Factors that can limit an AVI's size may include the filesystem, and the type of AVI file itself.
With the latest implementations of the FAT filesystem i.e. DOS, Windows 3.x, Windows 95 (pre-SR2) (no longer commonly used), maximum file size is 2GB.
With the latest implementations of the FAT32 filesystem i.e. Win95 SR2, Win98, Win2k, WinXp maximum file size is 4GB.
Here are your commonly associated 2GB/4GB filesize limitations, however, implementations of AVI may also be further limited by things like:
AVI 1.0
Microsoft's Video for windows has some hardwired limitations that impose a maximum video filesize of 1-2GB depending on the version of the RIFF parser code in the MCIAVI driver.
Surprisingly enough, much video software was written to these standards and this is where much of today's incompatibility stems from.
The AVI file header is 32-bits in length. As a result there is a 4GB limitation in its file size.
With the latest implementations of NTFS maximum filesize is limited only by the volume size which is currently rated to be 2 Terabytes+ is maximum size.
Even with NTFS as a filesystem, which most of us are now running, you may have software applications, drivers, and plugins that only will function up to the 4GB limitation of a native AVI or worse yet, only up to the 1-2GB limited sizes imposed by early versions of AVI implementations (Video for Windows).
OpenDML file format extensions (AVI-compatible). These extensions were written to over come AVI filesizes limitations of 1GB / 2GB / 4GB and to incorporate specialized AVI information into the AVI file's chunks.
Some AVI chunk size / extension header progressions: (chunks, or data structures, are the portions of the AVI file that software drivers and applications deal with. these are the units that all of this limit stuff is about. Extension headers are the part of the AVI file that has information flagged if there is something non-standard about the AVI file. For example, it if is larger that 1GB in size.)
Limited to 1GB MCIAVI
Extensions for >1GB AVIX
Entensions for >4GB AVI_INDEX as well as other meta index structures
AVI 2.0 (OpenDML 1.02)
The most significant change with AVI 2.0 (now implemented in MS' Direct Show filters) is the ability to concatenate multiple AVI chunks through the use of 64-bit data types.
Theoretically, this would allow 18 Billion GB's. While not technically unlimited, it certainly far exceeds what most need for their DV projects.
Additionally, AVI 2.0 is superior in that it uses a meta index file structure at the beginning of the file as opposed to AVI 1.0, which uses an index at the end of a file, therefore AVI 2.0 has significant "Seeking" advantages- a must for large AVI files
Most professional video software companies have adopted the use of AVI 2.0 format and OpenDML 1.02 file format extensions.
But what these standards really means is that there is a set of guidelines available if companies choose to use them. It may not always be a good idea or even a cost effective choice to fully utilize all extensions in OpenDML. i.e. StormEdit.
Sources for this thread came from documents like:
http://www.the-labs.com/Video/odmlff2-avidef.pdf
http://www.microsoft.com/windowsxp/home/using/productdoc/en/default.asp?url=/WINDOWSXP/home/using/productdoc/en/choosing_between_NTFS_FAT_and_FAT32.asp
http://www.microsoft.com/whdc/archive/dvavi.mspx
http://www.jmcgowan.com/aviauthor.html#DVAVI1
http://www.thozie.de/avimaster/avi_faq.htm
Lots of this information was copied from a thread in canopus forums, thanks to Chas.
Some of this is repeated, but it also may add information for peoples interest.
In the beginning, there was Video for Windows (VfW) and the data-wrapping file format AVI.
Video for Windows AVIs are often referred to as "AVI 1.0" AVI files.
Video for Windows AVIs were originally limited to 1 GB maximum size, but the size was later extended to 2 GB.
FAT (FAT16) was the filesystem used at the time.
FAT has 2GB maximum file size, and a 2GB maximum volume size (in NT you could format a FAT volume from 2GB up to 4GB with 64KB clusters, which can be problematic).
Circa Windows 95, ActiveMovie was introduced. ActiveMovie still used AVI. ActiveMovie later morphed into DirectShow. DirectShow is often referred to as "AVI 2.0"
At the same time, FAT32 was introduced.
FAT32 has a 4GB maximum file size, and a 127GB (Win9x) or 2TB (WinME, practical limit due to partition table) maximum volume size.
Meanwhile, there's NTFS, used by various versions in NT, 2000, and XP.
NTFS has a current practical limit file size and volume size of about 32TB.
Matrox and some others proposed an extension to AVI 1.0 called OpenDML, which was later implemented in AVI 2.0. This extension allowed AVIs to be larger than 2GB.
Canopus had its own extension of AVI 1.0, used in its applications, called Reference AVIs. This allowed a single AVI up to 4 GB, and multiple "reference" data files, allowing the total content to be over 4 GB.
So, a particular AVI file can be one of four types - Video for Windows aka "AVI 1.0" or DirectShow aka "AVI 2.0"
It's worth noting here that it is possible to create a "partially backward-compatible AVI 2.0" file, but the ability for VfW to access the AVI content is limited to the first 1, 2 or 4GB of the AVI, depending on the method the program uses to access it.
And the filesystem the AVI is stored on can be one of three types - FAT (FAT16), FAT32, or NTFS
This gives us this for maximum AVI sizes by AVI type and filesystem.
Copied in it's entirety from The Grass Valley (Canopus) forum, written by Brandon.
