Install the OpenCV library on Visual Studio

Compiling the libray

There are many benefits of compiling the library from source instead of using the pre-compiled version:

1. Supporting the latest IDE (Vision Studio). For example, pre-compiled OpenCV 3.0 (22/11/2015) is not compatible with Visual Studio 2015.
2. Be able to customize the library, we can add several options to OpenCV, for example, we can add APIs for Kinect SDK, OpenCL, Python, etc.

Down the source code for the Windows environment here.

Step 1: Extract the file into a folder, let say C:\opencv.

Folder build contains pre-compiled DLLs of the library, while filder sources are used for manully installing.

Step 2: Download and install CMake.

Step 3: Run CMake. Where is the soruce code points to folder sources of OpenCV as mentioned in the previous step. Where to build the binaries: where we put output of library, i.e, DLLs files. In this tutorial, I put it in C:\opencv\sources\build.

The next step is to press Configure and later select the generator for the project. In this section, we select the corresponding IDE/Compiler. In addition, if the computer is x86 architecture then we have to select the IDE version which is x86 as well, i.e, Visual Studio 14 2015. If the computer is x64 then we select IDE versions with postfix Win64. Select Finish to complete the configuration.

After that, CMake enumerate all options we can customize. In this tutorial, however, I would skip this part since the goal of this post is to install the default setting and hence other setup will be discuss in other posts. Press Generate to continue.

After generating the source code with selected compiler and IDE, folder build includes different Projects/Solutions.

Step 4: Use Visual Studio to open solution OPENCV. Beware of the version of VS have to be the same of as configured in CMAKE.

Next, we compile the library (press F7):

1. Build the solution with the Debug mode.
2. Build the solution with the Release mode

Each step takes about 10-15 minutes. The output maybe contains 50 successfully complied projects, 17 skipped and 2 fail projects. Visual Studio generates two particulars folders lib\Debug and lib\Release which contain all DLLs for Debug and Release modes, respectively.

Setup OpenCV on Visual Studio

Step 1: Create a new empty project.

Before configuring the project, we have to determine the following information for the project:

1. Header files of OpenCV.
2. Configurate for programming with OpenCV.
3. Configurate for executing the project with OpenCV support. Since there are 2 targets, namely Debug and Release, we have to seperately configurate each target.

Header files

Right click to the project InstallOpencv, select Properties (Alt + F7).

In the sidebar, select C/C++ -> General -> Additional Include Directories, we point to opencv\build\include (NOT sources\build\include). Press OK.

Setup the library for programming

Press Alt + F7 to open dialog Properties of the Project. Select tab Linker, in Additional Library Directories we point to lib\Debug, i.e, C:\opencv\sources\bild\lib\Debug. Nhấn Alt + F7 để vào phần Properties của Project. Chọn Thẻ Linker, mục Additional Library Directories ta trỏ đến thư mục lib\Debug (trong ví dụ này là: C:\oepncv\sources\build\lib\Debug) since we are using the Debug target.

Move to tab Input, select Additional Dependencies, we input these files:

opencv_calib3d300d.lib
opencv_core300d.lib
opencv_features2d300d.lib
opencv_flann300d.lib
opencv_hal300d.lib
opencv_highgui300d.lib
opencv_imgcodecs300d.lib
opencv_imgproc300d.lib
opencv_ml300d.lib
opencv_objdetect300d.lib
opencv_photo300d.lib
opencv_shape300d.lib
opencv_stitching300d.lib
opencv_superres300d.lib
opencv_ts300d.lib
opencv_video300d.lib
opencv_videoio300d.lib
opencv_videostab300d.lib

Next, we move to the Release target and repeat previous steps. However, the path now is C:\opencv\sources\build\lib\Release.

Additional Dependencies are:

opencv_calib3d300.lib
opencv_core300.lib
opencv_features2d300.lib
opencv_flann300.lib
opencv_hal300.lib
opencv_highgui300.lib
opencv_imgcodecs300.lib
opencv_imgproc300.lib
opencv_ml300.lib
opencv_objdetect300.lib
opencv_photo300.lib
opencv_shape300.lib
opencv_stitching300.lib
opencv_superres300.lib
opencv_ts300.lib
opencv_video300.lib
opencv_videoio300.lib
opencv_videostab300.lib

Setup the library for running the code

While building the project, Visual Studio creates two new folders of the solution: \Debug and \Release with the architecture name we are using. In this example, they are x64\Debug and x64\Release. We copy all files from build\bin\Debug to x64\Debug, also files in build\bin\Release to x64\Release.

Create an example and run the program.

#include <opencv2/opencv.hpp>
#include <iostream>
using namespace cv;
using namespace std;

int main() {
    Mat img = imread("demo.jpg");
    imshow("show image", img);
    waitKey(0);
    destroyAllWindows();
}

[Place demo.jpg in the project folder to run the code]

However

There are many drawbacks here:

1. Every time we create a project including OpenCV support, we have to follow these settings (Section 2). It is tedious. One mistake can cost us several hours to figure out.
2. The size of library files in sources\bin\Debug and source\bin\Release are approximately 900MB each. Copying two libraries to the project takes 1.8GB even though the source code alone only cost several KBs.
3. How we can get all file names of Additional Dependencies since each OpenCV version has different files.

Let see how we can resolve these problems.

Additional Dependencies

Open the command line and point to sources\build\lib:

Type these commands:

dir Debug\*d.lib /B >..\DependenciesDebug.txt
dir Release\*.lib /B >..\DependenciesRelease.txt

All files are saved in DependenciesDebug.txt and DependenciesRelease.txt. We simply copy the content to Additional Dependencies when creating a new project.

Library Configuration

Open the Command Line with Admin permission, type these commands:

 setx -m OPENCV_DIR C:\opencv

Windows + E to open File Explorer Nhấn Windows E để mở Windows Explore

Right click on Computer and select Properties.

Select Advanced System Settings. In tab Advanced, select Environment Variables…

Fill these values: %OPENCV_DIR%\sources\build\bin\Debug;%OPENCV_DIR%\sources\build\bin\Release

Done, henceforth, we do not have to copy files from build\bin to the project.

Saving configuration of the project

In the sidebar Property Manager, we seethe list of all configs corresponding to target archtectures in the project.

We create a new Property Sheet by right clicking into each section and selecting Add New Project Property Sheet. Double click to the new sheet and configure as mentioned in Section 2. Visual Studio will create a new file with extension props in the project. Henceforth, while creating a new project, we only need to import the Property.

Since we set the variable path being OPENCV_DIR, we can change the paths in the configuraton as following:

    %OPENCV_DIR%\build\include
    %OPENCV_DIR%\source\build\lib\Debug
    %OPENCV_DIR%\source\build\lib\Release