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I need to detect the user face and also compare the face to authenticate my application,for that I used FaceDetector API to detect the user face.

When i run my code it works without any defects.But it gives detected faces count as Zero.

    public class AndroidFaceDetectorActivity extends Activity {
    private static final int TAKE_PICTURE_CODE = 100;
    private static final int MAX_FACES = 5;

    private Bitmap cameraBitmap = null;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        ((Button)findViewById(R.id.take_picture)).setOnClickListener(btnClick);
    }

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

            if(TAKE_PICTURE_CODE == requestCode){
                    processCameraImage(data);
            }
    }


    private void openCamera(){
        Intent intent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);

        startActivityForResult(intent, TAKE_PICTURE_CODE);
    }

    private void processCameraImage(Intent intent){
        setContentView(R.layout.detectlayout);

        ((Button)findViewById(R.id.detect_face)).setOnClickListener(btnClick);

        ImageView imageView = (ImageView)findViewById(R.id.image_view);

        cameraBitmap = (Bitmap)intent.getExtras().get("data");

        imageView.setImageBitmap(cameraBitmap);
    }

    private void detectFaces(){
        if(null != cameraBitmap){
                Log.d("FACE_RECOGNITION","CHECK");
                int width = cameraBitmap.getWidth();
                int height = cameraBitmap.getHeight();

                FaceDetector detector = new FaceDetector(width, height,AndroidFaceDetectorActivity.MAX_FACES);
                Face[] faces = new Face[AndroidFaceDetectorActivity.MAX_FACES];

                Bitmap bitmap565 = Bitmap.createBitmap(width, height, Config.RGB_565);
                Paint ditherPaint = new Paint();
                Paint drawPaint = new Paint();

                ditherPaint.setDither(true);
                drawPaint.setColor(Color.RED);
                drawPaint.setStyle(Paint.Style.STROKE);
                drawPaint.setStrokeWidth(2);

                Canvas canvas = new Canvas();
                canvas.setBitmap(bitmap565);
                canvas.drawBitmap(cameraBitmap, 0, 0, ditherPaint);

                int facesFound = detector.findFaces(bitmap565, faces);
                PointF midPoint = new PointF();
                float eyeDistance = 0.0f;
                float confidence = 0.0f;

                Log.i("FaceDetector", "Number of faces found: " + facesFound);

                if(facesFound > 0)
                {
                        for(int index=0; index<facesFound; ++index){
                                faces[index].getMidPoint(midPoint);
                                eyeDistance = faces[index].eyesDistance();
                                confidence = faces[index].confidence();

                                Log.i("FaceDetector", 
                                                "Confidence: " + confidence + 
                                                ", Eye distance: " + eyeDistance + 
                                                ", Mid Point: (" + midPoint.x + ", " + midPoint.y + ")");

                                canvas.drawRect((int)midPoint.x - eyeDistance , 
                                                                (int)midPoint.y - eyeDistance , 
                                                                (int)midPoint.x + eyeDistance, 
                                                                (int)midPoint.y + eyeDistance, drawPaint);
                        }
                }

                String filepath = Environment.getExternalStorageDirectory() + "/facedetect" + System.currentTimeMillis() + ".jpg";

                    try {
                            FileOutputStream fos = new FileOutputStream(filepath);

                            bitmap565.compress(CompressFormat.JPEG, 90, fos);

                            fos.flush();
                            fos.close();
                    } catch (FileNotFoundException e) {
                            e.printStackTrace();
                    } catch (IOException e) {
                            e.printStackTrace();
                    }

                    ImageView imageView = (ImageView)findViewById(R.id.image_view);

                    imageView.setImageBitmap(bitmap565);
        }
    }

    private View.OnClickListener btnClick = new View.OnClickListener() {
            //@Override
            public void onClick(View v) {
                    switch(v.getId()){
                            case R.id.take_picture:         openCamera();   break;
                            case R.id.detect_face:          detectFaces();  break;  
                    }
            }
    };
}

What i did wrong?

or

Is any other way to do that?

Thanks

4

1 に答える 1

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getExtras().get("data")目的のためMediaStore.ACTION_IMAGE_CAPTUREに、サムネイルとして機能する可能性のある非常に低解像度のビットマップ（160x120ピクセルだと思います）を生成しますが、顔検出がその仕事をするのに十分ではありません.

通常、フォームを受信できる中解像度の画像 (64x480 ピクセルなど) では顔検出は問題ありませんCamera.previewCallback()が、この方法では、アプリでカメラを制御するアクセス許可とコードが必要であり、そのためのインテントを使用することはできません。

Android での顔検出の公式は次のとおりです: http://developer.android.com/guide/topics/media/camera.html#face-detection。

この方法が本当に好きな場合はgetData()、キャプチャした画像をフル解像度で見つけて、次のようにビットマップに変換することができます。

cameraBitmap = BitmapFactory.decodeFile(data.getData().getPath());
于 2012-12-26T10:31:27.777 に答える