In this document I'll try to cover the legal status of this project.


 The most obvious problem is the fact that library uses closed-source 
Win32 DLLs. It can be considered to be 'creating derived work' by
including these DLLs into GPL'ed code. In other words, library may
seem to be 'linked' with these proprietary binaries. That's actually 
a fringe case - the strict definition of 'linking' does not exist yet.
I prefer to think of the DLLs as 'plug-ins', which are separate from
main library and voluntary to use. That's why I distribute binaries and 
sources in different packages - you do not need binaries to compile library
and even to run some test programs. One can someday rewrite DLLs using C/C++
and thus make AVIFile library completely platform independent.

 The DLLs themself are freeware - you can easily get them from lots of
other places. Their licenses typically do not say anything explicitly
about this way of using them. I believe there's nothing wrong in it.