编译FFmpeg是一件痛苦的事情，一般都直接使用。

如果使用这个版本，需要注意ffmpeg的帮助里的一段话：

To create import libraries that work with the /OPT:REF option (which is enabled by default in Release mode), follow these steps:Open the Visual Studio Command Prompt.Alternatively, in a normal command line prompt, call ‘vcvars32.bat’ which sets up the environment variables for the Visual C++ tools (the standard location for this file is something like ‘C:\Program Files (x86_\Microsoft Visual Studio 10.0\VC\bin\vcvars32.bat’).Enter the ‘bin’ directory where the created LIB and DLL files are stored.Generate new import libraries with lib.exe: 	lib /machine:i386 /def:..\lib\foo-version.def  /out:foo.libReplace foo-version and foo with the respective library names.

即根据dll重新生成lib文件。

否则Relesae下就会出问题。

这是VS2010的一个bug，据说VS2012后已经修复。