铃音你好,我在milan的主页看到他对于你编译的ffdshow的一些看法 原文如下:
Don't use ffdshow-20050328 By: Milan Cutka on: Wed 06 of Apr, 2005 [08:11 UTC] (6029 reads)
I was notified about new ffdshow build being available. I don't know who created it, but certainly he/she did a poor job.
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The whole package is build in Visual Studio .NET 2003 with Microsoft compiler in Release target. While this isn't bad choice for ffdshow.ax itself and several other libraries included in VS.NET solution, it's inapropriate for building libavcodec and libmplayer.dll. Those two libraries are essential for good performance of ffdshow - libavcodec for decoding/encoding most of video and audio formats and libmplayer for software scaling, many colorspaces conversions and fast mp3 decoder. When those two libraries are build by Microsoft's compiler, all hand optimized code developed to effectively use MMX, 3DNow and SSE extensions is skipped resulting in much worse performance. Use GCC from mingw packages to build them.
And even if you have fast enough computers to use such libraries, ffdshow.ax from that date contained some known bugs introduced during big changes I was making in March which were fixed soon after.
Please be patient, I'll start releasing daily builds soon.
To that unknown builder: I'm sorry for not providing more detailed and up-to-date build instructions, but next time please be so kind and ask me before you'll release ffdshow build to the public. I'll give you instructions how to build ffdshow to get best performance.
大概意思是说仅使用了VC2003编译的话虽不会影响ffdshow.ax和其他某些库文件,但是libavcodec.dll和libmplayer.dll这两个文件会由于VC2003本身编译器跳过使用的MMX,3DNow,SSE代码,而使得解码效率变差。而这两个文件是构成了大部分音视频编解码和MP3解码、后处理的关键。
milan说的有道理吗?下一个版本的ffdshow,铃音准备如何做? |