Symbols not found in architecture x86_64

[Trav]

ERROR OUTPUT IN APPLICATION:
:-1: error: symbol(s) not found for architecture x86_64:-
1: error: linker command failed with exit code 1 (use -v to see invocation)

Im desperately trying to get my code running this is an integration with openCV , could someone please help explain these errors to me or why my code doesn't work? thanks in advance; I'm using opencv 3.1.0

#include "mainwindow.h"
#include <QApplication>
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <opencv2/videoio/videoio.hpp>
#include<opencv2/objdetect/objdetect.hpp>
#include<opencv2/imgproc/imgproc.hpp>
#include<vector>
#include<string>

#include <iostream>
#include<stdio.h>

using namespace cv;
using namespace std;

CascadeClassifier face_cascade;



void detectFaces(Mat frame) {

  vector<Rect> faces;
  Mat frame_gray;
  cvtColor(frame, frame_gray, COLOR_BGR2GRAY);  // Convert to gray scale
  equalizeHist(frame_gray, frame_gray);   	// Equalize histogram

  // Detect faces
  face_cascade.detectMultiScale(frame_gray, faces, 1.1, 3,
                0|CASCADE_SCALE_IMAGE, Size(30, 30));

  // Iterate over all of the faces
  for( size_t i = 0; i < faces.size(); i++ ) {

    // Find center of faces
    Point center(faces[i].x + faces[i].width/2, faces[i].y + faces[i].height/2);

    // Draw ellipse around face
    ellipse(frame, center, Size(faces[i].width/2, faces[i].height/2),
        0, 0, 360, Scalar( 255, 0, 255 ), 4, 8, 0 );
  }

  imshow( "window",frame);  // Display frame
}




int main(int argc, char *argv[]){
    QApplication a(argc, argv);
    MainWindow w;
 // cam code
try{


        VideoCapture cap(0);        // Open default camera
          Mat frame;

          // Load preconstructed classifier
          face_cascade.load("haarcascade_frontalface_alt.xml");

          while(cap.read(frame)) {
            detectFaces(frame);       // Call function to detect faces
            if( waitKey(30) >= 0)     // Pause key
                break;
          }
}catch(Exception ex){
std::cout << "Unable to initiate camera" << std::endl;
    }
    //end cam code



    w.show();
return a.exec();
}

[SGaist]

Hi,

What symbols are missing ?

Are you sure you have linked to all the necessary libs ?

Are they of the correct architecture ?

[Trav]

This is my PRO file below, thanks for your reply; Im not quite sure i really don't understand whats going on, I have been able to get the live camera feed from my code but when implementing the face detection in openCV I am getting this issue .pro file as follows:

#-------------------------------------------------
#
# Project created by QtCreator 2016-05-25T01:38:34
#
#-------------------------------------------------

QT       += core gui

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

TARGET = Origin
TEMPLATE = app


SOURCES += main.cpp\
        mainwindow.cpp


LIBS += \
-L/usr/local/lib \
-lopencv_core \
-lopencv_highgui \
-lopencv_videoio \
-lopencv_objdetect


INCLUDEPATH += \
    /usr/local/include

HEADERS  += mainwindow.h

FORMS    += mainwindow.ui

[SGaist]

Looks fine but again: what symbols are missing ?

[Trav]

Symbols in what context? Im fairly new to Qt apologies for being a little slow in advance but this is my compile output:
If you are asking a specific question ill gladly get the info needed if you could just show me where i can find this, thanks again for your help

16:32:52: Running steps for project Origin...
16:32:52: Configuration unchanged, skipping qmake step.
16:32:52: Starting: "/usr/bin/make" 
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang++ -c -pipe -stdlib=libc++ -g -std=gnu++11 -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk -mmacosx-version-min=10.7 -Wall -W -fPIC -DQT_QML_DEBUG -DQT_WIDGETS_LIB -DQT_GUI_LIB -DQT_CORE_LIB -I../Origin -I. -I/usr/local/include -I../../Qt/5.6/clang_64/lib/QtWidgets.framework/Headers -I../../Qt/5.6/clang_64/lib/QtGui.framework/Headers -I../../Qt/5.6/clang_64/lib/QtCore.framework/Headers -I. -I/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk/System/Library/Frameworks/OpenGL.framework/Headers -I/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk/System/Library/Frameworks/AGL.framework/Headers -I. -I../../Qt/5.6/clang_64/mkspecs/macx-clang -F/Users/travishaycock/Qt/5.6/clang_64/lib -o main.o ../Origin/main.cpp
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang++ -headerpad_max_install_names -stdlib=libc++ -Wl,-syslibroot,/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk -mmacosx-version-min=10.7 -Wl,-rpath,/Users/travishaycock/Qt/5.6/clang_64/lib -o Origin.app/Contents/MacOS/Origin main.o mainwindow.o moc_mainwindow.o   -F/Users/travishaycock/Qt/5.6/clang_64/lib -L/usr/local/lib -lopencv_core -lopencv_highgui -lopencv_videoio -lopencv_objdetect -framework QtWidgets -framework QtGui -framework QtCore -framework OpenGL -framework AGL 
Undefined symbols for architecture x86_64:
  "cv::equalizeHist(cv::_InputArray const&, cv::_OutputArray const&)", referenced from:
      detectFaces(cv::Mat) in main.o
  "cv::ellipse(cv::_InputOutputArray const&, cv::Point_<int>, cv::Size_<int>, double, double, double, cv::Scalar_<double> const&, int, int, int)", referenced from:
      detectFaces(cv::Mat) in main.o
  "cv::cvtColor(cv::_InputArray const&, cv::_OutputArray const&, int, int)", referenced from:
      detectFaces(cv::Mat) in main.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [Origin.app/Contents/MacOS/Origin] Error 1
16:32:55: The process "/usr/bin/make" exited with code 2.
Error while building/deploying project Origin (kit: Desktop Qt 5.6.0 clang 64bit)
When executing step "Make"
16:32:55: Elapsed time: 00:03.

[SGaist]

That's nothing Qt specific, it's standard C++.

You are not linking to the OpenCV module that provides these symbols. For example equalizeHist comes from imgproc

[Trav]

This post is deleted!