图像叠加/比较和像素颜色变化

Question

我需要比较两个相似图像中的像素，创建保存的第三个图像，其中两个相同的像素变为蓝色。代码还需要在开始比较之前检查图像的大小是否相同，如果大小不同，则会向控制台退出并返回错误。

这是我的代码。我仍然需要覆盖这两个图像并将相似的像素变成蓝色。

我需要使用 Filechooser.pickAFile 但除此之外我完全不知道如何去做。

// Karl Thomas
// kthoma34
// Mon @ 4:00

import java.awt.Color;

public class PP2kthoma34 
{
  
  public static void main (String[] args) 
  {
    // Original picture
    Picture p1;            // create the variable
    String fileName = FileChooser.pickAFile();
    FileChooser.setMediaPath ( fileName );
    System.out.println (fileName);
    p1 = new Picture( fileName );
    
    // Width and length of original picture
    int width1 = p1.getWidth();
    int height1 = p1.getHeight();
    Pixel[] pixelArray1 = p1.getPixels();
    System.out.println(pixelArray1.length + "pixels");
    System.out.println("");
    
    
    
    // Modified picture
    Picture p2;            // create the variable
    String filename2;
    filename2 = FileChooser.pickAFile();
    FileChooser.setMediaPath ( filename2 );
    System.out.println (filename2);
    p2 = new Picture( filename2 );
    
    //Width and Height of manipulated picture
    int width2 = p2.getWidth();
    int height2 = p2.getHeight();
    Pixel[] pixelArray2 = p2.getPixels();
    System.out.println(pixelArray2.length + "pixels");
    System.out.println("");
    
    //checking that the images are the same size
    if ((width1 != width2) || (height1 != height2)) 
     {
      System.err.println("Error: Image dimensions do not match");
      System.exit(1);
     }
    
    // Save Third image with similarities highlighted in blue.
    String filename3;
    filename3 = FileChooser.pickAFile();
    p2.write( filename3 );
  }

}// end 

Answer 1

这应该可以帮助你：(Java loop through pixels in an image)

这是一个关于使用 BufferedImage 循环图像的已回答线程，因此您应该能够在 Java API 中找到大量的解释（关于使用和功能）

在已回答的主题中，它还展示了如何将图像的像素设置为特定颜色。

请记住，所有关于该线程着色的内容都应该定制以满足您的需求。

即您必须首先创建具有正确测量值的第三张图片（再次使用 BufferedImage），然后检查两张图片中所选像素的颜色，如果它们匹配，则第三张图片将相同的像素设置为蓝色，如果没有，你就按照你的想法去做。

如果您需要更多细节，请直接说出来，我会看看能为您做些什么。

编辑：(16.03.2015)

以下是一个工人阶级，可以完全按照您的意愿行事。我试图尽可能清楚地评论所有内容，但根据经验，我知道这对其他人来说并不总是足够清楚。随意以任何您想要的方式使用此代码。

快速免责声明：您必须将包名称更改为您自己的包，并且需要在您的 main.class 中创建此类的对象。在主类中尽可能少地编码总是更漂亮、更高效。

比较类

    package stackexchange;

import java.awt.Color;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;

import javax.imageio.ImageIO;

public class PictureOverlayTest {
    /*
     * Four variables, three for the wanted BufferedImages, one String for the
     * Path of the third Image, which does not already exist.
     */

    private BufferedImage image1;
    private BufferedImage image2;
    private BufferedImage image3;

    private String pathImage3;

    public PictureOverlayTest(String filePathAndName1, String filePathAndName2,
            String filePathAndName3) throws IOException {
        /*
         * Constructor in order to keep this method reusable and clean. Needs
         * three Strings. The paths and Filenames of all three images. Image 1
         * and 2 should exist already, Image 3 will be created if all
         * requirements are met. Constructor creates the first two buffered
         * images, sets all needed variables and starts the checkAndCompare()
         * method
         */

        File file = new File(filePathAndName1);
        this.image1 = ImageIO.read(file);

        file = new File(filePathAndName2);
        this.image2 = ImageIO.read(file);

        this.pathImage3 = filePathAndName3;
        checkAndCompare();
    }

    private void checkAndCompare() throws IOException {
        /*
         * This function creates the Color blue, compares the sizes of both
         * pictures and if they are the same, creates a third image. Then it
         * loops through the two images and compares each pixel. If the pixels
         * are the same, the third image gets a blue pixel at that point
         */

        Color blue = Color.blue;

        if (image1.getHeight() == image2.getHeight()
                && image1.getWidth() == image2.getWidth()) {

            image3 = new BufferedImage(image1.getWidth(), image1.getHeight(),
                    image1.getType());
            for (int y = 0; y < image1.getHeight(); y++) {
                for (int x = 0; x < image1.getWidth(); x++) {

                    int colorImage1 = image1.getRGB(x, y);
                    int colorImage2 = image2.getRGB(x, y);

                    if (colorImage1 == colorImage2) {

                        image3.setRGB(x, y, blue.getRGB());

                    } else {

                        // Whatever Color you want. By default it is black.

                    }

                }
            }
            savePicture3();
            System.out.println("Message: Image comparison is done");

        } else {

            System.out.println("Error: Image dimensions do not match");

        }

    }

    private void savePicture3() throws IOException {
        /*
         * This method saves the created Image into a file onto your computer.
         * The if() statement is used to check if the file was successfully
         * created, in order to avoid unwanted errors. Keep in mind, that you
         * have to change the "bmp" in ImageIO.write() to whatever format you
         * actually want
         */

        File file = new File(pathImage3);
        if (file.createNewFile()) {
            ImageIO.write(image3, "bmp", file);
        }
    }

}

主类

package stackexchange;

import java.io.IOException;

public class Main {

    public static void main(String[] args) {
        // TODO Auto-generated method stub

        try {
            PictureOverlayTest test = new PictureOverlayTest(
                    "H:\\stackexchange\\file1.bmp",
                    "H:\\stackexchange\\file2.bmp",
                    "H:\\stackexchange\\file3.bmp");
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

}