uploaded files loosing header information

[DotComMusic]

I'm a new PowWeb customer (three months now), and other than the recent repeated outages on cluster 07, I'm quite happy with the entire service here. But I've just discovered a problem which I never had on the servers at my previous provider.

Uploading audio files to my PowWeb space, I find that some of them are unable to be opened once they are downloaded off the server. The particular file which brought this to my attention was a SoundDesigner II type audio file. I tried it both with a file extension and without, and got the same results with both of those options. It was a 24bit mono audio file, but attempting to open the downloaded file it now appears to be a 16bit headerless data file. Which is unuseable. Something is stripping the header information out of the file.

I can create a .zip archive of the file, upload that, and then it still IS useable after downloading the archive and expanding it, but it will not always be practicle for me to do that with everything I upload. I have tried the upload with two different ftp clients, and also have uploaded it as both binary data and as text. Same results either way.

I contacted a friend who is also a PowWeb customer and asked him to try the process with a similar file uploaded to his space. He reported back with the very same (unuseable) results upon download.

Is this an issue which has come up before, for other users? What is the reason for this issue? And more importantly, what is the fix? How can I prevent this from happening to files I upload?

Cheers.
jb

[DotComMusic]

Interesting. I just opened up the downloaded file which will not open as an audio file, in a hex editor, and discovered that the resource fork has been removed.. so placing this file on my PowWeb server REMOVES the resource fork. Opening the one which came from the archived version, there indeed is a resource fork in that one.. which allows it to still function as a valid audio file.

This is not good, me thinks. I must admit that I'm pretty dumb when it comes to issues like this. Why do some servers remove the recource fork, while others don't (my previous one did not)? And how do other users here at PowWeb get around this issue?

[stevel]

Resource fork? Is this a Mac thing? You're FTPing to a Unix host, and it doesn't know resource forks. As long as you've transferred the file in "binary" mode in FTP, whatever bits your client sends are the bits that end up on the server. PowWeb is not "removing" anything (nor does it have the ability to do so.) You have to attack this from the side of your FTP client.

[DotComMusic]

Interesting.. Thanks for your response. I wonder why this was never an issue on my previous hosting provider's servers? As I said before, I'm dumb when it comes to server issues, so I'm not trying to cause any trouble here.. I'm just looking for solutions to a problem. Anything you can pass on to me to educate me would be appreciated.. I want to learn about this.

You say it is an issue with my ftp client? I'm using the same client which I always used to upload to my old server, where this issue never came up. I don't know what kind of system they used, but I'm quite confident that it was not a Mac server. Although, yes, I am on the Mac platform locally. But OSX is a Unix-based OS, so I'm a bit confused why I'm having a problem.

[stevel]

Perhaps tbonekkt will chime in, as he is a Mac user. I can't think of any way that a transfer to PowWeb's FTP server would remove information as long as you did the transfer in binary mode. OS X may be Unix-based, but its file system is not.

[tbonekkt]

What's the file you're trying to upload? I've never had this problem when using my PowerBook.

[DotComMusic]

Yo Tone.. a fellow Mac user. The file is an sdii 24bit mono audio file. It plays just fine in QuickTime before I upload it, but QT won't open it after downloading. The trashed file is here:
http://www.dotcommusic.com/ftp/forum-media/spike_22050.sd2

The archived version which still works on download is here:
http://www.dotcommusic.com/ftp/forum-media/spike_22050_sd2.zip

Check for yourself. If you can verify that the file in the archived version is playable, try uploading that file (the single audio file) as is to your server, and see if you can play it after you downloaded it again. I'd love to figure this out, as I am going to need to frequently put audio files on my space for others to download.

Thanks for checking..
jb

[stevel]

I can tell you that the file I download as the .sd2 is bit-for-bit the same as the one in the zip file.

[DotComMusic]

That's interesting. I wonder then why one of them will open for me as a valid audio file while the other one won't.

When I open the two in a hex editor, they indeed do appear to be the same. Except for the resource fork.. which contains the map of the file's sample rate and the bit depth and the overall length of the file. One file has that, while the other one does not. I'm able to copy that from the "good" file, paste it into the other one, and then it too will open properly. But that information is different for each and every file (because of the length of the file .. total number of samples contained in it) so it's not easy to simply recreate one for each file.

Tone, what were you able to discover? Anything?