After Effects 2GB AVI Limit
 

I seem to have hit a brick wall.
Using;
NEO Scene (Latest version)
After Effects CS3
Windows Vista 64-bit

I've managed to get After Effects to create a CFHD AVI file bigger than 2GB - just using the 'Video for Windows' output as with NEO Scene the Cineform export is not available.

However, I cannot get After Effects to load the file back in successfully - it works fine in Vegas 8 and VirtualDub it seems. I just get a black screen in After Effects (In fact I can't see all the file properties either)

The GSpot program says it's fine too. What can I do to get it into After Effects?

(I've tried uninstalling and reinstalling several times including deleting any old files left behind).

Many thanks

Back in the "old days" (Pre-1996), there was a 2GB file size limit for AVI files. This was a function of the basic file structure:

RIFF:
4 bytes : RIFF_ID
4 bytes : size <- signed value!
4 bytes : RIFF_type
size-4 bytes: data

In order to break this limit, Matrox introduced the Open-DML extensions to the AVI file format which were adopted on 06/28/1996. Open-DML is also referred to as "AVI 2.0". The most important extension is that several RIFF items of 2 GB each could be appended, which effectively removed the 2 GB limit.

Most programs since then will generate and recognize AVI 2.0 files. There should be no practical file size limit when creating an AVI 2.0 (Open DML) file on a drive which has been formatted using the NTFS file system. (There is still a 4 GB limit on drives using the FAT32 file system, but that is a limitation of the file system, not the AVI specs.)

Cineform NEO Scene is a VFW-compatible codec, so there is no reason that After Effects shouldn't be able to create and load Cineform AVI files of any size. I'm not on a machine with After Effects at the moment, but I don't believe that there is any sort of Open-DML switch in the render engine. Certainly something to check though.

Basicallly, all I've done here is tell you why this problem can't have happened, but it clearly has happened to you. I'd suspect that this is probably an After Effects issue. I'll look around and see if I can find anyone else with your specific problem. Have you looked in the Adobe AE forums?

Thanks for the reply - I understand the principles, which is why I've hit a brick wall. Programs other than AE read it fine - I created the file with AE too, which means it's creating the right kind (Open DML) of file.

But when you read it in it must be using an incorrect importer or something.

I have a feeling it's the Cineform Importer for AE - or more precisely that AE is using the wrong importer...but I don't know how to check what AE is using, the standard VFW one or the Cineform one.

I've looked all over for answers and most posts are rather old and are because people were using Type 1 files.

Further thoughts?

Since you have Virtual Dub, have you tried simply remuxing the file by opening the file, setting Virtual Dub to do a "direct stream copy" and saving the file. It's worth a try.

Also, I ran across this which suggests that a Microsoft component has a problem reading the index of certain Open-DML files.

AVI-Mux GUI - about Open-DML

Doh! Don't know why I didn't think of that - ReMuxing through VirtualDub fixes the AVI file so AE can read it.

So I wonder whether it is the output side of AE with Cineform that's the issue.

Thanks for your help and suggestions - I'd still like to know if it can be fixed properly though, I seem to recall David N. saying that NEO Scene's exporter is limited, maybe this is part of it.

Many thanks

Simon