image-pool-service/src/main/java/com/mokasz/image_pool/algorithm/OpenCvService.java

package com.mokasz.image_pool.algorithm;

import org.bytedeco.javacpp.Loader;
import org.bytedeco.opencv.opencv_java;
import org.opencv.core.Mat;
import org.opencv.core.MatOfByte;
import org.opencv.img_hash.PHash;
import org.opencv.imgcodecs.Imgcodecs;

public class OpenCvService {
    // 静态初始化 OpenCV
    static {
        Loader.load(opencv_java.class);
    }
    private final PHash pHash = PHash.create();

    private static void transformMatToArrayOfFloat(Mat mat, float[] floats) {
        if (mat.width() != 8 || mat.height() != 1) throw new RuntimeException("Matrix dimension is not 1x8");
        for (int i = 0; i < 8; i++) {
            floats[i] = (float) mat.get(0, i)[0];
        }
    }

    public void calculatePHash (byte[] fileBytes, float[] vector) {
        Mat input = Imgcodecs.imdecode(new MatOfByte(fileBytes), Imgcodecs.IMREAD_UNCHANGED);
        Mat output = new Mat();
        pHash.compute(input, output);
        transformMatToArrayOfFloat(output, vector);
    }
}