OpenCV: Can't find modules from contrib repository (Tracker, selectROI) - c++

Question

I'm working on a project where tracking objects is involved, and I'm trying to get OpenCV contrib repo's TrackerKCF to work. This is the sample code that I got online:
#include <opencv2/core/utility.hpp>
#include <opencv2/video/tracking.hpp>
#include <opencv2/videoio.hpp>
#include <opencv2/highgui.hpp>
#include <iostream>
#include <cstring>
using namespace std;
using namespace cv;
int main( int argc, char** argv ){
// show help
if(argc<2){
cout<<
" Usage: example_tracking_kcf <video_name>\n"
" examples:\n"
" example_tracking_kcf Bolt/img/%04.jpg\n"
" example_tracking_kcf faceocc2.webm\n"
<< endl;
return 0;
}
// create the tracker
Ptr<Tracker> tracker = TrackerKCF::create();
// set input video
std::string video = argv[1];
VideoCapture cap(video);
Mat frame;
// get bounding box
cap >> frame;
Rect2d roi= selectROI("tracker", frame, true, false);
//quit if ROI was not selected
if(roi.width==0 || roi.height==0)
return 0;
// initialize the tracker
tracker->init(frame,roi);
// do the tracking
printf("Start the tracking process, press ESC to quit.\n");
for ( ;; ){
// get frame from the video
cap >> frame;
// stop the program if no more images
if(frame.rows==0 || frame.cols==0)
break;
// update the tracking result
bool isfound = tracker->update(frame,roi);
if(!isfound)
{
cout << "The target has been lost...\n";
waitKey(0);
return 0;
}
// draw the tracked object
rectangle( frame, roi, Scalar( 255, 0, 0 ), 2, 1 );
// show image with the tracked object
imshow("tracker",frame);
//quit on ESC button
if(waitKey(1)==27)break;
}
}
However, I got the following error:
tracktest.cpp: In function ‘int main(int, char**)’:
tracktest.cpp:33:7: error: ‘Tracker’ was not declared in this scope
Ptr<Tracker> tracker = TrackerKCF::create();
^
tracktest.cpp:33:14: error: template argument 1 is invalid
Ptr<Tracker> tracker = TrackerKCF::create();
^
tracktest.cpp:33:26: error: ‘TrackerKCF’ has not been declared
Ptr<Tracker> tracker = TrackerKCF::create();
^
tracktest.cpp:43:54: error: ‘selectROI’ was not declared in this scope
Rect2d roi= selectROI("tracker", frame, true, false);
^
tracktest.cpp:50:10: error: base operand of ‘->’ is not a pointer
tracker->init(frame,roi);
^
tracktest.cpp:63:27: error: base operand of ‘->’ is not a pointer
bool isfound = tracker->update(frame,roi);
^
./tracktest.sh: line 5: ./tracktest: No such file or directory
I tried to reinstall OpenCV 3.1.0 and the corresponding contrib repo, and it seemed thatmake completed just fine. I also tried to locate where tracker.cpp is in my OpenCV source directory, but nothing popped up.
I assume that it's because I've incorrectly installed the contrib modules, but I'm not sure. Can anyone figure out what's wrong? Thanks in advance.

Answer 1

Due to my inexplicable stupidity I forgot to run make install.
It's all good now!