ffmpeg / libav在Windows中鏈接問題

Question

我已經從Linux到Windows（mingw32）交叉編譯了ffmpeg和libav。 所以，我已經有了我的.a文件，准備在我的MSVC2010項目中用於鏈接。 問題是我得到鏈接錯誤，我不明白為什么：

1>RTSPCapture.obj : error LNK2019: unresolved external symbol _avformat_free_context referenced in function "public: int __thiscall Imagsa::RTSPCapture::dumpSync(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &,class std::basic_stringstream<char,struct std::char_traits<char>,class std::allocator<char> > &,double *,class std::vector<class Imagsa::MjpegFrame,class std::allocator<class Imagsa::MjpegFrame> > &)" (?dumpSync@RTSPCapture@Imagsa@@QAEHABV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@0AAV?$basic_stringstream@DU?$char_traits@D@std@@V?$allocator@D@2@@4@PANAAV?$vector@VMjpegFrame@Imagsa@@V?$allocator@VMjpegFrame@Imagsa@@@std@@@4@@Z)
1>RTSPCapture.obj : error LNK2019: unresolved external symbol _avio_close referenced in function "public: int __thiscall Imagsa::RTSPCapture::dumpSync(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &,class std::basic_stringstream<char,struct std::char_traits<char>,class std::allocator<char> > &,double *,class std::vector<class Imagsa::MjpegFrame,class std::allocator<class Imagsa::MjpegFrame> > &)" (?dumpSync@RTSPCapture@Imagsa@@QAEHABV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@0AAV?$basic_stringstream@DU?$char_traits@D@std@@V?$allocator@D@2@@4@PANAAV?$vector@VMjpegFrame@Imagsa@@V?$allocator@VMjpegFrame@Imagsa@@@std@@@4@@Z)
1>RTSPCapture.obj : error LNK2019: unresolved external symbol _avcodec_close referenced in function "public: int __thiscall Imagsa::RTSPCapture::dumpSync(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &,class std::basic_stringstream<char,struct std::char_traits<char>,class std::allocator<char> > &,double *,class std::vector<class Imagsa::MjpegFrame,class std::allocator<class Imagsa::MjpegFrame> > &)" (?dumpSync@RTSPCapture@Imagsa@@QAEHABV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@0AAV?$basic_stringstream@DU?$char_traits@D@std@@V?$allocator@D@2@@4@PANAAV?$vector@VMjpegFrame@Imagsa@@V?$allocator@VMjpegFrame@Imagsa@@@std@@@4@@Z)

有誰知道會發生什么？

Answer 1

包含libav *頭時，必須使用C樣式名稱修改。

extern "C"
{
#include <libavcodec/avcodec.h>
#include <libavcodec/avcodec.h>
...
}

Answer 2

最后我意識到Mingw編譯的libs無法從VS2010本機應用程序鏈接。