Build Error with CalcOpticalFlowFarneback Function -> OpenCV -> C Language - Eclipse -> MacOSX

asked 2013-01-05 11:48:08 -0500

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hi, i have to do a program using C Language and OpenCV Libreries for a project, I followed the guide for the installation for MACOSX on this site: OpenCV Installation

I used Mac Port for the Istallation.

I use Eclipse to program, Now when i try to compile this program, i get a Build Error and i think that it depends to CalcOpticalFlowFarneback() Function.

This is the code:

 #include <stdio.h>
  #include <cv.h>
  #include <highgui.h>
  #include <math.h>
  #include <time.h>

int main(){

    CvCapture* webcam = cvCreateCameraCapture(0);
    char scelta;



    double pyr_scale=0.5; 
    int levels=1;
    int winsize=3; 
    int iterations=10;
    int poly_n=5; 
    double poly_sigma=1.1;
    int flags=0;


    if (!webcam){
    /* Exit with an error */
        puts("Attenzione! si è verificato un Errore in Fase di Attivazione della WebCam. Preghiamo di Riprovare!");
        return -1;

    while (1) {

        prev = cvQueryFrame(webcam);//primi 8-bit single-channel immagine in ingresso
        next = cvQueryFrame(webcam);// immagine secondo ingresso della stessa dimensione e lo stesso tipo prev.

        CvSize isize = cvSize(80,80);
        IplImage *flow = cvCreateImage(isize, IPL_DEPTH_32F, 1); //immagine computerizzata che ha le stesse dimensioni e tipo CV_32FC2 prev
        if ((prev) && (next)) {


            if((char)scelta == 27){




    cvDestroyWindow("VIDEO SORVEGLIANZA");

    return 0;

and this is the error Log:

>     Undefined symbols for architecture x86_64: "_cvCalcOpticalFlowFarneback",
> referenced from:_main in main.o
>     ld: symbol(s) not found for architecture x86_64
>     collect2: ld returned 1 exit status
>     make: *** [cattura_foto] Error 1

And I want to specify that if i remove the cvCalcOpticalFlowFarneback Function i do not have any problems.

Thank you,


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