the original file name.

If you saved a project (.aup) you can re-open the project.

If you are using 1.3.13 then can you give us some ideas how we might make the bug happen. How long were the Audacity tracks and how many tracks were there? DId you have a selection in the track, if so where was it. Did you use File > Export or File > Export Selection?



Gale

[kozikowski]

It's all gone. It sucks.

Which is why you never, ever, ever record over or "step on" original live recorded sound files.

Those get duplicated onto backup media and saved somewhere safe. As you produce or edit your work, you can save it as progressively increasing backup filenames. MyShow1, MyShow2, etc. You can do this as Audacity Projects, or you can Export WAV files as you go. WAVs can take longer, but Projects, as you're finding out, can have health problems.

Nobody will be shocked if you make a mistake or have computer problems and need to do an edit or make up some work. Happens all the time. But nobody is going to want to do a performance again because you no longer have the original shoot, anywhere, in any form.

Koz

[muel]

Thanks for the reply!
I never use projects, worked on original file, no copy.

If you are using 1.3.13 then can you give us some ideas how we might make the bug happen. How long were the Audacity tracks and how many tracks were there? DId you have a selection in the track, if so where was it. Did you use File > Export or File > Export Selection?

Using 1.3.13, Mac OS 10.4, Export whole file, overwriting.
I think it happened only to files of 10-15 mins, shorter files not. Happened twice.
I had free space on my harddisk around 2 gigs (80gb disk). This the problem?
I swear I will always rename files in future. And maybe I should consider backups...

[kozikowski]

2GB is the approximate length of a two hour, very high quality, stereo show. That's not counting effects, UNDO and layers of filters and export final sound file.

So no, that's not even remotely enough drive space. The fuzzy number we use for editing is 15% to 20% free drive space -- after you load the show. If you have a smaller drive, it may go up.

That's assuming error-free, defragmented drive space. Audacity will not run into a fragmented drive.

Koz

[Gale Andrews]

To put some detail on Koz's figures, with 2 GB of disk space - if you import a 15 minute WAV at Audacity's default 32-bit float quality and do just five edits on the whole track, then you only have 200 MB left.

So if you can't clean up temporary files or otherwise prune disk space, consider clicking Audacity > Preferences: Quality and changing "Default Sample Format" to 16-bit. Then you can do 10 edits on the whole track before running down to 200 MB. After processing each file, do File > Close to clear out the Audacity temporary folder.

Audacity 1.3.12 or later warns you if you export WAV or AIFF and the exported file is not the same length as what you were trying to export. If it runs out of disk space when exporting, It will truncate the export to a safe length. So if you did not see that message, you did not run out of space on the export. From my tests on Windows, if the data in the project is correct, it will be correct in the export (just cut short if there is insufficient space to complete the export).

However having just deliberately done an edit in 1.3.13 that I knew I did not have space for, Audacity definitely corrupts the project data (for example, waveforms with repeated fragments or silenced waveforms). That edit seems to leave more space remaining than there was before the edit, which would allow a corrupted file to be completely exported. This isn't anything to do with the overwriting issue in 1.3.7, it's just not warning that it has run out of space and handling it incorrectly.

I haven't tested yet, but 1.2 I believe did warn in a crude way with incessant dialogue boxes if it ran out of editing space. There is I think no harm done in 1.3.13 if you are zoomed in enough to notice the problem and undo the edit, but there is that *if*.




Gale