Android人脸检测类FaceDetector

根据文档描述，输入图片必须为Bitmap RGB565格式。
Android人脸的检测方法是用双眼来检测人脸的位置，也就是说无法检测到嘴、侧脸等，双眼必须同时可见，并且眼镜会影响检测的效果。
实际上，FaceDetector检测到的并不是人的全脸，而只是双眼。
实际测试中，发现图片太小的话检测不到人脸，试验中使用小于100x100的图片检测不到人脸，但是由于Android内存有限，图片太大的话，会出现无法加载图片的异常。
检测到的人脸存放到FaceDetector.Face类中，该类无法再扩展。从该类可以获取到人眼的中心位置和双眼之间的具体。  

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);

}

}

}

}