Recovering audio apparently 'lost' via full disk

[JeffB]

Hello,

I saw the "crash recovery page" in the Wiki but want to double check here before I mess anything up.

I had to leave before a basketball tournament game started, so I used the Timer Record feature. I saved the project while it was still empty, but I was apparently too low on available disk space and by the time I got home the file showed a flatline in Audacity with no sound.

The folder contains the .aup file, and 11 sub-folders containing 2,423 files taking up 2.4 GB on disk. But when I click on that .aup file it still opens up with the flatline and no sound.

I recorded it in the 1.3.13 Beta version of Audacity and it didn't ask me if I wanted to try and recover any of the data.

Any help or recommendations would be appreciated.

[steve]

If you now have the space to do so, make a backup copy of the complete Audacity _data folder (could be onto a DVD).
The chances of manual recovery are not great, but you may be lucky.
The "Crash Recovery" page on the wiki is the best source of information re. recovering that we have.

[JeffB]

If you now have the space to do so, make a backup copy of the complete Audacity _data folder (could be onto a DVD).
The chances of manual recovery are not great, but you may be lucky.
The "Crash Recovery" page on the wiki is the best source of information re. recovering that we have.

Thank you.

It looks like I may be out of luck, but have a few followup questions, just in case...

I made a backup and freed up some space on the original drive, opened Audacity and imported the files in the first folder in the data folder. I ended up with a lot of tracks, but all of them were just a straight line with no sounds when I attempted to play any of them.

But I figured the files must not have been empty or it wouldn't have added up to 2+ GB in the folders. So I imported the .aup file from the original folder, which had to be done as "raw data". That track went to the bottom. )See the screenshot below.)



Am I completely out of luck, or do I need to move that track up, &/or import the other 10 files of data first?

I'm not sure how it all works, but in my mind I pictured Audacity as storing each of the 10 second sound bytes until it just ran out of storage space. Is this incorrect? Or does it need some sort of valid end file that explains how to recompile the sound bytes correctly?

[steve]

The .aup files don't contain audio data.
The files that contain the data are all of the little .au files (probably thousands of them).
This article will explain how an Audacity Project is constructed: http://manual.audacityteam.org/man/Audacity_Projects

What you'll probably need to do is to find which are the oldest .au files in the Project _data folder and see if they will open (if they are not damaged, Audacity should be able to Import them as audio files).

[Gale Andrews]

Further to Steve's reply made while I was typing, the garbage characters in "Audio Position" do not look hopeful, and you seem to be saying you imported from the first folder that had .au files. From what I recall from testing Audacity Beta some time ago, if Audacity runs out of space while recording it tends to carry on recording by overwriting from the start of the recording.

If you had valid data in the .au files you would (as the Crash Recovery page says) sort them into time order, rename them alphanumerically then piece (say) 1000 at a time together using the 1.2 crash recovery utility.

How long did you set the Timer Record feature to record for? This feature obviously did not work as intended. And when you got home, what happened? Was Audacity still recording silence but you could stop recording? Was the entire project flat lined then? If you saved the project like that, there is no point investigating further - you saved silence.

Do you (or did you have) almost no space on the drive where the 2.4 GB is stored (or a disk quota operating on it that limits space usage)?



Gale

[JeffB]

Further to Steve's reply made while I was typing, the garbage characters in "Audio Position" do not look hopeful, and you seem to be saying you imported from the first folder that had .au files. From what I recall from testing Audacity Beta some time ago, if Audacity runs out of space while recording it tends to carry on recording by overwriting from the start of the recording.

Bummer. I was afraid it was something like that.

If you had valid data in the .au files you would (as the Crash Recovery page says) sort them into time order, rename them alphanumerically then piece (say) 1000 at a time together using the 1.2 crash recovery utility.

I was hoping they were already in time order. The folders were numbered that way & I started with the first one. The individual files within that folder looked like they were numbered in consecutive order as well, though I'm not absolutely positive as they had some alpha characters mixed in with the numbers. But it looked to me like they were probably numbered consecutively in time order. If they were out of order, wouldn't it still have sound, but just be out of order, similar to a bad VoIP call?

How long did you set the Timer Record feature to record for? This feature obviously did not work as intended. And when you got home, what happened? Was Audacity still recording silence but you could stop recording? Was the entire project flat lined then? If you saved the project like that, there is no point investigating further - you saved silence.

I set it for 4 hours. They often have about a 1 hour pre-game show, and I figured it would be about 2 hours for the game, especially if it went into overtime or something, and then another hour for the post-game show. I figured it might be a bit of overkill, but would rather have deleted excess commercials & songs etc. at the end, rather than miss part of an interview or something. It's worked pretty well for me in the past, though I've had a couple of times where I apparently lost the radio stream. The stream was still going, though, when I got home. The recording had reached it's 4 hour time limit, though and it was flat-lined. I was hoping that was just the end or something, but unfortunately, it was that way all the way to the beginning.

I have have run out of room before and it did the flat line thing, but I was there. It took me awhile to figure out what the problem was, but I stopped it and Audacity had asked if I wanted to have it try to recover lost files and it has been able to do so at times.

Do you (or did you have) almost no space on the drive where the 2.4 GB is stored (or a disk quota operating on it that limits space usage)?

I knew I was cutting it close on the disk space, but my wife decided she wanted to go visit her father and was really rushing me so we could get there in time to go for a walk in the park & get back in time to eat. We were having our big basketball game in the finals of our conference tournament... our last in that conference as we are leaving next year, so it was a rather historic game. We won the tournament, by the way, and there was a lot of celebration and probably some good interviews after the game, which is why I'm more interested in trying to resurrect / save whatever I can.

I had done a disk cleanup, a couple of days before, just before I recorded the semi-final game. I think there was about 3.8 GB left or so before I recorded that game, and I think it used a little over 2 GB and I was stopping the recording at most commercials. The next day, I cleaned it up, taking out residual parts of commercials and closing up any blank spaces etc. & exported it as an .mp3 intending to upload the .mp3 to MediaFire and then delete that recording. Unfortunately, MediaFire kept having errors in the upload and my wife was hounding me to get out the door, so I put the Audacity files in the recycle bin & kept the .mp3 file of that game. I'm not sure if the recycle bin automatically frees up that space, though, even if it's needed.

In any event, there was a little space still on the hard drive, but I don't remember if it was 50 + MB or something like 506 MB. It seems to me like it may have been closer to the latter, but I could be wrong. I think the hard drive is like 103 GB.

Thanks again for the replies.

[JeffB]

The .aup files don't contain audio data.
The files that contain the data are all of the little .au files (probably thousands of them).
This article will explain how an Audacity Project is constructed: http://manual.audacityteam.org/man/Audacity_Projects

Thanks. I don't believe I've read that article before, but will try to make the time to do so tomorrow. I had kind of figured that out the hard way in the past, when I moved projects or renamed files and it wouldn't work any more. I don't believe that's the problem this time, though.

What you'll probably need to do is to find which are the oldest .au files in the Project _data folder and see if they will open (if they are not damaged, Audacity should be able to Import them as audio files).

I didn't do the sort thing & hoped by taking the files in the 1st sub-folder, d00, in the order listed, which seemed to me to be in order from oldest to newest, that they would already be in order. But I guess if it went on some sort of a loop when it ran out of disk space it may have overwritten some of those earlier files.

I imported every file in that folder and they were all flat lined with no sound. According to the folder properties, however, it said there were 256 files and it took up 260 MB "size on disk".

1. Would it take up that much disk space if it had been recorded as silence?
2. Would it still play if the individual files were imported without the .aup file? If not, do I need to import it first, & then the .au files?
3. If one or more were out of order would it just not play, or would it still have sound but have the 10 second sound bytes all out of order?

I had been gifted this laptop not very long ago and am still trying to get used to the Vista operating system. I just figured out how to unhide the file types, but can't seem to find out how to do a sort by date/time. It's not listed in the explorer view as far as I can tell. I did just hover the cursor over the files and it seemed at first like they may have been in order, but unfortunately they are not. I found some that were out of order. I've tried clicking on the sort button, but don't see an option to sort them in date/time order. I'll have to ask my brother-in-law how to do it. Hopefully he knows, he's still using XP as well & got this from his mother-in-law. I'll try resorting it & try it again.

Thanks again for your time and your help.

[steve]

1. Would it take up that much disk space if it had been recorded as silence?

Yes. Uncompressed audio holds the values of every audio sample. By default Audacity saves the audio data in 32-bit float format, so there are 4 bytes of data for every audio sample, so at a sample rate of 44.1 kHz that is 44100 x 4 bytes per second for a mono track, or 44100 x 4 x 2 = 352800 bytes per second.

2. Would it still play if the individual files were imported without the .aup file?

Undamaged .au files can be imported into Audacity and will play normally.

3. If one or more were out of order would it just not play, or would it still have sound but have the 10 second sound bytes all out of order?

Each .au file is a small block of audio data. If you import them and place them end-to-end they will play in the order that you place them. The file names are randomised so you will need to use the file date to work out the correct order.

I just figured out how to unhide the file types, but can't seem to find out how to do a sort by date/time.

I don't use Windows very often, but perhaps this tool will help: http://zabkat.com/
If you look round their web site there is a "free for personal use" version, which has a few advanced features missing, but is still a very good file management tool.

[JeffB]

1. Would it take up that much disk space if it had been recorded as silence?

Yes. Uncompressed audio holds the values of every audio sample. By default Audacity saves the audio data in 32-bit float format, so there are 4 bytes of data for every audio sample, so at a sample rate of 44.1 kHz that is 44100 x 4 bytes per second for a mono track, or 44100 x 4 x 2 = 352800 bytes per second.

2. Would it still play if the individual files were imported without the .aup file?

Undamaged .au files can be imported into Audacity and will play normally.

Well that doesn't sound good then, at least for that first folder.

3. If one or more were out of order would it just not play, or would it still have sound but have the 10 second sound bytes all out of order?

Each .au file is a small block of audio data. If you import them and place them end-to-end they will play in the order that you place them. The file names are randomised so you will need to use the file date to work out the correct order.

Since at least that first folder of data was all flat-lined and silence that apparently means it is toast, not just out of order. Hopefully I can salvage some of the others, though.

I just figured out how to unhide the file types, but can't seem to find out how to do a sort by date/time.

I don't use Windows very often, but perhaps this tool will help: http://zabkat.com/
If you look round their web site there is a "free for personal use" version, which has a few advanced features missing, but is still a very good file management tool.

Mucho thanks for the heads up on that zabkat file manager utility. That looks like a very nice piece of software to have even if I can't salvage much from my recording, if this review is to be believed. At least it makes me feel a little better about my ineptitude in using Vista's Explorer. The experts think it sucks too.

I guess that's one of the reasons you don't use Windows much, eh? Learning how to install Linux on my computers is on my wish list. I think I'd really like it, but don't want to crash a computer trying to do so, especially since I don't have any of the original install disks.

[PGA]

Mucho thanks for the heads up on that zabkat file manager utility... At least it makes me feel a little better about my ineptitude in using Vista's Explorer. The experts think it sucks too...

Not necessarily. As with all complex software products, it repays time spent learning about it. Did you instantly know everything about Audacity the very first time you used it? No, you learned how to do the things that you wanted to do. And if you are like me, you are still learning new techniques and skills. Windows Explorer is customizable just like any other piece of software. It's "bad press" is more about folks not taking the trouble to learn how to use this File Manager product. Partly that might be due to them not fully understanding the need for good file management processes. My experience during my working life (30 years in IT Technical Support) was that folks who were tidy by nature used Explorer effectively; those who were untidy by nature didn't!

You can, on a folder by folder basis, change the information that is displayed and decide on which of the columns the sort (ascending or descending) is to be applied. Try this:
- At the top of the Explorer display, where the column names are display, right-click in the free space at the end of that line
- Select an item to be displayed by "ticking" it
- Provided you chose an item that has some data associated with it, now click the column title and observe the order of the items change as the sort order changes
- Click the column title a second time to reverse the sort order

Setting up a specific folder to show what you want, in the order that you want it, can be time consuming; but it is possible and, for those who are of a tidy nature, it is useful to have things just as you want them.

Peter