Install OpenCV 3 on Windows

本是古典何须时尚 2022-05-17 05:29 190阅读 0赞

# Install OpenCV 3 on Windows #

原文链接：[https://www.learnopencv.com/install-opencv3-on-windows/][https_www.learnopencv.com_install-opencv3-on-windows]

MAY 26, 2017 BY [VAIBHAW SINGH CHANDEL][] [90 COMMENTS][]

[![Install OpenCV 3 on Windows][]][Install OpenCV 3 on Windows]

In this post, we will provide step by step instructions on how to install OpenCV 3 (C++ and Python) on Windows. However, we have found that a lot of readers want to install for python only. So, if you want to install OpenCV 3.3 for **python only**, please follow [this post][].

We have used Windows Power Shell to run commands. Alternatively, you can use the command prompt too.

## Step 1: Install Visual Studio ##

Download and install Visual Studio 2015 community edition from [https://www.visualstudio.com/vs/older-downloads/][https_www.visualstudio.com_vs_older-downloads]. If you are finding it difficult to search for Visual Studio 2015, use this [link][]. If you don’t have a Visual Studio Dev Essentials account, create account and login. Run installer, select “Custom” in “type of installation”.

[![opcv-windows-custom.png][]][opcv-windows-custom.png]

In next screen within Programming Languages, select Visual C++ and Python tools for Visual Studio. Click next.

[![opcv-windows-programmingLanguage.png][]][opcv-windows-programmingLanguage.png]

Now click next. It will take some time to complete the installation.

[![opcv-windows-launch.png][]][opcv-windows-launch.png]

We have finished installation of Visual Studio 2015.

**Note:** Since Visual Studio 2017 fails to compile Dlib, we switched back to Visual Studio 2015.

## Step 2: Install CMake ##

Download and install CMake v3.10.0 from [https://cmake.org/download/][https_cmake.org_download].

[![opcv-windows-cmake-platform.png][]][opcv-windows-cmake-platform.png]

During installation select “Add CMake to system PATH”

[![opcv-windows-cmakeinsatlloptions.png][]][opcv-windows-cmakeinsatlloptions.png]

## Step 3: Install Anaconda (a python distribution) ##

Download and install Anaconda 64-bit version from [https://www.continuum.io/downloads][https_www.continuum.io_downloads].

**Note:** Dlib ships a prebuilt binary for Python 3 and not Python 2. Building Dlib’s Python bindings from source is a hassle as you have to build Boost.Python first.  
So it is advised to install Anaconda 3. In case you want to build OpenCV’s Python bindings for Python 2, you can install Anaconda 2 as well but you won’t be able to use Dlib in Python 2.

[![Download and Install 64-bit Anaconda 2 or Anaconda 3 or both][]][Download and Install 64-bit Anaconda 2 or Anaconda 3 or both 1]

While installing Anaconda make sure that you check both options:

1.  Add Anaconda to my PATH environment variable
2.  Register Anaconda as my default Python

[![Add Anaconda to System PATH and make it default Python][]][Add Anaconda to System PATH and make it default Python 1]

## Step 4: Download and extract opencv-3.3.1 and opencv\_contrib-3.3.1 ##

Go to [https://github.com/opencv/opencv/releases][https_github.com_opencv_opencv_releases] and download opencv-3.3.1 source code zip

[![opcv-windows-opencv3.3.1-1.png][]][opcv-windows-opencv3.3.1-1.png]

Go to [https://github.com/opencv/opencv\_contrib/releases][https_github.com_opencv_opencv_contrib_releases] and download opencv\_contrib-3.3.1 source code zip

[![opcv-windows-opencvContrib3.3.1-1.png][]][opcv-windows-opencvContrib3.3.1-1.png]  
Extract both zip files. Although you can keep opencv and opencv\_contrib folders anywhere, I suggest that you should keep both in the same directory. I have placed these two folders in “My Documents” directory.

**NOTE :** From hereon we will refer the path to opencv-3.3.1 folder as **OPENCV\_PATH**. For example, in my case OPENCV\_PATH is C:/Users/Vaibhaw Chandel/Documents/opencv-3.3.1

Depending upon where you have kept opencv-3.3.1 folder, this path would be different.

[![Extract OpenCV 3.2.0 and OpenCV contrib 3.2.0 to same folder][]][Extract OpenCV 3.2.0 and OpenCV contrib 3.2.0 to same folder 1]

## Step 5: Generate Visual Studio project using CMake ##

Run Cmake, in box “Where is the source code” write value of **OPENCV\_PATH**(which is path to opencv-3.3.1 folder) and path to build directory. We will choose build directory as **OPENCV\_PATH**/build

[![opcv-windows-cmake-path2.png][]][opcv-windows-cmake-path2.png]

Now click configure.  
You will be asked for permission to create the build folder. Click Yes.

[![opcv-windows-createbuild-cmake2.png][]][opcv-windows-createbuild-cmake2.png]

When prompted to select a compiler, select **Visual Studio 14 2015 Win64**.  
[![opcv-windows-selectCompiler.png][]][opcv-windows-selectCompiler.png]

Click finish and in the next window keep the default parameters checked.

[![opcv-windows-cmake-default-parameters.png][]][opcv-windows-cmake-default-parameters.png]

Click finish. Now CMake will look in the system directories and generate the makefiles.

### Step 5.1: Additional changes to CMake config ###

We will make few changes in the default configuration generated by CMake. Click on the images to see a larger version.

Now click configure to apply these changes.

[![opcv-windows-cmake-additionalConfiguration1.png][]][opcv-windows-cmake-additionalConfiguration1.png]

[![opcv-windows-cmake-additionalConfiguration2.png][]][opcv-windows-cmake-additionalConfiguration2.png]

1.  Check “INSTALL\_C\_EXAMPLES” and “INSTALL\_PYTHON\_EXAMPLES”
2.  In flag “OPENCV\_EXTRA\_MODULES\_PATH”, give path of modules directory within opencv\_contrib-3.3.1. In our case we have kept opencv\_contrib-3.3.1 in Documents folder so path is “C:/Users/Vaibhaw Chandel/Documents/opencv\_contrib-3.3.1/modules”
3.  On Windows 10, opencv\_saliency module fails to build. So we will disable it. **Uncheck BUILD\_opencv\_saliency**

Now click on configure again to include this change.

### Step 5.2 : Add Python paths for both Python2 and Python3 (optional) ###

This section is only for people who want to generate OpenCV binary for both Python2 and Python 3. If you are going to use just one Python either 2 or 3, you should skip this section.

CMake was unable to find paths for my Python3 files.

[![Configure Python flags for OpenCV build files][]][Configure Python flags for OpenCV build files 1]

So I manually added paths for Python3.

[![Added Python 3 paths in CMake][]][Added Python 3 paths in CMake 1]

Now click configure again. After configuring is done, search **opencv\_python** in search bar, both **BUILD\_opencv\_python2** and **BUILD\_opencv\_python3** will be automatically checked. Now we are sure that OpenCV binaries for both Python2 and Python 3 will be generated after compilation.

[![Check which Python (2 or 3 or both) builds will be generated][Check which Python _2 or 3 or both_ builds will be generated]][Check which Python _2 or 3 or both_ builds will be generated_Check which Python _2 or 3 or both_ builds will be generated]

### Step 5.3 : Generate build files ###

If CMake is able to configure without any errors it should say “Configuring done”.  
Click generate.

**Note:** Whenever you make any changes(check/uncheck boxes or change path) to configuration generated by CMake, always click configure and generate.

## Step 6: Compile OpenCV ##

### Step 6.1:Compile opencv in Release mode ###

Open Windows Command Prompt (cmd).  
Go to OPENCV\_PATH/build directory and run this command

<table> 
 <tbody> 
  <tr> 
   <td> <p>1</p> </td> 
   <td> <p><code>cmake.exe --build . --config Release --target INSTALL</code></p> </td> 
  </tr> 
 </tbody> 
</table>

### Step 6.2 : Compile opencv in Debug mode ###

Open CMake GUI again as mentioned in Step 5.

1.  Search “python” in search box
2.  Uncheck INSTALL\_PYTHON\_EXAMPLES, BUILD\_opencv\_python3 and BUILD\_opencv\_python2
3.  Click configure
4.  Click generate

Now in windows command prompt  
Go to OPENCV\_PATH/build directory and run this command

<table> 
 <tbody> 
  <tr> 
   <td> <p>1</p> </td> 
   <td> <p><code>cmake.exe --build . --config Debug --target INSTALL</code></p> </td> 
  </tr> 
 </tbody> 
</table>

Now that we have compiled OpenCV we will find out how to test a OpenCV project using CMake.

## Step 7: Update System Environment Variables ##

### Step 7.1 : Update environment variable – PATH ###

First of all we will add OpenCV dll files’ path to our system PATH. Press Windows Super key, search for “environment variables”

[![opcv-windows-searchEnvVariable.png][]][opcv-windows-searchEnvVariable.png]

Click Environment Variables in System Properties window

[![opcv-windows-SelectenvVariable.png][]][opcv-windows-SelectenvVariable.png]

Under System Variables, Select Path and click edit

[![opcv-windows-pathEdit-envVariable-e1511624440119.png][]][opcv-windows-pathEdit-envVariable-e1511624440119.png]

Click New, and give path to **OPENCV\_PATH**\\build\\install\\x64\\vc14\\bin and click Ok. Depending upon where you have kept opencv-3.3.1 folder and what version of Visual Studio you used to compile OpenCV, this path would be different. In my case full path is:  
C:\\Users\\Vaibhaw Chandel\\Documents\\opencv-3.3.1\\build\\install\\x64\\vc14\\bin

[![opcv-windows-opencvPath-envVariable-e1511624367231.png][]][opcv-windows-opencvPath-envVariable-e1511624367231.png]

Now click Ok to save. Don’t close the Environment Variables window yet. We will update OPENCV\_DIR variable in next step.

### Step 7.2 : Update user environment variable – OPENCV\_DIR ###

[![opcv-windows-envVariable-new.png][]][opcv-windows-envVariable-new.png]

Click New in “User Variables” (upper half of right hand side window). Under variable name write OPENCV\_DIR and under variable value write **OPENCV\_PATH**\\build\\install.

As you can see in my case variable value is:  
C:\\Users\\Vaibhaw Chandel\\Documents\\opencv-3.3.1\\build\\install  
This directory contains file “OpenCVConfig.cmake”. This is used by CMake to configure OpenCV\_LIBS and OpenCV\_INCLUDE\_DIRS variables to generate project files.

[![opcv-windows-envVariable-OPENCVDIR-e1511624233526.png][]][opcv-windows-envVariable-OPENCVDIR-e1511624233526.png]  
Now click ok to save and close environment variables window.

[![opcv-windows-EnvVraiable.png][]][opcv-windows-EnvVraiable.png]

**Note:** If you have an open Command Prompt/Power Shell window before these values were updated, you have to close and open a new Command Prompt/Power Shell window again.

## Step 8: Testing C++ code ##

Download [this redEyeRemover code][] and extract it into a folder.  
Now open Windows Power Shell and navigate to this directory.  
Create a file named CMakeLists.txt and put this code in this file.

<table> 
 <tbody> 
  <tr> 
   <td> <p>1</p> <p>2</p> <p>3</p> <p>4</p> <p>5</p> <p>6</p> </td> 
   <td> <p><code>cmake_minimum_required(VERSION 2.8)</code></p> <p><code>project( redEyeRemover )</code></p> <p><code>find_package( OpenCV REQUIRED )</code></p> <p><code>include_directories( ${OpenCV_INCLUDE_DIRS} )</code></p> <p><code>add_executable( removeRedEyes removeRedEyes.cpp )</code></p> <p><code>target_link_libraries( removeRedEyes ${OpenCV_LIBS} )</code></p> </td> 
  </tr> 
 </tbody> 
</table>

CMakeLists.txt的内容需要修改成下面的code才能成功，不知道是不是自己编译的时候设置的不对....

cmake_minimum_required(VERSION 2.8)
    project( redEyeRemover )
    set( OpenCV_DIR  E:\\Go\\SLAM\\implementation\\cv3.3.1 )
    find_package( OpenCV REQUIRED )
    set( OpenCV_FOUND 1 )
    include_directories( ${OpenCV_INCLUDE_DIRS} )
    add_executable( removeRedEyes removeRedEyes.cpp )
    target_link_libraries( removeRedEyes ${OpenCV_LIBS} )

This file has information about opencv’s include and library paths.

[![opcv-windows-powershell-Redeyeremover.png][]][opcv-windows-powershell-Redeyeremover.png]  
Now we will compile removeRedEyes.cpp and run it.

<table> 
 <tbody> 
  <tr> 
   <td> <p>1</p> <p>2</p> <p>3</p> <p>4</p> <p>5</p> </td> 
   <td> <p><code># create build directory</code></p> <p><code>mkdir build</code></p> <p><code>cd build</code></p> <p><code># create Visual Studio project files using cmake</code></p> <p><code>cmake </code><code>-</code><code>G </code><code>"Visual Studio 14 2015 Win64"</code> <code>..</code></p> </td> 
  </tr> 
 </tbody> 
</table>

You can see in the screenshot below that CMake found the OpenCV on my machine.  
[![opcv-windows-createvsProject.png][]][opcv-windows-createvsProject.png]

Now we will build our application.

<table> 
 <tbody> 
  <tr> 
   <td> <p>1</p> <p>2</p> <p>3</p> </td> 
   <td> <p><code># build our application</code></p> <p><code>cmake </code><code>-</code><code>-</code><code>build . </code><code>-</code><code>-</code><code>config Release</code></p> <p><code># once the build is complete, it will generate exe file in build\Release directory</code></p> </td> 
  </tr> 
 </tbody> 
</table>

[![opcv-windows-buildingapp-cpp.png][]][opcv-windows-buildingapp-cpp.png]

Since our C++ code assumes that jpg files are in the current directory, we will move to directory RedEyeRemover and run removeRedEyes.exe file from there.

<table> 
 <tbody> 
  <tr> 
   <td> <p>1</p> <p>2</p> </td> 
   <td> <p><code>cd ..</code></p> <p><code>.\build\Release\removeRedEyes.exe</code></p> </td> 
  </tr> 
 </tbody> 
</table>

After running the application you will see two image windows, one with red eyes and another with black eyes.  
[![opcv-windows-cpp-test-e1511624146531.png][]][opcv-windows-cpp-test-e1511624146531.png]

## Step 9: Testing Python code ##

### Step 9.1 : Quick check ###

Quick way to check whether OpenCV for Python is installed correctly or not is to import cv2 in python interpreter.  
Open command prompt in Windows, run python command. This will open Python interpreter. Run these two commands

<table> 
 <tbody> 
  <tr> 
   <td> <p>1</p> <p>2</p> </td> 
   <td> <p><code>import</code> <code>cv2</code></p> <p><code>print</code><code>(cv2.__version__)</code></p> </td> 
  </tr> 
 </tbody> 
</table>

Anaconda comes with a feature-rich Python interpreter called IPython. I tested these commands in IPython.

[![opcv-windows-python-version.png][]][opcv-windows-python-version.png]  
If OpenCV for Python is installed correctly, running command “import cv2” will give no errors. If any error comes up it means installation failed.

### Step 9.2 : Testing redEyeRemover application ###

Open Windows Power Shell and navigate to directory where you have extracted RedEyeRemover.zip  
Now run python code like this:

<table> 
 <tbody> 
  <tr> 
   <td> <p>1</p> </td> 
   <td> <p><code>python .\removeRedEyes.py</code></p> </td> 
  </tr> 
 </tbody> 
</table>

If the program runs successfully, you will see two image windows one with red-eyes other with black eyes.  
[![opcv-windows-pythoncode-test-e1511624067214.png][]][opcv-windows-pythoncode-test-e1511624067214.png]

FILED UNDER: [COMPILE][], [INSTALL][], [OPENCV 3][] TAGGED WITH: [OPENCV 3][OPENCV 3 1], [WINDOWS][]

[https_www.learnopencv.com_install-opencv3-on-windows]: https://www.learnopencv.com/install-opencv3-on-windows/
[VAIBHAW SINGH CHANDEL]: https://www.learnopencv.com/author/vaibhawchandel/
[90 COMMENTS]: https://www.learnopencv.com/install-opencv3-on-windows/#disqus_thread
[Install OpenCV 3 on Windows]: https://www.learnopencv.com/wp-content/uploads/2017/05/install-opencv-3-on-windows.jpg
[this post]: https://www.learnopencv.com/install-opencv-3-and-dlib-on-windows-python-only/
[https_www.visualstudio.com_vs_older-downloads]: https://www.visualstudio.com/vs/older-downloads/
[link]: https://my.visualstudio.com/Downloads?pid=2086
[opcv-windows-custom.png]: https://www.learnopencv.com/wp-content/uploads/2017/11/opcv-windows-custom.png
[opcv-windows-programmingLanguage.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-programmingLanguage.png
[opcv-windows-launch.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-launch.png
[https_cmake.org_download]: https://cmake.org/download/
[opcv-windows-cmake-platform.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-cmake-platform.png
[opcv-windows-cmakeinsatlloptions.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-cmakeinsatlloptions.png
[https_www.continuum.io_downloads]: https://www.continuum.io/downloads
[Download and Install 64-bit Anaconda 2 or Anaconda 3 or both]: https://www.learnopencv.com/wp-content/uploads/2017/05/opencv_0010-1024x576.png
[Download and Install 64-bit Anaconda 2 or Anaconda 3 or both 1]: https://www.learnopencv.com/wp-content/uploads/2017/05/opencv_0010.png
[Add Anaconda to System PATH and make it default Python]: https://www.learnopencv.com/wp-content/uploads/2017/05/opencv_0016-1024x576.png
[Add Anaconda to System PATH and make it default Python 1]: https://www.learnopencv.com/wp-content/uploads/2017/05/opencv_0016.png
[https_github.com_opencv_opencv_releases]: https://github.com/opencv/opencv/releases
[opcv-windows-opencv3.3.1-1.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-opencv3.3.1-1.png
[https_github.com_opencv_opencv_contrib_releases]: https://github.com/opencv/opencv_contrib/releases
[opcv-windows-opencvContrib3.3.1-1.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-opencvContrib3.3.1-1.png
[Extract OpenCV 3.2.0 and OpenCV contrib 3.2.0 to same folder]: https://www.learnopencv.com/wp-content/uploads/2017/05/opencv_0022-1024x575.png
[Extract OpenCV 3.2.0 and OpenCV contrib 3.2.0 to same folder 1]: https://www.learnopencv.com/wp-content/uploads/2017/05/opencv_0022.png
[opcv-windows-cmake-path2.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-cmake-path2.png
[opcv-windows-createbuild-cmake2.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-createbuild-cmake2.png
[opcv-windows-selectCompiler.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-selectCompiler.png
[opcv-windows-cmake-default-parameters.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-cmake-default-parameters.png
[opcv-windows-cmake-additionalConfiguration1.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-cmake-additionalConfiguration1.png
[opcv-windows-cmake-additionalConfiguration2.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-cmake-additionalConfiguration2.png
[Configure Python flags for OpenCV build files]: https://www.learnopencv.com/wp-content/uploads/2017/05/opencv_0049-1024x544.png
[Configure Python flags for OpenCV build files 1]: https://www.learnopencv.com/wp-content/uploads/2017/05/opencv_0049.png
[Added Python 3 paths in CMake]: https://www.learnopencv.com/wp-content/uploads/2017/05/opencv_0055-1024x555.png
[Added Python 3 paths in CMake 1]: https://www.learnopencv.com/wp-content/uploads/2017/05/opencv_0055.png
[Check which Python _2 or 3 or both_ builds will be generated]: https://www.learnopencv.com/wp-content/uploads/2017/05/opencv_0064-1024x557.png
[Check which Python _2 or 3 or both_ builds will be generated_Check which Python _2 or 3 or both_ builds will be generated]: https://www.learnopencv.com/wp-content/uploads/2017/05/opencv_0064.png
[opcv-windows-searchEnvVariable.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-searchEnvVariable.png
[opcv-windows-SelectenvVariable.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-SelectenvVariable.png
[opcv-windows-pathEdit-envVariable-e1511624440119.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-pathEdit-envVariable-e1511624440119.png
[opcv-windows-opencvPath-envVariable-e1511624367231.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-opencvPath-envVariable-e1511624367231.png
[opcv-windows-envVariable-new.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-envVariable-new.png
[opcv-windows-envVariable-OPENCVDIR-e1511624233526.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-envVariable-OPENCVDIR-e1511624233526.png
[opcv-windows-EnvVraiable.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-EnvVraiable.png
[this redEyeRemover code]: https://www.filepicker.io/api/file/XV6a0s3HQ3ybXXhRNvVy
[opcv-windows-powershell-Redeyeremover.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-powershell-Redeyeremover.png
[opcv-windows-createvsProject.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-createvsProject.png
[opcv-windows-buildingapp-cpp.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-buildingapp-cpp.png
[opcv-windows-cpp-test-e1511624146531.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-cpp-test-e1511624146531.png
[opcv-windows-python-version.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-python-version.png
[opcv-windows-pythoncode-test-e1511624067214.png]: https://www.learnopencv.com/wp-content/uploads/2017/05/opcv-windows-pythoncode-test-e1511624067214.png
[COMPILE]: https://www.learnopencv.com/category/compile/
[INSTALL]: https://www.learnopencv.com/category/install/
[OPENCV 3]: https://www.learnopencv.com/category/opencv-3/
[OPENCV 3 1]: https://www.learnopencv.com/tag/opencv-3/
[WINDOWS]: https://www.learnopencv.com/tag/windows/