Android FaceDetector not finding any faces...findFace() returns 0 every time

Question

I am trying to build an app that can detect the number of faces in a picture taken by the devices camera. So far, the code I have is shown below. From researching the question on here, I think it may be an issue with the picture's resolution being too poor for the FaceDetector, but if that is the case, I am not sure how to fix that problem. If that's not the case, then I'm at a loss at what is wrong. Any help is much appreciated!

public class CrowdDetection extends Activity {

ImageView display;
ImageView pic;
Bitmap image;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_crowd_detection);

    display = (ImageView) findViewById(R.id.imageView2);

    Button takePicture = (Button) findViewById(R.id.button1);
    takePicture.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {

            Intent intent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
            startActivityForResult(intent, 0);

        }
    });
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data){

    super.onActivityResult(requestCode, resultCode, data);

    setContentView(R.layout.detect_faces);

    pic = (ImageView) findViewById(R.id.imageView1);

    image = (Bitmap) data.getExtras().get("data");
    image = BitmapFactory.decodeFile(data.getData().getPath());
    pic.setImageBitmap(image);

    Button detect = (Button) findViewById(R.id.button2);
    detect.setOnClickListener(new OnClickListener(){

        @Override
        public void onClick(View v){
            detectFaces();
        }
    });     
}

private void detectFaces() {

    setContentView(R.layout.display_crowd);

    int h = image.getHeight();
    int w = image.getWidth();
    int max = 10;

    FaceDetector detector = new FaceDetector(w, h, max);
    Face[] faces = new Face[max];

    ImageView pic2 = (ImageView) findViewById(R.id.imageView3);
    pic2.setImageBitmap(image);

    int facesFound = detector.findFaces(image, faces);

    TextView result = (TextView) findViewById(R.id.textView3);

    if(facesFound>5){
        result.setText("There are " + facesFound + " faces in this picture, therefore you have a crowd!");
    }
    else{
        result.setText("There are only " + facesFound + " faces in this picture, therefore you do not have a crowd!");
    }

}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.crowd_detection, menu);
    return true;
}

}

Thanks for the help in advance!

score 22 · Accepted Answer · edited Mar 13 '15 at 03:44

22

The reason you can't detect any faces is you need to convert your bitmap to RGB 565.

Use this to convert your bitmap to RGB 565

BitmapFactory.Options bitmapFatoryOptions=new BitmapFactory.Options();
bitmapFatoryOptions.inPreferredConfig=Bitmap.Config.RGB_565;
image=BitmapFactory.decodeResource(getResources(),        R.drawable.image,bitmapFatoryOptions);

edited Mar 13 '15 at 03:44

user229044

232,980
40
330
338

answered Nov 05 '13 at 06:40

Sandeep R

2,284
3
25
51

1

That is very technical answer. Thanks – Murtaza Khursheed Hussain Oct 15 '14 at 07:17
Thus we can only get bitmap from resource folder not from sdCard or internal memory of device. – Amrit Chakradhari Aug 09 '18 at 13:32
There is a way to get image from SD card and create a Bitmap from it. You can check answers from this thread (https://stackoverflow.com/questions/8710515/reading-an-image-file-into-bitmap-from-sdcard-why-am-i-getting-a-nullpointerexc) – Sandeep R Aug 10 '18 at 10:30

Android FaceDetector not finding any faces...findFace() returns 0 every time

1 Answers1