onFaceDetection在运行时只调用一次或两次，但在使用断点进行调试时效果很好

Question

This is the code I am using for face detection, the problem is when I debug this code with android studio the onFaceDetection method is called multiple times and face is detected perfectly(When i put a break point inside the method). But when I run it without any break points the method is called only 2-3 times and face detection doesn't take place. Any help regarding this would be much appreciated, as you can see from the code I've tried stopping and starting face detection.

void setFaceDetectionListener() {
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
        mFaceDetectionListener = new Camera.FaceDetectionListener() {
            Handler faceDetectionHandler;
            @Override
            public void onFaceDetection(final Camera.Face[] faces, final Camera camera) {
                if(faceDetectionHandler == null){//Initialize
                    faceDetectionHandler = new Handler();
                    Toast.makeText(HWTestActivity.this,
                            UiMessages.MSG_SHOW_YOUR_FACE.toString(),
                            Toast.LENGTH_SHORT).show();
                }
                faceDetectionHandler.post(new Runnable() {
                    @Override
                    public void run() {
                        Log.e("faceDetect", "No of faces = " + faces.length);
                        if (!is_face_detected) {
                            Toast.makeText(HWTestActivity.this,
                                    UiMessages.MSG_DETECTING_YOUR_FACE.toString(),
                                    Toast.LENGTH_SHORT).show();
                            is_face_detected = faces.length > 0;
                        }
                        if (faces.length > 0) {
                            Toast.makeText(HWTestActivity.this,
                                    UiMessages.MSG_FACE_DETECTED.toString(),
                                    Toast.LENGTH_SHORT).show();
                            camera.stopFaceDetection();
                        } else {
                            camera.stopFaceDetection();
                            camera.startFaceDetection();
                        }
                    }
                });
            }
        };
    }
}

Answer 1

This was ignorance on my part, apparently you can't have face detection running while the media recorder is running, So guys don't try to run face detection while you are recording with the camera simultaneously.

If you really wanted to detect faces while recording then you should use the

onPreviewFrame(byte[] pixelData, Camera camera)

method in

Camera.PreviewCallback()

convert the pixelData to RGB_565 bitmap and supply it to the FaceDetector.findfaces method. But in my experience I find this method to be very unreliable.