opencv raspicam configuration C++ Example

Question

I need any help with this error

pi@raspberrypi ~/opencam_test $ sudo g++ simpletest_raspicam_cv.cpp -o  simpletest_raspicam_cv -I/usr/local/include/ -lraspicam -lraspicam_cv -lmmal -lmmal_core -lmmal_util -lopencv_core -lopencv_highgui 
/usr/bin/ld: /tmp/cc2tVouL.o: undefined reference to symbol 'cv::imwrite(cv::String const&, cv::_InputArray const&, std::vector<int, std::allocator<int> > const&)'
//usr/local/lib/libopencv_imgcodecs.so.3.1: error adding symbols: DSO missing from command line
collect2: ld returned 1 exit status

I try an example for be sure that the raspicam is correctly configured with opencv-3.1.0 this is the site which i follow http://www.uco.es/investiga/grupos/ava/node/40

and this is my src code which i want to compile

#include <ctime>
#include <iostream>
#include <raspicam/raspicam_cv.h>

using namespace std; 

int main ( int argc,char **argv ) {

    time_t timer_begin,timer_end;
    raspicam::RaspiCam_Cv Camera;
    cv::Mat image;
    int nCount=100;
    //set camera params
    Camera.set( CV_CAP_PROP_FORMAT, CV_8UC1 );
    //Open camera
    cout<<"Opening Camera..."<<endl;
    if (!Camera.open()) {cerr<<"Error opening the camera"<<endl;return -1;}
    //Start capture
    cout<<"Capturing "<<nCount<<" frames ...."<<endl;
    time ( &timer_begin );
    for ( int i=0; i<nCount; i++ ) {
        Camera.grab();
        Camera.retrieve ( image);
        if ( i%5==0 )  cout<<"\r captured "<<i<<" images"<<std::flush;
    }
    cout<<"Stop camera..."<<endl;
    Camera.release();
    //show time statistics
    time ( &timer_end ); /* get current time; same as: timer = time(NULL)  */
    double secondsElapsed = difftime ( timer_end,timer_begin );
    cout<< secondsElapsed<<" seconds for "<< nCount<<"  frames : FPS = "<<  ( float ) ( ( float ) ( nCount ) /secondsElapsed ) <<endl;
    //save image 
    cv::imwrite("raspicam_cv_image.jpg",image);
    cout<<"Image saved at raspicam_cv_image.jpg"<<endl;
}

Answer 1

try something like this...

g++ `pkg-config opencv --cflags` program_name.cpp -o  program_name `pkg-config opencv --libs` -I/usr/local/include/ -lraspicam -lraspicam_cv

Answer 2

I could not reproduce your problem but I was able to compile and run your code. The output was:

Opening Camera...Capturing 100 frames .... captured 95 imagesStop camera... 3 seconds for 100 frames : FPS = 33.3333 Image saved at raspicam_cv_image.jpg

I did it with make and CMake files. It leads me to believe the problem is that you have a missing/redundant library(s) in the command line, namely:

//usr/local/lib/libopencv_imgcodecs.so.3.1: error adding symbols: DSO missing from command line

CMake and make are programs that perform all that command like compile information for you. I can help you if you have any problems using this method.