java 识别图像是否是同一个人，贴代码

Java 识别图像是否是同一个人，通常需要使用人脸识别技术。以下是使用 Java 实现的简单示例代码：

import java.awt.Graphics;
import java.awt.Image;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import org.bytedeco.javacpp.Loader;
import org.bytedeco.opencv.global.opencv_core;
import org.bytedeco.opencv.opencv_core.IplImage;
import org.bytedeco.opencv.opencv_core.Mat;
import org.bytedeco.opencv.opencv_face.FaceRecognizer;
import org.bytedeco.opencv.opencv_face.LBPHFaceRecognizer;
import org.bytedeco.opencv.opencv_imgcodecs;

public class FaceRecognition {

    public static void main(String[] args) throws IOException {
        String path = "path/to/images";
        File[] files = new File(path).listFiles();
        BufferedImage[] images = new BufferedImage[files.length];
        for (int i = 0; i < files.length; i++) {
            images[i] = ImageIO.read(files[i]);
        }
        FaceRecognizer recognizer = LBPHFaceRecognizer.create();
        Mat[] mats = new Mat[images.length];
        for (int i = 0; i < images.length; i++) {
            mats[i] = toMat(images[i]);
            recognizer.update(mats[i], i);
        }
        int[] labels = new int[images.length];
        for (int i = 0; i < labels.length; i++) {
            labels[i] = i;
        }
        recognizer.train(mats, labels);
        Mat testMat = toMat(ImageIO.read(new File("path/to/test/image")));
        int[] predictedLabel = new int[1];
        double[] predictedConfidence = new double[1];
        recognizer.predict(testMat, predictedLabel, predictedConfidence);
        if (predictedConfidence[0] < 100) {
            System.out.println("Test image is recognized as " + files[predictedLabel[0]].getName());
        } else {
            System.out.println("Test image is not recognized as any known person.");
        }
    }

    private static Mat toMat(BufferedImage image) {
        IplImage iplImage = Loader.bufferedImageToIplImage(image);
        Mat mat = opencv_core.cvarrToMat(iplImage);
        Mat grayMat = new Mat();
        opencv_imgproc.cvtColor(mat, grayMat, opencv_imgproc.COLOR_BGR2GRAY);
        return grayMat;
    }

}

该示例使用 OpenCV 中的 LBPHFaceRecognizer 类实现人脸识别。首先，将所有训练图像读入内存，并转换为 Mat 对象。然后，使用 FaceRecognizer 的 update() 方法将每个 Mat 对象添加到训练集中。接下来，将所有训练图像的标签传递给 train() 方法进行训练。

最后，将要测试的图像读入内存，并转换为 Mat 对象。使用 FaceRecognizer 的 predict() 方法预测测试图像的标签。如果预测的置信度小于 100，则将测试图像识别为已知人物；否则，将其视为未知人物。