Android人臉檢測類FaceDetector

根據文檔描述，輸入圖片必須爲Bitmap RGB565格式。

人臉的檢測方法是用雙眼來檢測人臉的位置，也就是說無法檢測到嘴、側臉等，雙眼必須同時可見，並且眼鏡會影響檢測的效果。

實際上，FaceDetector檢測到的並不是人的全臉，而只是雙眼。

實際測試中，發現圖片太小的話檢測不到人臉，試驗中使用小於100x100的圖片檢測不到人臉，但是由於Android內存有限，圖片太大的話，會出現無法加載圖片的異常。

檢測到的人臉存放到FaceDetector.Face類中，該類無法再擴展。從該類可以獲取到人眼的中心位置和雙眼之間的具體。

package name.feisky.face; import android.app.Activity;import android.content.Context;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.graphics.PointF;import android.media.FaceDetector;import android.media.FaceDetector.Face;import android.os.Bundle;import android.view.View; public class AndroidFaceDetector extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(new myView(this)); } private class myView extends View{ private int imageWidth, imageHeight; private int numberOfFace = 5; private FaceDetector myFaceDetect; private FaceDetector.Face[] myFace; float myEyesDistance; int numberOfFaceDetected; Bitmap myBitmap; public myView(Context context) { super(context); BitmapFactory.Options BitmapFactoryOptionsbfo = new BitmapFactory.Options(); BitmapFactoryOptionsbfo.inPreferredConfig = Bitmap.Config.RGB_565; myBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.pp, BitmapFactoryOptionsbfo); imageWidth = myBitmap.getWidth(); imageHeight = myBitmap.getHeight(); myFace = new FaceDetector.Face[numberOfFace]; myFaceDetect = new FaceDetector(imageWidth, imageHeight, numberOfFace); numberOfFaceDetected = myFaceDetect.findFaces(myBitmap, myFace); } protected void onDraw(Canvas canvas) { // TODO Auto-generated method stub canvas.drawBitmap(myBitmap, 0, 0, null); Paint myPaint = new Paint(); myPaint.setColor(Color.GREEN); myPaint.setStyle(Paint.Style.STROKE); myPaint.setStrokeWidth(3); for(int i=0; i < numberOfFaceDetected; i++) { Face face = myFace[i]; PointF myMidPoint = new PointF(); face.getMidPoint(myMidPoint); myEyesDistance = face.eyesDistance(); canvas.drawRect( (int)(myMidPoint.x - myEyesDistance), (int)(myMidPoint.y - myEyesDistance), (int)(myMidPoint.x + myEyesDistance), (int)(myMidPoint.y + myEyesDistance), myPaint); } } }}