caffe編譯出現

/usr/local/lib/libopencv_highgui.so: undefined reference to `[email protected]_4.0'

或者

/lib/libcaffe.so.1.0.0-rc5: undefined symbol: ZN2cv8imencodeERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEERKNS

原因：

用ldd命令列出libcaffe.so.1.0.0-rc5依賴的動態庫，發現了問題，如下圖：

~/eclipseworkspace/caffe-master-alexnet-triplet (copy)/build/lib$ ldd libcaffe.so.1.0.0 |grep opencv
    libopencv_core.so.2.4 => /usr/local/MATLAB/R2016b/bin/glnxa64/libopencv_core.so.2.4 (0x00007f5e6e03f000)
    libopencv_highgui.so.2.4 => /usr/local/MATLAB/R2016b/bin/glnxa64/libopencv_highgui.so.2.4 (0x00007f5e6de1a000)
    libopencv_imgproc.so.2.4 => /usr/local/MATLAB/R2016b/bin/glnxa64/libopencv_imgproc.so.2.4 (0x00007f5e6d983000)

原來我使用的matlab中自帶了opencv動態庫，而且它在LD_LIBRARY_PATH的優先順序更高，所以libcaffe.so.1.0.0-rc5在執行時使用了matlab下的opencv庫，而不是我apt-get安裝的opencv庫。

將環境變數修改為opencv lib所在的路徑。

sudo geidt ~/.bashrc