Ok, so I have been able to build ffmpeg with vhooks on Windows.
As I mentioned in my previous post, vhooks couldn't be built
with Mingw, I needed Cygwin.
Still I couldn't build imlib2.dll,
only null.dll, fish.dll and watermark.dll.
That means I can use only images as watermarks.
Ok now, to build it on Cygwin, you need to have certain cygwin packages.
ust install your Cygwin with all the "Base" packages, plus the following "Devel" ones:
binutils, gcc-core, make, subversion
Do not install binutils-20060709-1 (they are buggy on shared builds); use binutils-20050610-1 instead.
Source for this cygwin info.
Then get the latest svn snapshot from ffmpeg site, that means
the latest ffmpeg source code.
Unzip it, and go inside it using Cygwin prompt.
and type this :
$ ./configure --disable-static --enable-shared --enable-memalign-hack --enable-vhook
Now I got an error that I don't have cmp.exe.
So I searched and found the solution here.
Solution is that you have to install diffutils on cygwin.
Next, I got two errors :
1. rtsp.c:1097: error: 'EPROTONOSUPPORT' undeclared (first use in this function)
Solutions are here.
What I did was replaced EPROTONOSUPPORT in rtsp.c with AVERROR_NOTSUPP
and it worked.
2. version.h:2: error: missing terminating " character.
I looked up version.h, it had a strange ^M character in it, which
I deleted and again
After building vhooks, now I had problems with using the watermark.
You can find the discussion that ensued on Experts-exchange here.