Setting Up and Running OpenCV C++ Programs with VS Code and CMake

Introduction

• Tutorial covers:
  • Installing CMake
  • Installing OpenCV
  • Setting up environment variables
  • Overview of CMakeLists.txt
  • Simple OpenCV program in C++
  • Configure step
  • Build and debug
  • Build and release
  • Modify program and rebuild
• Channel topics: OpenCV, computer vision, Python, C++, Git, ROS 2, SolidWorks, mechanical design
• GitHub repository available for resources

Installing CMake

• Go to CMake website
• For Windows (64-bit): download and run the Windows x64 installer

Installing OpenCV

• Download OpenCV version 4.8.0
• From the website, click on Windows and download the .exe file
• Save the file in your desired path (e.g., opt path)
• The downloaded OpenCV folder contains:
  • bin folder
  • lib folder

Setting Up Environment Variables

• Create a variable OpenCV_DIR and set its value to the location of the OpenCV build folder
• Add the following to the system Path environment variables:
  • CMake/bin
  • OpenCV/bin
  • OpenCV/lib
• Instructions for accessing environment variables in Windows:
  • Press Windows key, type “system environment”, go to Environment Variables
  • Declare the variable and its value
  • Add paths to the system Path

CMakeLists.txt Overview

• Example CMakeLists.txt file:
  • Specify minimum CMake version: cmake_minimum_required
  • Name the project: project(OpenCVExample)
  • Find OpenCV package: find_package(OpenCV REQUIRED)
  • Include necessary directories: include_directories
  • Add executable: add_executable
  • Link OpenCV libraries: target_link_libraries

Simple OpenCV C++ Program

• Example code structure:
  • Main function: int main()
  • Read image: cv::imread("path/to/image")
  • Display image: cv::imshow("Display Image", img)
  • Wait for key press: cv::waitKey(0)

Configure Step

• Create a build directory: mkdir build
• Navigate to the build directory: cd build
• Run CMake configure command: cmake ..
  • Specifying Visual Studio version, Windows SDK, compilers
  • Generates build files like .sln, CMakeCache.txt, and project files

Build and Debug

• Build command for debug: cmake --build . --config Debug
• Run the executable: build/Debug/OpenCVExample.exe
• Example output: Displays the image read by the program

Build and Release

• Build command for release: cmake --build . --config Release
• Run the executable in release mode: build/Release/OpenCVExample.exe
• Release mode is optimized for performance

Modify Program and Rebuild

• Change the image path or code in main()
• Rebuild the project: cmake --build .
• Run the new executable: build/Debug/OpenCVExample.exe

Conclusion

• Like and subscribe for more tutorials

[Music]