undefined reference to `x264_encoder_open_125'

Question

While installing ffmpeg on Ubuntu 12.04

I am getting following error

libavcodec/libavcodec.a(libx264.o): In function `X264_init':
/root/ffmpeg/libavcodec/libx264.c:492: undefined reference to `x264_encoder_open_125'
collect2: ld returned 1 exit status
make: *** [ffmpeg_g] Error 1

I am following the instructions given at http://ffmpeg.org/trac/ffmpeg/wiki/UbuntuCompilationGuide

Do anyone have idea about this error?

Answer 1

This is a typical problem for people who already have x264 installed through the package management system. You can solve this in at least 2 ways:

1. Uninstall the already existing x264 from your system, through the package management system:

   # apt-get remove x264
   

   and compile your new x264 from source

2. Don't uninstall the x264 package, but compile your new x264 and then compile your ffmpeg, telling it to use that newly compiled x264 library, by specifying that directory where your compiled x264 library is, using the mentioned LD_LIBRARY_PATH environment variable:

   LD_LIBRARY_PATH=/path/to/my/compiled/x264/library ./configure --enable-libx264 ...
   

More info can be found on these links:

• problem with --enable-libx264 option in ffmpeg
• Compiling FFmpeg