FFMpeg (trunk revision 21487)
Build instructions for Win32:

Requirement:
1) MinGW
   http://mingw.org/
2) MSYS
   http://www.mingw.org/wiki/msys
3) MSYS DTK
4) NASM/YASM

How to build from sources using MinGW+MSYS:
1) Download and compile zlib sources (zlib-1.2.3.tar.gz)
   http://zlib.net/

$ tar zxfv zlib-1.2.3.tar.gz
$ cd zlib-1.2.3
$ ./configure --prefix=/ming
$ make
$ make install

2) Download and compile bzip2 sources (bzip2-1.0.5.tar.gz)
   http://www.bzip.org/

$ tar zxfv bzip2-1.0.5.tar.gz
$ cd bzip-1.0.5.tar.gz
$ patch -p0 ../bzip2-1.0.5-extensions.diff
$ make
$ make install PREFIX=/mingw

3) Download and compile lame (lame-3.97.tar.gz)
   http://lame.sourceforge.net/

$ tar zxfv lame-3.97.tar.gz
$ cd lame-3.97
$ patch -p0 < ../lame.diff
$ ./configure --prefix=/mingw --disable-shared --enable-static --disable-frontend --enable-nasm
$ make
$ make install

4) Obtain sources of FFmpeg
   http://ffmpeg.org/

$ svn co svn://svn.ffmpeg.org/ffmpeg/trunk ffmpeg -r 21487
$ cd ffmpeg

5) Patch for enabling audio/video capture. 
   That is actual for 2.5.x versions

$ patch -p0 < ../ffmpeg-grabdc-wavein.diff

6) Configure and build FFmpeg

$ ./configure \
--extra-libs=-lgdi32 --extra-libs=-lwinmm --extra-cflags=-fno-common --disable-shared --enable-static \
--disable-doc --disable-ffplay --disable-ffserver  \
--enable-memalign-hack --enable-bzlib \
--enable-libmp3lame --disable-network --enable-swscale --enable-avisynth
$ make


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