how to crop the detected face image in opencv java

Question

I detected the face in the image using opencv 2.4.10 in java

I put my face detection code.

import org.opencv.core.Core;
import org.opencv.core.Mat;
import org.opencv.core.MatOfRect;
import org.opencv.core.Point;
import org.opencv.core.Rect;
import org.opencv.core.Scalar;
import org.opencv.core.Size;
import org.opencv.highgui.Highgui;
import org.opencv.imgproc.Imgproc;
import org.opencv.objdetect.CascadeClassifier;

public class FaceDetector {

public static void main(String[] args)throws Exception {
    int x,y,height,width;

    System.loadLibrary(Core.NATIVE_LIBRARY_NAME);
    System.out.println("\nRunning FaceDetector");

    //CascadeClassifier faceDetector = new CascadeClassifier(FaceDetector.class.getResource("haarcascade_frontalface_alt.xml").getPath());
    CascadeClassifier faceDetector=new CascadeClassifier();
    faceDetector.load("C:/opencv-2.4.10/opencv/sources/data/haarcascades/haarcascade_frontalface_alt.xml");
    //System.out.println(""+faceDetector);
   // Mat image = Highgui .imread(FaceDetector.class.getResource("D:/shekar.jpg").getPath());
    Mat image = Highgui .imread("D:/Eclipse - New Juno/New Juno Projects/detectface/man1.jpg");
    MatOfRect faceDetections = new MatOfRect();
    faceDetector.detectMultiScale(image, faceDetections);

    System.out.println(String.format("Detected %s faces", faceDetections.toArray().length));

    for (Rect rect : faceDetections.toArray()) {
        Core.rectangle(image, new Point(rect.x, rect.y), new Point(rect.x + rect.width, rect.y + rect.height),
                new Scalar(0, 255, 0));
    }
    String filename = "china.jpg";
    System.out.println(String.format("Writing %s", filename));
    Highgui.imwrite(filename, image);


}

}

Now i want to crop the detected face and save it as new jpg image in opencv java.

Crop code is

 Rect rectCrop = new Rect(x, y, width, height);
 Mat image_roi = image(rectCrop);
        image_roi.copyTo(cropimage);
        imwrite("cropimage.jpg",image_roi);

The error is

The method image(Rect) is undefined for the type FaceDetector The method imwrite(String, Mat) is undefined for the type FaceDetector

Please anyone help me to solve this.

Thanks

Answer 1

how to crop multiple faces? dhvani.

for (Rect rect : face_Detections.toArray()) {
    Core.rectangle(
        image,
        new Point(rect.x, rect.y),
        new Point(rect.x + rect.width, rect.y + rect.height),
        new Scalar(0, 255, 0));
    rectCrop = new Rect(rect.x, rect.y, rect.width, rect.height);
}

Mat image_roi = new Mat(image,rectCrop);
    Highgui.imwrite("C:\\cropimage_912.jpg",image_roi);
}}