openCV error : undefined reference to `cvLoadImage' Ubuntu

I have installed the openCV libraries but I am still getting the error $ g++ -I /usr/include/opencv/ -L -lcxcore -lhighgui hello.cpp -o hello /tmp/ccjjrbXr.o: In function `main': hello.cpp:(.text+0x2d): undefined reference to`cvLoadImage' collect2: ld returned 1 exit status When I check for the path of the libraries I get $ pkg-config --libs opencv -lml -lcvaux -lhighgui -lcv -lcxcore I have written a very simple program to test it : ``` enter code here #include< cv.h> #include< highgui.h> /* required to use OpenCV's highgui */ #include< stdio.h> int main() { IplImage* img = 0; printf("Hello\n"); img = cvLoadImage("lena.jpg", 0 ); } ``` There is something wrong with my installation but I am really not able to figure it out. Any guidance will be highly appreciated! Thanks When I run: ``` $ pkg-config --cflags --libs opencv -I/usr/local/include/opencv -I/usr/local/include /usr/local/lib/libopencv_calib3d.so /usr/local/lib/libopencv_contrib.so /usr/local/lib/libopencv_core.so /usr/local/lib/libopencv_features2d.so /usr/local/lib/libopencv_flann.so /usr/local/lib/libopencv_gpu.so /usr/local/lib/libopencv_highgui.so /usr/local/lib/libopencv_imgproc.so /usr/local/lib/libopencv_legacy.so /usr/local/lib/libopencv_ml.so /usr/local/lib/libopencv_nonfree.so /usr/local/lib/libopencv_objdetect.so /usr/local/lib/libopencv_photo.so /usr/local/lib/libopencv_stitching.so /usr/local/lib/libopencv_ts.so /usr/local/lib/libopencv_video.so /usr/local/lib/libopencv_videostab.so ``` But when I run: ``` $ g++ 'pkg-config --cflags --libs opencv' display_image.cpp g++: error: pkg-config --cflags --libs opencv: No such file or directory ``` OpenCV seems to be installed but still the problem persists.