Compile FFmpeg for Windows: compile x264

　　The premise is that the msys2 environment is ready.

• Download and unzip

slightly.

• Generate dll / def

rm *.dll
rm *.def

./configure \
    --prefix=../lib-ffmpeg \
    --host=x86_64-w64-mingw32 \
    --host=mingw64 --enable-shared --disable-thread --disable-avs \
    --extra-ldflags=-Wl,--output-def=libx264.def

# --host=mingw64

make

make install

# 为何叫这个名？
cp libx264-159.dll ../lib-ffmpeg/lib/libx264.dll
cp libx264.def     ../lib-ffmpeg/lib

• Convert to lib

#若要生成64位lib文件则输入如下命令：
lib /machine:X64  /def:../../lib-ffmpeg/libx264.def

#若要生成32位lib文件则输入如下命令：
# lib /machine:i386 /def:../../lib-ffmpeg/libx264.def