error LNK2019 from OpenCV Tracker

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I tried to use the code form http://docs.opencv.org/3.1.0/d2/d0a/t...

I already compiled opencv_contrib with Cmake and added tracker.hpp into opencv2. After debugging, I got some errors as below:

Error   LNK2019 unresolved external symbol "public: bool __cdecl cv::Tracker::init(class cv::Mat const &,class cv::Rect_<double> const &)" (?init@Tracker@cv@@QEAA_NAEBVMat@2@AEBV?$Rect_@N@2@@Z) referenced in function main
Severity    Code    Description Project File    Line    Suppression State
Error   LNK2019 unresolved external symbol "public: bool __cdecl cv::Tracker::update(class cv::Mat const &,class cv::Rect_<double> &)" (?update@Tracker@cv@@QEAA_NAEBVMat@2@AEAV?$Rect_@N@2@@Z) referenced in function main 
Severity    Code    Description Project File    Line    Suppression State
Error   LNK2019 unresolved external symbol "public: static struct cv::Ptr<class cv::Tracker> __cdecl cv::Tracker::create(class cv::String const &)" (?create@Tracker@cv@@SA?AU?$Ptr@VTracker@cv@@@2@AEBVString@2@@Z) referenced in function main
Severity    Code    Description Project File    Line    Suppression State
Error   LNK2019 unresolved external symbol "class cv::Rect_<double> __cdecl cv::selectROI(class cv::String const &,class cv::Mat,bool,bool)" (?selectROI@cv@@YA?AV?$Rect_@N@1@AEBVString@1@VMat@1@_N2@Z) referenced in function main

Here is the link of LNK2019

I found some information from google that there might be some external symbols, but there was no useful solution to avoid it...I need some suggestions since I have no idea fixing these errors :-(

Thanks a lot!