Simple Opencv program with link error on
Hi everyone, I am a Opencv Newbie. I have downloaded and installed Opencv 2.4 according to the instruction, and after that I began writing my first Opencv program, which was basically a copy of the tutorial on the web.
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <iostream>
using namespace cv;
using namespace std;
int main( int argc, char** argv )
{
if( argc != 2)
{
cout <<" Usage: display_image ImageToLoadAndDisplay" << endl;
return -1;
}
Mat image;
image = imread(argv[1], CV_LOAD_IMAGE_COLOR); // Read the file
if(! image.data ) // Check for invalid input
{
cout << "Could not open or find the image" << std::endl ;
return -1;
}
namedWindow( "Display window", CV_WINDOW_AUTOSIZE );// Create a window for display.
imshow( "Display window", image ); // Show our image inside it.
waitKey(0); // Wait for a keystroke in the window
return 0;
}
However, the program has several link errors although compiling seems fine. The link errors I have received are as follows:
Error 2 error LNK2019: unresolved external symbol "void __cdecl cv::namedWindow(class stlp_std::basic_string<char,class stlp_std::char_traits<char>,class stlp_std::allocator<char> > const &,int)" (?namedWindow@cv@@YAXABV?$basic_string@DV?$char_traits@D@stlp_std@@V?$allocator@D@2@@stlp_std@@H@Z) referenced in function _main C:\Research\OpencvTest\OpencvTest.obj
Error 1 error LNK2019: unresolved external symbol "void __cdecl cv::imshow(class stlp_std::basic_string<char,class stlp_std::char_traits<char>,class stlp_std::allocator<char> > const &,class cv::_InputArray const &)" (?imshow@cv@@YAXABV?$basic_string@DV?$char_traits@D@stlp_std@@V?$allocator@D@2@@stlp_std@@ABV_InputArray@1@@Z) referenced in function _main C:\Research\OpencvTest\OpencvTest.obj
Could anyone tell me what's wrong with my program? Thanks!
EDIT: A very tricky part of the problem is that if I use old-style Opencv function I will have no problem at all. The following codes can run very well:
int main( int argc, char** argv )
{
char* filename = "C:\\Research\abc.pgm";
IplImage *img0;
if( (img0 = cvLoadImage(filename,-1)) == 0 )
return 0;
cvNamedWindow( "image", 0 );
cvShowImage( "image", img0 );
cvWaitKey(0);
cvDestroyWindow("image");
cvReleaseImage(&img0);
return 0;
}