Digital Image Processing Applications in Java Using OpenCV

Integrating OpenCV to NetBeans IDE in Windows

OpenCV is a programming function library primarily geared towards real-time computer vision. It was created by Intel and was subsequently sponsored by Willow Garage and Itseez. The library is cross-platform and free to use under the Apache 2 License, which is open source.

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Usually, we would have seen many articles based on OpenCV and Python. In this article, let’s see how we can integrate OpenCV in NetBeans IDE so that we can make Digital Image Processing applications in Java.

Contents of this article

∘ 1 — Install the latest Java version
∘ 2 — Install NetBeans IDE
∘ 3 — Download and extract OpenCV
∘ 4 — Set up OpenCV for Java in NetBeans IDE
∘ 5 — RGB to Grayscale implementation in Java

This article will walk you through the process of installing OpenCV on your desktop operating system, setting up with NetBeans IDE, and converting an RGB image to Grayscale using Java and OpenCV.

1 — Install the latest Java version

Download the most recent Java JDK from Oracle’s website.

2 — Install NetBeans IDE

Download the most recent NetBeans IDE.

3 — Download and extract OpenCV

First and foremost, you need to obtain the OpenCV library (version 4.x). Then, extract the downloaded OpenCV file to a convenient location. Once you’ve obtained the folder opencv, place it wherever you like. The only items you’ll need now are the opencv-4xx.jar file from opencv/build/java and the opencv_java4xx.dll library from opencv/build/java/x64 (for 64-bit platforms) or opencv/build/java/x86 (for 32-bit systems). Each file’s 4xx suffix is a shorthand for the current OpenCV version, for example, 400 for OpenCV 4.0 and 452 for OpenCV 4.5.2.

4 — Set up OpenCV for Java in NetBeans IDE

Right-click on the Libraries section under your project name and click Add Library.

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Click Create;

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Give a name for the Library you want to add like this.

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Select Add JAR/Folder

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Find and select the opencv-452.jar

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Click Add JAR/Folder and complete the rest of the dialogue boxes.

Go to the project’s properties by right-clicking the project file.

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Select Run and paste the following inside the VM Options area.

-Djava.library.path="Path for opencv_java4xx.dll"

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5 — RGB to Grayscale implementation in Java

Now create a class with ColorToGrayscale as the class name and paste this code

Input image

Image from http://www.lenna.org/

What would be the output?

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Now you have learned that we can use OpenCV with Java too in NetBeans IDE. This is also possible for Eclipse IDE. Try to implement some Digital Image Processing Applications in Java. Also, try to implement Morphological Operations in Digital Image Processing in Java.

Hope this can help. Share your thoughts too.