How to compare two images using Java OpenCV library?
Compare two images -
Read them using the Image.IO.read() method.
Get the height and width of both, making sure they are equal.
Get the pixel value and get the RGB value of the two images.
-
Get the sum of the differences between the RGB values of these two images.
li> Use the following formula to calculate the percentage of difference -
Average = difference/weight*height*3; Percentage = (Average/255)*100;
Example
import java.awt.Color;
import java.awt.image.BufferedImage;
import javax.imageio.ImageIO;
import java.io.File;
public class ComparingImages {
public static void main(String[] args) throws Exception {
BufferedImage img1 = ImageIO.read(new File("D:\Images\test1.jpg"));
BufferedImage img2 = ImageIO.read(new File("D:\Images\test2.jpg"));
int w1 = img1.getWidth();
int w2 = img2.getWidth();
int h1 = img1.getHeight();
int h2 = img2.getHeight();
if ((w1!=w2)||(h1!=h2)) {
System.out.println("Both images should have same dimwnsions");
} else {
long diff = 0;
for (int j = 0; j < h1; j++) {
for (int i = 0; i < w1; i++) {
//Getting the RGB values of a pixel
int pixel1 = img1.getRGB(i, j);
Color color1 = new Color(pixel1, true);
int r1 = color1.getRed();
int g1 = color1.getGreen();
int b1 = color1.getBlue();
int pixel2 = img2.getRGB(i, j);
Color color2 = new Color(pixel2, true);
int r2 = color2.getRed();
int g2 = color2.getGreen();
int b2= color2.getBlue();
//sum of differences of RGB values of the two images
long data = Math.abs(r1-r2)+Math.abs(g1-g2)+ Math.abs(b1-b2);
diff = diff+data;
}
}
double avg = diff/(w1*h1*3);
double percentage = (avg/255)*100;
System.out.println("Difference: "+percentage);
}
}
}Input 1
Input 2

Output
Difference: 92.54901960784314
The above is the detailed content of How to compare two images using Java OpenCV library?. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undress AI Tool
Undress images for free
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Comparing Java Frameworks: Spring Boot vs Quarkus vs Micronaut
Aug 04, 2025 pm 12:48 PM
Pre-formanceTartuptimeMoryusage, Quarkusandmicronautleadduetocompile-Timeprocessingandgraalvsupport, Withquarkusoftenperforminglightbetterine ServerLess scenarios.2.Thyvelopecosyste,
What is a deadlock in Java and how can you prevent it?
Aug 23, 2025 pm 12:55 PM
AdeadlockinJavaoccurswhentwoormorethreadsareblockedforever,eachwaitingforaresourceheldbytheother,typicallyduetocircularwaitcausedbyinconsistentlockordering;thiscanbepreventedbybreakingoneofthefournecessaryconditions—mutualexclusion,holdandwait,nopree
How to join an array of strings in Java?
Aug 04, 2025 pm 12:55 PM
Using String.join() (Java8) is the easiest recommended method for connecting string arrays, just specify the separator directly; 2. For old versions of Java or when more control is needed, you can use StringBuilder to manually traverse and splice; 3. StringJoiner is suitable for scenarios that require more flexible formats such as prefixes and suffixes; 4. Using Arrays.stream() combined with Collectors.joining() is suitable for filtering or converting the array before joining; To sum up, if Java8 and above is used, the String.join() method should be preferred in most cases, which is concise and easy to read, but for complex logic, it is recommended.
How to implement a simple TCP client in Java?
Aug 08, 2025 pm 03:56 PM
Importjava.ioandjava.net.SocketforI/Oandsocketcommunication.2.CreateaSocketobjecttoconnecttotheserverusinghostnameandport.3.UsePrintWritertosenddataviaoutputstreamandBufferedReadertoreadserverresponsesfrominputstream.4.Usetry-with-resourcestoautomati
How to compare two strings in Java?
Aug 04, 2025 am 11:03 AM
Use the .equals() method to compare string content, because == only compare object references rather than content; 1. Use .equals() to compare string values equally; 2. Use .equalsIgnoreCase() to compare case ignoring; 3. Use .compareTo() to compare strings in dictionary order, returning 0, negative or positive numbers; 4. Use .compareToIgnoreCase() to compare case ignoring; 5. Use Objects.equals() or safe call method to process null strings to avoid null pointer exceptions. In short, you should avoid using == for string content comparisons unless it is explicitly necessary to check whether the object is in phase.
How to send and receive messages over a WebSocket in Java
Aug 16, 2025 am 10:36 AM
Create a WebSocket server endpoint to define the path using @ServerEndpoint, and handle connections, message reception, closing and errors through @OnOpen, @OnMessage, @OnClose and @OnError; 2. Ensure that javax.websocket-api dependencies are introduced during deployment and automatically registered by the container; 3. The Java client obtains WebSocketContainer through the ContainerProvider, calls connectToServer to connect to the server, and receives messages using @ClientEndpoint annotation class; 4. Use the Session getBasicRe
Correct posture for handling non-UTF-8 request encoding in Spring Boot application
Aug 15, 2025 pm 12:30 PM
This article discusses the mechanism and common misunderstandings of Spring Boot applications for handling non-UTF-8 request encoding. The core lies in understanding the importance of the charset parameter in the HTTP Content-Type header, as well as the default character set processing flow of Spring Boot. By analyzing the garbled code caused by wrong testing methods, the article guides readers how to correctly simulate and test requests for different encodings, and explains that Spring Boot usually does not require complex configurations to achieve compatibility under the premise that the client correctly declares encoding.
Exploring Common Java Design Patterns with Examples
Aug 17, 2025 am 11:54 AM
The Java design pattern is a reusable solution to common software design problems. 1. The Singleton mode ensures that there is only one instance of a class, which is suitable for database connection pooling or configuration management; 2. The Factory mode decouples object creation, and objects such as payment methods are generated through factory classes; 3. The Observer mode automatically notifies dependent objects, suitable for event-driven systems such as weather updates; 4. The dynamic switching algorithm of Strategy mode such as sorting strategies improves code flexibility. These patterns improve code maintainability and scalability but should avoid overuse.


