VS2017下编译QtAV

一、QtAV必需ffmpeg，推荐下面两种方法调用：

1. Put FFmpeg headers and libs into Qt directories

It’s the simplest and best way. Qt include and lib dir are always searched in QtAV. It should work for all platforms, including android, iOS, WinRT and meego etc.

Take Windows for example, Qt is installed in C:\Qt\5.7\msvc2015_64\ . Goto that dir and put ffmpeg headers to include\, libs to lib\

2. Edit .qmake.conf (if use qmake)

Extract ffmpeg to QtAV source dir. add 2 lines in .qmake.conf

INCLUDEPATH += $$PWD/ffmpeg/include
LIBS += -L$$PWD/ffmpeg/lib

二、QtAV没有提供VS工程，要用命令行生成：

打开VS2017的命令提示符窗口，进入QtAV目录，运行

%QTDIR%\bin\qmake -r -tp vc QtAV.pro