AVI 4GB Limit Explained

Be careful when dealing with large files! The Windows 95/8 file system cannot handle AVI files larger than 4 gigabytes! There has been much confusion regarding this issue. In short, the old Windows File Allocation Tables (FAT16) cannot store more than 2 gigabytes per file. Windows 98's FAT32 allows a 4 gigabyte storage capacity per single file. So where does the 1 and 2 gig storage limit come in? Most AVI parsers use something called signed arithmetic. This forces a storage limit of 2 gigabytes for .avi files on Windows 98. But the multimedia system in Windows 95 cannot cope with RIFF files (such as .avi files) bigger than 1 gigabyte! And this is why people will say there is either a 1, 2 or 4 gigabyte limit on single file storage. This is why DeCSS, DOD Power Ripper, Vob Merge, Peck Power Join and all other programs like this are incapable of storing more than 4 gigabytes on most peoples computer systems! I think this is the chief reason for so many unexplained error messages when using these programs too!

There is a partial way around this that is used extensively by Virtual Dub that is similar to OpenDML. These settings can be used to create very large .avi files by grouping smaller files together so they are forced to play in sequence. This solution means that the finished files can only be played with Windows Media Player or other programs that support OpenDML type files. For more details on this consult the VirtualDub help files.