架构的未定义符号x86_64: cv::CascadeClassifier::CascadeClassifier()

Question

我在OSX上的Qt 5.2中使用openCV 2.4.6.1。一切都很好，但是当我尝试使用cv:: cascadecclassifier时，出现链接错误，表明该符号未为体系结构x86_64定义。有什么解决办法吗?谢谢。

TEMPLATE = app
TARGET = camera
QT += multimedia multimediawidgets
INCLUDEPATH += /usr/local/Cellar/opencv/2.4.6.1/include 
LIBS += -L/usr/local/Cellar/opencv/2.4.6.1/lib 
     -lopencv_core 
     -lopencv_imgproc 
     -lopencv_features2d 
     -lopencv_highgui
HEADERS = 
    camera.h 
    imagesettings.h 
    videosettings.h 

SOURCES = 
    main.cpp 
    camera.cpp 
    imagesettings.cpp 
    videosettings.cpp 
FORMS += 
    camera.ui 
    videosettings.ui 
    imagesettings.ui
target.path = $$[QT_INSTALL_EXAMPLES]/multimediawidgets/camera
INSTALLS += target
QT+=widgets

Answer 1

您需要在项目文件中扩展LIBS变量，因为cv:CascadeClassifier可以在该库中找到:

LIBS += -L/usr/local/Cellar/opencv/2.4.6.1/lib 
    -lopencv_core 
    -lopencv_imgproc 
    -lopencv_features2d 
    -lopencv_highgui 
    -lopencv_objdetect # This is the addition

Answer 2

这为我修复了它:

在项目的Build Settings选项卡中，向下滚动到"Apple LLVM Compiler 4.1 - Language"
• 将"c++语言方言"设置为"c++11 [-std=c++11]"
• 将"c++标准库"设置为"libc++(支持c++ 11的LLVM标准c++库)"

来自:

http://answers.opencv.org/question/4655/link-error-for-only-cascadeclassifier-under-243/