Uncompressed AVI over 2GB (1 Viewer)

[MarkHastings]

OK, I painted myself into a corner...I rendered a 3D movie as an uncompressed AVI and the final result is 2.7GB - Obvious the 2GB limit makes the file unreadable.

Since it took over a day to render, I'd hate to re-render with compression...Am I screwed? Is there anything that can knock the file down or at least read it? If not, I'll just have to suck it up and re-render.

 

[ThomasC]

Size shouldn't make the file unreadable. I think you're just using a program that can't handle the size. Virtualdub works fine for me.

 

[MarkHastings]

hmmm, neither Adobe Premiere nor After Effects would read it. Perhaps the file wasn't rendered properly..

 

[Kimmo Jaskari]

Besides, a 2GB limit is an actual 2GB limit. If you have that, you can't write anything larger than that. Thus, if you have a 2.7 GB file, you have no 2GB limit.

Fat32 tops out at 4GB files, I believe. I've run afoul of that with DVD image files on occasion, when I still used fat32 anywhere besides the MP3 player... NTFS has no specific limit, but in theory there has to be some huge limit that isn't practically relevant.

 

[MarkHastings]

Yeah, but this is uncompressed AVI specifically. I've had DV files and MPEG2's, over 2GB, on my system that have worked fine, but I always thought it was the uncompressed AVI format that had trouble over 2GB?

 

[Patrick Sun]

I have a few 27GB AVI files (compressed with HuffyUV) made from LD captures to my NTFS hard drives, so it's not a filesystem issue, but it very well could be a program-specific problem. Which is why you have some DVD programs that will break up the VOB files into 1GB-sized files for DVD creation considerations.

Just for fun, uncompressed, the LD captures were around 65-70GB in size after I used VirtualDub to combine them (2 to 3 sides of LDs).

 

[Bryan X]

I've also got 20-40GB uncompressed AVI files that I can play fine on my PC.

 

[MarkHastings]

Not sure if this is true or not, but I found this:Ok, so my first question is, Is there such thing as a type 1 AVI? and secondly, how do I know if I'm compressing to Type 1???

 

[Marko Berg]

Link to Microsoft discussing Type 1 and Type 2 AVI specifications.

The information is from 2001 (!), I would imagine there is a setting somewhere deep in your software to determine the AVI output that should hopefully be user-selectable unless you're using really ancient rendering software that dates back to pre-Type 2 specifications?

 

[Kimmo Jaskari]

And again, limited in size should mean you can't make a file bigger than 2GB with that specification, so if you have 2.7GB it stands to reason it can't be a type 1.

 

[MarkHastings]

Is this really true? I've had instances in the past where I could render up to 2GB and the files would open fine, but once the file went over the 2GB, it wouldn't play.

The file would actually be larger than 2GB, it just wouldn't open.

 

[Kimmo Jaskari]

Well, I'm just speculating that a limit means that there is an actual limit... but can't actually back that up with facts offhand. Especially as the limit seems to be 4GB in actuality but due to the software it is 2. No, that doesn't make any sense to me either, but that's what it says if you dig around a little on the web.

 

[MarkHastings]

That's what I'm thinking may be the case. The HD is allowing the 4GB limit, but the software is only outputting the Type 1 AVI. I can't analyze the file, so I can't really say if it's actually Type 1, but it's possible.

Assuming it might be the app, I looked online...I can't seem to find much help. I use Poser 6 and they did come out with version 7 not too long ago, so maybe 6 is too old for this kind of render? But again, I can't seem to find any documentation anywhere about this and I'd hate to upgrade and find out it doesn't solve the issue.

No biggie though, I'll just have to re-render and see what happens...

 

[Kimmo Jaskari]

Actually it's not just the hardware limit that is 4GB (and that is only on fat32, not NTFS) but the limit in avi type 1 is 4GB but also 2GB. Weird and incomprehensible, but then again Microsoft wrote the standard.

 

[Ken Chan]

Unless there's a bug in the program/library, blindly spewing out chunks (that's a technical term) even though it has gone past the limit. In the old days, maybe the filesystem would have put a hard stop to it. If AVI readers can't read the file because it's invalid, it could be a very simple error, and the data is actually all in there. But good luck figuring that out.

 

[MarkHastings]

Ok, so I downloaded VirtualDub and as I started to open the file, it said:
Reconstructing missing index block...

Then when it finished, it said:
[!] AVI: Index not found or damaged -- reconstructing via file scan.

[!] AVI: Invalid chunk detected at 2826260456. Enabling aggressive recovery mode.

but then the program played the file, so I saved it as a new AVI file. The new file is 2.07GB and it plays in WMP, but when it gets to the end, there appears to be some damage to the movie. In the last few seconds, there's some pixelization in the center of the movie.

As to why the file is smaller...the file is definitely uncompressed, but I believe the original file had an alpha channel whereas this does not. That could be where the 700MB differential is coming from, but at this point I'm lost.This is sounding like what may have happened. The program was spitting out a Type 1 AVI and since the file system can handle up to 4GB, it didn't stop the app from going over 2GB - It seems that since the artifacting happened in the last few seconds of the file, that may be at the point that the 2GB was reached, thus corrupting the file (or preventing the 3D app from writing the last block of the file?). VirtualDub did a good job of recovering it, but the damage appears to have already been done. I'll just have to re-render the file either with compression or in chunks next time.

Thanks to everyone for your help.

 

[Rob Gardiner]

Mark,

Here http://www.videohelp.com/tools?tool=...File_Converter is a program that claims to be able to convert from Type 1 to Type 2 with no quality loss. Specifically mentioned is a problem opening files in Virtual Dub. I hope this helps.