Java Opencv读取图片并显示

本篇博客介绍如何在Java中使用Opencv实现对图片的读取和显示。

首先是显示部分：

import java.awt.Component;
import java.awt.EventQueue;
import java.awt.image.BufferedImage;

import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;

import org.opencv.core.Core;
import org.opencv.core.Mat;
import org.opencv.imgcodecs.Imgcodecs;
  
  
public class ShowImage {  

    private JFrame frame;  
  
  
    /** 
     * Create the application. 
     */  
    public ShowImage(Mat mat) {  
        initialize(mat);  
    }  
  
    public JFrame getFrame() {
		return frame;
	}
    /** 
     * Initialize the contents of the frame. 
     */  
    private void initialize(Mat mat) {  
        frame = new JFrame();  
        frame.setBounds(20, 100, mat.width()+100, mat.height()+80);  
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);  
        frame.getContentPane().setLayout(null);           
        BufferedImage image=new MatToBufImg(mat, ".png").getImage();  
        JLabel label = new JLabel(""){
        	@Override
        	public void setLabelFor(Component c) {
        		// TODO Auto-generated method stub
        		super.setLabelFor(c);
        	}
        };  
        label.setBounds(0, 0, mat.width(), mat.height());
        frame.getContentPane().add(label);  
        label.setIcon(new ImageIcon(image));  
    }  
  
}  

将Mat类型的图片转化为BufferedImage类型：

import java.awt.image.BufferedImage;
import java.io.ByteArrayInputStream;
import java.io.InputStream;
import javax.imageio.ImageIO;
import org.opencv.core.Mat;
import org.opencv.core.MatOfByte;
import org.opencv.imgcodecs.Imgcodecs;


public class MatToBufImg {
        Mat matrix;
        MatOfByte mob;
        String fileExten;

        // The file extension string should be ".jpg", ".png", etc
        public MatToBufImg(Mat amatrix, String fileExtension) {
                matrix = amatrix;
                fileExten = fileExtension;
                mob = new MatOfByte();
        }

        public BufferedImage getImage() {
                // convert the matrix into a matrix of bytes appropriate for
                // this file extension
        		Imgcodecs.imencode(fileExten, matrix, mob);
                // convert the "matrix of bytes" into a byte array
                byte[] byteArray = mob.toArray();
                BufferedImage bufImage = null;
                try {
                        InputStream in = new ByteArrayInputStream(byteArray);
                        bufImage = ImageIO.read(in);
                } catch (Exception e) {
                        e.printStackTrace();
                }
                return bufImage;
        }
}

主类：

import org.opencv.core.Core;
import org.opencv.core.CvType;
import org.opencv.core.Mat;
import org.opencv.imgcodecs.Imgcodecs;
public class Main{  
  
    public static void main(String[] args) {
       System.loadLibrary(Core.NATIVE_LIBRARY_NAME); 
       String originalImgPath = "img/1.png";
       Mat mat = Imgcodecs.imread(originalImgPath);
       ShowImage window = new ShowImage(mat);  
       window.getFrame().setVisible(true);
    }    
  
}