Background
OpenCV (Open Source Computer Vision Library) is a very strong Computer Vision Library using in industry. OpenCV is originally written in C++ but it also can be used by Python, JAVA and MATLAB. Written in optimized C/C++, the library can take advantage of multi-core processing. Enabled with OpenCL, it can take advantage of the hardware acceleration of the underlying heterogeneous compute platform.
Below two articles are very good reference for setting up opencv in Mac for c++ development. The first one compiles the source code to install the library. The second one uses homebrew to install the opencv. Really thanks for sharing your knowledge! In this article, I will focus on the issues I hit when I install the libraries.
Issues & Solutions
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‘array’ file not found in cvdef.h
The issue is because
arrayis provided in C++11, you need to provide the -std=c++11 flag to enable it, and provide the-stdlib=libc++flag for the corresponding library. But in the article one, we need to chooselibstdc++. So there is a conflict here, that’s why finally I choose to use the command Line Method in article 2.
-
macports for gcc upgrade
my previous gcc version is 4.2 and I use macports to upgrade it to 4.7 to make sure it to support
C++11. You can refer to below article to upgrade your gcc in mac. -
pkg-config –cflags –libs opencv not found
As mentioned in article 2, if
pkg-config --cflags --libs opencvdoesn’t work, you should specify the location of your opencv.pc path. Also you need to add it to your~/.bash_profileand apply it.#pk_package path as below
export PKG_CONFIG_PATH=/usr/local/lib/pkgconfig:/usr/local/lib:/usr/local/Cellar/opencv/3.4.3_1/lib/pkgconfig/ -
glog Library not loaded
After you build your program, when you run your program, it maybe report below error:
dyld: Library not loaded: /usr/local/opt/glog/lib/libglog.0.3.5.dylib
Referenced from: /usr/local/opt/opencv/lib/libopencv_sfm.3.4.dylib
Reason: image not found
Abort trap: 6This issue is because you need to install
glogseparately.brew install glog
Testing Program
#include <iostream>
#include <opencv2/opencv.hpp>
#include <opencv2/highgui.hpp>
using namespace std;
using namespace cv;
int main(int argc, const char * argv[]) {
Mat image;
//change to your own path
image = imread("/Users/micah/Downloads/1.jpg", 1);
namedWindow("Display Image", WINDOW_AUTOSIZE);
imshow("Display Image", image);
waitKey(0);
return 0;
}
