在 Raspberry Pi 2 上编译 OpenCV

Question

I am compiling OpenCV on a Raspberry 2 and I am jammed on this step,

[ 18%] Building CXX object modules/highgui/CMakeFiles/opencv_highgui.dir/src/cap_ffmpeg.cpp.o

with returned a lot of error, I take only 2 of the begining, other of them look the same but different on { CODEC_ID_H264, MKTAG('h', '2', '6', '4') },

In file included from /home/pi/opencv/modules/highgui/src/cap_ffmpeg_impl.hpp:60:0,
                 from /home/pi/opencv/modules/highgui/src/cap_ffmpeg.cpp:45:
/home/pi/opencv/modules/highgui/src/ffmpeg_codecs.hpp:104:7: error: 'CODEC_ID_H264' was not     declared in this scope
     { CODEC_ID_H264, MKTAG('H', '2', '6', '4') },
       ^
/home/pi/opencv/modules/highgui/src/ffmpeg_codecs.hpp:105:7: error: 'CODEC_ID_H264' was not     declared in this scope
     { CODEC_ID_H264, MKTAG('h', '2', '6', '4') },
       ^

and the final part is about

/home/pi/opencv/modules/highgui/src/cap_ffmpeg_impl.hpp: In member function 'double     CvCapture_FFMPEG::get_fps()':
/home/pi/opencv/modules/highgui/src/cap_ffmpeg_impl.hpp:821:49: error: 'AVStream' has no member named 'r_frame_rate'
     double fps = r2d(ic->streams[video_stream]->r_frame_rate);
                                             ^
In file included from /home/pi/opencv/modules/highgui/src/cap_ffmpeg.cpp:45:0:
/home/pi/opencv/modules/highgui/src/cap_ffmpeg_impl.hpp: In function 'int         icv_av_write_frame_FFMPEG(AVFormatContext*, AVStream*, uint8_t*, uint32_t, AVFrame*)':
/home/pi/opencv/modules/highgui/src/cap_ffmpeg_impl.hpp:1237:72: error: 'avcodec_encode_video'     was not declared in this scope
         out_size = avcodec_encode_video(c, outbuf, outbuf_size, picture);
                                                                    ^
modules/highgui/CMakeFiles/opencv_highgui.dir/build.make:215: recipe for target     'modules/highgui/CMakeFiles/opencv_highgui.dir/src/cap_ffmpeg.cpp.o' failed
make[2]: ** [modules/highgui/CMakeFiles/opencv_highgui.dir/src/cap_ffmpeg.cpp.o] Error 1
CMakeFiles/Makefile2:1823: recipe for target 'modules/highgui/CMakeFiles/opencv_highgui.dir/all'     failed
make[1]: *** [modules/highgui/CMakeFiles/opencv_highgui.dir/all] Error 2
Makefile:137: recipe for target 'all' failed

Please help me for this while I get stucked on it for a long time after tried few times, thank you

Answer 1

This error is probably due to the fact you are using the ffmpeg from the repositories. When building OpenCV from source it is strongly recommended to build the respective ffmpeg version too. Remove any installation of ffmpeg and x264 from your Pi and then do a build.

Check this guide here for more information.