Hi, all. I used OpenCV that included in ros-diamondback. I want to use new one, and installed it. sudo apt-get install ros-electric-vision-opencv But, I can't make my programs. Here's return massages . /usr/bin/ld: cannot find -l/usr/lib/libopencv_contrib.so.2.3.1 collect2: ld returned 1 exit status make: *** [cloth_matching] エラー 1 Here's return that 'pkg-config --libs opencv' opencv in diamondback ; pkg-config --libs opencv -L/home/oya/ros/diamondback/vision_opencv/opencv2/opencv/lib -lopencv_core -lopencv_imgproc -lopencv_highgui -lopencv_ml -lopencv_video -lopencv_features2d -lopencv_calib3d -lopencv_objdetect -lopencv_contrib -lopencv_legacy -lopencv_flann Here's return that 'pkg-config --libs opencv-2.3.1' pkg-config --libs opencv-2.3.1 -l/usr/lib/libopencv_contrib.so.2.3.1 -l/usr/lib/libopencv_legacy.so.2.3.1 -l/usr/lib/libopencv_objdetect.so.2.3.1 -l/usr/lib/libopencv_calib3d.so.2.3.1 -l/usr/lib/libopencv_features2d.so.2.3.1 -l/usr/lib/libopencv_video.so.2.3.1 -l/usr/lib/libopencv_highgui.so.2.3.1 -l/usr/lib/libopencv_ml.so.2.3.1 -l/usr/lib/libopencv_imgproc.so.2.3.1 -l/usr/lib/libopencv_flann.so.2.3.1 -l/usr/lib/libopencv_core.so.2.3.1 Why did the return change? I use Ubuntu 10.04. ROS version is electric. __ Ryosuke Oya The Univ. of Tokyo