Android Face检测仅适用于不使用SD卡图像的drawable

时间:2012-03-11 15:15:49

标签: android

所以我有代码在任何给定的图像文件中检测多达10个面孔并返回给我信息,如眼睛的位置和其他类似的东西。因此,当我告诉它使用存储在我的项目的资源的drawable文件夹中的图像文件时,它工作得很好。但是,当我有它尝试从我从SD卡导入的位图找到面孔时,它不会找到任何面孔。但这些都是完全相同的图像。有任何想法吗?我的代码如下:

编辑: 经过进一步检查后,我发现当我插入这行代码时System.out.println("Row Bytes: " + sourceImage.getRowBytes()); 我得到的drawable是352和SD卡图像是704.我认为这意味着drawable在.apk文件中被压缩,但SD卡图像显然不是。不确定这是否会影响任何事情。

 public class FaceView extends View {
           private static final int NUM_FACES = 10; // max is 64
           private static final boolean DEBUG = true;

           private FaceDetector arrayFaces;
           private FaceDetector.Face getAllFaces[] = new FaceDetector.Face[NUM_FACES];
           private FaceDetector.Face getFace = null;

           private PointF eyesMidPts[] = new PointF[NUM_FACES];
           private float  eyesDistance[] = new float[NUM_FACES];

           private Bitmap sourceImage;

           private Paint tmpPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
           private Paint pOuterBullsEye = new Paint(Paint.ANTI_ALIAS_FLAG);
           private Paint pInnerBullsEye = new Paint(Paint.ANTI_ALIAS_FLAG);

           private int picWidth, picHeight;
           private float xRatio, yRatio;

           public FaceView(Context context) {
                   super(context);

                   pInnerBullsEye.setStyle(Paint.Style.FILL);
                   pInnerBullsEye.setColor(Color.RED);

                   pOuterBullsEye.setStyle(Paint.Style.STROKE);
                   pOuterBullsEye.setColor(Color.RED);

                   tmpPaint.setStyle(Paint.Style.STROKE);
                   tmpPaint.setTextAlign(Paint.Align.CENTER);

                   BitmapFactory.Options bfo = new BitmapFactory.Options();
                   bfo.inPreferredConfig = Bitmap.Config.RGB_565;

                   //********This code imports the image from the SD card which does not work
                   String imageInSD = Environment.getExternalStorageDirectory()
                        .getAbsolutePath() + "/testfolder/" + "face1" + ".png";

                   Bitmap sourceImage = BitmapFactory.decodeFile(imageInSD,bfo);

                   //**********This code uses an image in the projects drawable folder, this code works.
                   sourceImage = BitmapFactory.decodeResource( getResources() ,R.drawable.face1, bfo);

                   picWidth = sourceImage.getWidth();
                   picHeight = sourceImage.getHeight();

                   arrayFaces = new FaceDetector( picWidth, picHeight, NUM_FACES );
                   arrayFaces.findFaces(sourceImage, getAllFaces);

                   for (int i = 0; i < getAllFaces.length; i++)
                   {
                           getFace = getAllFaces[i];
                           try {
                                   PointF eyesMP = new PointF();
                                   getFace.getMidPoint(eyesMP);
                                   eyesDistance[i] = getFace.eyesDistance();
                                   eyesMidPts[i] = eyesMP;

                                   if (DEBUG)
                                   {
                                           Log.i("Face",
                                                   i +  " " + getFace.confidence() + " " + getFace.eyesDistance() + " "
                                                   + "Pose: ("+ getFace.pose(FaceDetector.Face.EULER_X) + ","
                                                   + getFace.pose(FaceDetector.Face.EULER_Y) + ","
                                                   + getFace.pose(FaceDetector.Face.EULER_Z) + ")"
                                                   + "Eyes Midpoint: ("+eyesMidPts[i].x + "," + eyesMidPts[i].y +")"
                                           );
                                   }
                           }
                           catch (Exception e)
                           {
                                   if (DEBUG) Log.e("Face", i + " is null");
                           }

                   }


           }

           @Override
           protected void onDraw(Canvas canvas)
           {
                   xRatio = getWidth()*1.0f / picWidth;
                   yRatio = getHeight()*1.0f / picHeight;
                   canvas.drawBitmap( sourceImage, null , new Rect(0,0,getWidth(),getHeight()),tmpPaint);
                   for (int i = 0; i < eyesMidPts.length; i++)
                   {
                           if (eyesMidPts[i] != null)
                           {
                                   pOuterBullsEye.setStrokeWidth(eyesDistance[i] /6);
                                   canvas.drawCircle(eyesMidPts[i].x*xRatio, eyesMidPts[i].y*yRatio, eyesDistance[i] / 2 , pOuterBullsEye);
                                   canvas.drawCircle(eyesMidPts[i].x*xRatio, eyesMidPts[i].y*yRatio, eyesDistance[i] / 6 , pInnerBullsEye);
                           }
                   }


           }  

}

2 个答案:

答案 0 :(得分:5)

好吧我相信我知道你的问题在这里。设备无法将图像渲染为位图图像,因为它位于外部存储器中。面部识别工作只是没有进入画布。所有设备都在我的xoom上具有渲染限制(2048x2048)我发现here。将图像作为资源添加时它​​起作用的原因是因为你的文件缩小了,因为它构建了.apk(说实话我不知道为什么会这样做,但是我留下了一些println用于测试,其他人可以更好地回答这个问题。无论如何,我只是在你的代码寻找面之后,在它尝试将位图渲染到画布之前,除以2来缩放位图。现在一切似乎都很好。您可能需要调整面部指示器但功能正常。我希望这会有所帮助。

public class FaceView extends View {
private static final int NUM_FACES = 1; // max is 64
private static final boolean DEBUG = true;

private FaceDetector arrayFaces;
private FaceDetector.Face getAllFaces[] = new FaceDetector.Face[NUM_FACES];
private FaceDetector.Face getFace = null;

private PointF eyesMidPts[] = new PointF[NUM_FACES];
private float  eyesDistance[] = new float[NUM_FACES];

private Bitmap sourceImage;

private Paint tmpPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
private Paint pOuterBullsEye = new Paint(Paint.ANTI_ALIAS_FLAG);
private Paint pInnerBullsEye = new Paint(Paint.ANTI_ALIAS_FLAG);

private int picWidth, picHeight;
private float xRatio, yRatio;

public FaceView(Context context) {
        super(context);

        pInnerBullsEye.setStyle(Paint.Style.FILL);
        pInnerBullsEye.setColor(Color.RED);

        pOuterBullsEye.setStyle(Paint.Style.STROKE);
        pOuterBullsEye.setColor(Color.RED);

        tmpPaint.setStyle(Paint.Style.STROKE);
        tmpPaint.setTextAlign(Paint.Align.CENTER);

        BitmapFactory.Options bfo = new BitmapFactory.Options();
        bfo.inPreferredConfig = Bitmap.Config.RGB_565;

        //********This code imports the image from the SD card which does not work
        String imageInSD = Environment.getExternalStorageDirectory().getAbsolutePath() + "/face1" + ".jpg";

        System.out.println(imageInSD);

        sourceImage = BitmapFactory.decodeFile(imageInSD, bfo);

        //Bitmap sourceImage;// = BitmapFactory.decodeFile(imageInSD,bfo);


        //**********This code uses an image in the projects drawable folder, this code works.
        //sourceImage = BitmapFactory.decodeResource( getResources() ,R.drawable.face1, bfo);

        picWidth = sourceImage.getWidth();
        picHeight = sourceImage.getHeight(); 

        System.out.println(picWidth + "x" + picHeight);

        arrayFaces = new FaceDetector( picWidth, picHeight, NUM_FACES );
        arrayFaces.findFaces(sourceImage, getAllFaces);

        sourceImage = Bitmap.createScaledBitmap (sourceImage, picWidth/2, picHeight/2, false);

        for (int i = 0; i < getAllFaces.length; i++)
        {
                getFace = getAllFaces[i];
                try {
                        PointF eyesMP = new PointF();
                        getFace.getMidPoint(eyesMP);
                        eyesDistance[i] = getFace.eyesDistance();
                        eyesMidPts[i] = eyesMP;

                        if (DEBUG)
                        {
                                Log.i("Face",
                                        i +  " " + getFace.confidence() + " " + getFace.eyesDistance() + " "
                                        + "Pose: ("+ getFace.pose(FaceDetector.Face.EULER_X) + ","
                                        + getFace.pose(FaceDetector.Face.EULER_Y) + ","
                                        + getFace.pose(FaceDetector.Face.EULER_Z) + ")"
                                        + "Eyes Midpoint: ("+eyesMidPts[i].x + "," + eyesMidPts[i].y +")"
                                );
                        }
                }
                catch (Exception e)
                {
                        if (DEBUG) Log.e("Face", i + " is null");
                }

        }


}

@Override
protected void onDraw(Canvas canvas)
{
        xRatio = getWidth()*1.0f / picWidth; 
        yRatio = getHeight()*1.0f / picHeight;
        canvas.drawBitmap( sourceImage, null , new Rect(0,0,getWidth(),getHeight()),tmpPaint);
        for (int i = 0; i < eyesMidPts.length; i++)
        {
                if (eyesMidPts[i] != null)
                {
                        pOuterBullsEye.setStrokeWidth(eyesDistance[i] /6);
                        canvas.drawCircle(eyesMidPts[i].x*xRatio, eyesMidPts[i].y*yRatio, eyesDistance[i] / 2 , pOuterBullsEye);
                        canvas.drawCircle(eyesMidPts[i].x*xRatio, eyesMidPts[i].y*yRatio, eyesDistance[i] / 6 , pInnerBullsEye);
                }
        }


}

}

答案 1 :(得分:5)

原来问题是相机拍摄的照片会保存为PNG文件,如果使用JPG文件,只能从SD卡成功进行人脸检测。只需将文件转换为JPG即可正常工作。