Introduction

FFMPEG is a set of libraries (libavcodec, libavformat, libavutil) for reading and writing audio/video file formats and decompressing and compressing their contents. In other words, FFMPEG is a program that can play audio and video files, do image processing on them, and create new files in many different formats. If you'd like to learn more about it, you can look at their webpage: http://ffmpeg.sourceforge.net/

My Patch

I was working on a project for connecting to an Axis 213 camera to read mpeg4 video in an RTSP stream. I was using the FFMPEG libraries to do this, but unfortunately the networking code only worked on Unix and BEOS operating systems and I need a cross platform solution. I submitted my patch to the FFMPEG people, and altho some of the people wanted to accept my patch, some of the people higher up in the project did not want to accept my patches, therefore I'm posting them here for anyone who needs networking support on Windows with FFMPEG. I really don't understand why Windows is such a big deal to them. I mean if people enjoy bobbing for apples in a toilet full of poop, I say let them.

NOTE: I am not a part of the FFMPEG team. I just simply changed a few lines of their code to make it compile and run on Windows.

CHANGES IN LATEST PATCH ARE:

• Change configure to allow network under MingW
• Clean up BeOS headers and include MingW
• Get rid of calls to the function read()/write() and change to cross-platform recv()/send()
• Raise the size of the socket buffer
• Fix a bug that allows ffmpeg to bind to more ports so that multiple instances of ffplay can run
• Probably more stuff I'm forgetting

Note: The ffmpeg team has actually fixed most, if not everything that these patches take care of, so they are probably useless now. I need to check the mutiple rtsp streams problem and the udp buffer size when I get a chance.

Download

The 2006-11-09 patch works on Subversion code as of November 09, 2006

ffmpeg_kohn_rtsp_mingw-2006-11-09.patch
ffmpeg_kohn_rtsp_mingw-2006-11-08.patch
ffmpeg_kohn_rtsp_mingw-2006-11-06.patch
ffmpeg_kohn_rtsp_mingw-2006-06-23.patch
ffmpeg_kohn_rtsp_mingw-2006-04-03.patch

Install

To install this, download the latest svn version as mentioned on their page http://ffmpeg.sourceforge.net/download.php and apply the patch by typing:

svn checkout svn://svn.mplayerhq.hu/ffmpeg/trunk ffmpeg
cat ffmpeg_kohn_2006-11-08.patch | patch -p0

Then run the configure script within MSYS and type: make

NOTE: This will not make FFMPEG compile with Microsoft Visual C++. FFMPEG written to compile with gcc so it requires the MINGW gcc compiler.

To build with a cross compiler on Gentoo Linux I configure with

./configure --enable-mingw32 --cross-prefix=i386-mingw32msvc- --enable-memalign-hack --arch=x86 --cpu=pentium4

More recently, this seems to be the way to do it: ./configure --target-os=mingw32 --cross-compile --arch=x86 --cpu=pentium4 --cross-prefix=mingw32- --extra-cflags=-D__STDC_LIMIT_MACROS