If you have a cmake build folder you (or someone else) used to install OpenCV (and can find the said directory), navigate to that directory and execute in Terminal: $ make uninstall (if brew info opencv shows that opencv is installed) If you’re extremely lucky and you know / remember how you built or installed OpenCV: Installation method If trying to reinstall OpenCV, use the following steps to check for and uninstall previous builds / installations of OpenCV before proceedingĬheck whether OpenCV is installed with pkg-config -modversion opencv echo 'export JAVA_HOME= $(/usr/libexec/java_home -v11 )' >~/.profile

If the output reports Java 11 and Open JDK 11, you’re good to go.Įxecute the following command to add the JAVA_HOME path to ~/.profile.

Now if you return to Terminal and execute sudo java -version again, the pop-up window will have 3 options: Open, Move to Trash, or Cancel. There, you can unblock access to the file. In such case, go to your System Settings > Security. A pop-up window will give you only two choices-move the downloaded file to Trash or cancel operation. Your security setting may block Terminal from correctly accessing Java. Open Terminal and execute the command: sudo java -version Move the extracted openjdk-11 folder to /Library/Java/JavaVirtualMachines/ Navigate to /Library/Java/JavaVirtualMachines/ and delete the jdk folder to uninstall that version of Java.ĭownload and extract openjdk-11_osx-圆4_bin.tar from here or the official website. If the reported version of Java is higher than 11: To check whether you have Java installed, open Terminal and execute command: java -version In this example, we’ll use Java 11 from OpenJDK. Pkg-config helps you keep track of installed packagesįor OpenCV 3.2.0 and JavaGrinders version 56, we recommend Java 11, which is nicely backwards compatible, or Java 1.8. Once Homebrew is installed, install pkg-config as follows (in Terminal): brew install pkg-config (Note: most up-to-date installation instructions can be found on the Homebrew official website.) Install Homebrew, a useful package manager for macOS, by entering the following command in Terminal: /bin/bash -c ' $(curl -fsSL )' Install Xcode following the instructions here. Xcode is a package provided by Apple containing compilers, libraries and additional tools required to develop applications for macOS. Install necessary tools, packages, and dependencies Xcode (If Terminal output says “access denied” or “permission denied”) Type sudo ( superuser do) before the command you want to execute.

(Updated by Scarlet Park) Versions used in this instruction support: Mac OS X Catalina Java (OpenJDK 11) JavaGrinders Library version 56 OpenCV 3.2.0 Eclipse Photon Useful keyboard shortcuts and commands FunctionĮxecute a command in Terminal with superuser privilege JavaGrinders_ARC with OpenCV 3.2.0 and OpenJDK11 - installation support instructions

Jdk mac os catalina