Bewildering avi corruption - any clues?

[Rasaraja]

Hello,

I have a very bewildering corrupt avi file problem that I can't seem to figure out, and doesn't seem to make sense.

I'm using PremierePro 1.5, capturing from a Mini DV camcorder thru a Canopus ACEDVio card via firewire. The capture drive is a LaCie 320GB (80GB free), connected via 400 Firewire. The Premiere Projects are using the Main Concept 2.4.1 codec.

Here's the problem that just started happening.

I capture to a few projects. Clips are 20 min long. Each project (5 of them) contain 4 to 5 20 min avi captures. I can work in the projects, go back and forth between them and all is ok - no problems.

The next day (or two), I open the projects and any one (or two) of the original captured clips have become corrupt. I run them thru GSpot and - yep - corrupt avi - size 0 bytes, and have to recapture those clips.

The only thing I could think of was to turn off Disk Caching on the capture drive, which might be the cause - but dunno for sure.

It doesn't seem to make any sense that one day the file is ok and the next, it's corrupt - when nothing's really been done to that original capture.

Anyone have any clues as to what might cause this?
This problem just started happening - has not happened in the past.

My base system has 2GB RAM, Athalon 2.1GHz processor.

Thanks in advance.

Ray K

[SLK001]

Could be the disk caching - I get the same problem when I improperly remove a flash drive (hasn't completely transfered everything to the drive). How are you turning off the computer? A normal shutdown should move the caches to the permanent storage.

Or, maybe a virus has clamped on to your system.

[Rasaraja]

Normal shutdown and no virus'

[Nelson37]

Can you save these projects and then immediately re-open them? Can you save these AVI caps as they are captured, to different directories?

It sounds like some part of the editing process is starting to write to that filename and then does not complete, or they are never saved at all. Project name same as filename, etc.

Is there any pattern to the disappearing file? First or last capture, etc?

Possible this is a mechanical HD problem but seems far to specific.

[Rasaraja]

That's the bewildering part. All appears to work as designed. I can save and reopen the projects, save the project(s), open another, work in that other project, reopen the other one, work in it, close Premiere, reopen it - all is ok. Plus, to my understanding, the original avi files do not get altered.

So all is ok with the originals. But the following day(s), any random avi get's magically corrupted - there's no pattern. It could be any random file in the capture sequence. File and project name(s) are all unique.

I've started making backup sub-folders and copy the captures to a bak after the capture, but that's a bit of a time and space waste.

It's definately got me scratching my head and am curious to see if it happens again with some new 'test' projects.

I also wonder if lower Hard Drive performance might be a factor - since I have 80GB free space on the 320GB drive.

[Nelson37]

Do this for test. Capture, then close Premiere. DO NOT OPEN IT AGAIN UNTIL AFTER TEST.

Verify ALL - not just some, but all - AVI files are OK by using another program, such as Vdub.

Ideally, do nothing else on the PC, or at least do not open Premiere, for any reason. Shutdown, restart, etc. Periodically check those files. Let it sit for a while, preferably same time period as when you usually notice the problem.

I would be extremely surprised if the files are verified OK after closing Premiere and then develop a defect without Premiere having been opened again. This would point to HD issue, or virus-like activity.

Assuming files still OK, backup all AVI and VERY CAREFULLY perform single operations and then close Premiere, then check AVI files in other app. This is to pinpoint the operation which fubars the file.

[Rasaraja]

Thanks for the troubleshooting tip Nelson.
I'll try this over the next few days.

[edDV]

It must have something to do with using the external drive. Here are some thoughts.

Where are you placing the temp scratch disk (work buffer)?

I find it most reliable to do the actual capture and editing on an internal capture drive (scratch drive on capture drive) and then use the external drive for project and working clip storage.

If you are just previewing the clips, I can't think of a reason why the capture files would be corrupted. If you are editing or filtering, the work is first done to the scratch buffer and only applied to the file if you save to the same file name. I always save to a different file name so that the original capture file is preserved.

It could be your scratch buffer write to the external drive is the source of the error.

[Rasaraja]

The captures go to the external drive.
The scratch disk for Audio & Video Previews go to an internal drive. The conformed audio also gows to the internal drive.

Oh and I just opened a project that was ok days ago and haven't touched it in days and one 20 min capture was bad. I tried a file repair app DivFix and it reported that the file was not a valid avi file. VDub reported that it could not detect file type.

[edDV]

I recommend you capture to an internal capture drive. It's much less risky. The file can then be transferred to the external drive for project storage. That kind of file copy is under OS control with error checking.

Scratch disk on the internal means that anything rendered there needs to be copied to the save drive. This adds considerable copy time and corruption can take place if your external drive isn't reliable.

Scratch disk should be on the same disk where you intend to save the file. Normally this is the internal video drive. It should not be on the OS partition.

Read through some of these forums for clues.

http://forums.creativecow.net/cgi-bin/new_read_post.cgi?forumid=3&postid=854958
http://forums.creativecow.net/cgi-bin/new_read_post.cgi?univpostid=822247&forumid=3&po...822247&pview=t

http://busca.adobe.com/search?site=AdobeCom&client=AdobeCom&filter=0&output=xml_no_dtd...rewire&x=0&y=0

[Rasaraja]

Ed,

That seems to make sense. In other words then, capture to an internal drive, have the scratch disks on that same drive, and then copy the captured file to the external drive. correct?

If so, I may shop for a larger internal drive. The external is 320GB. I have a non OS drive of 120GB and would like a little more room to work with.

Do you think pointing Premiere to the external drive would be ok after the files get copied over? Most of the projects I'm working with is a series of lectures. I usually create DVDs when the project is finished, then just delete the captures and all else.

This problem still has me baffled. I can't see how a file that was not touched in days gets magically corrupted. I'll still have to check Nelson's test above. I'd be curious to see if a file that gets verified ok gets corrupted some time later.

Oh - I also ran AVI Master command line and it reported the error, "Unexpected Token"

Thanks again.

[edDV]

You might want to ask over at Creative Cow or DMN Premiere Pro forums.

http://forums.creativecow.net/cgi-bin/new_view_posts.cgi?forumid=3
http://www.dmnforums.com/cgi-bin/displaywwugindex.fcgi?forum=adobe_premiere
http://www.tek-tips.com/threadminder.cfm?pid=230

I store my projects on external drives but copy to internal drives for editing or for big projects I swap internal video drives.

These people should be able to advise you on proper setups for editing from a firewire drive.

[Rasaraja]

Thanks again.

I think I'll follow your advice and just get a larger internal Hard Drive, capture there, and use the external for storeage. For now, that seems to be the fastest solution.

I'll continue to research this issue as time allows. It's one of those curious things where it would be interesting to know the cause.

Thanks to all above who responded with help.

Ray K

[Nelson37]

I think your're falling into the trap of using the same app that is corrupting the files to verify them. The file corruption is probably happening when you first close Premiere after the capture.

Just try checking all avi after closing Premiere.

You could nail the problem down by simplifying each Premiere operation into seperate sections, checking each AVI afterward. Simply viewing the directory and checking file size is all you need to do. A zero byte AVI should stand out a bit.

[Rasaraja]

The problem hasn't occured in the last couple of weeks.
I added an internal IDE 400GB Drive to be the capture drive, instead of the external Firewire drive.

Now one thing I discovered when installing the drive that the Win XP registry was not configured for Drives over 137GB.

HKEY_LOCAL_MACHINE -> SYSTEM -> CurrentControlSet -> Services -> atapi -> Parameters -> REG_DWORD EnableBigLba 1

I don't know if this relates in any way to the external firewire drive, but since installing the internal IDE, I haven't seen the problem reoccur. I now use the external drive for backup storeage.