从位图android实现人脸检测答案

【问题标题】：Implementing Face Detection from bitmap android从位图android实现人脸检测
【发布时间】：2014-01-20 23:49:42
【问题描述】：

人脸检测

我有一个位图想从 java 中的位图中检测人脸。任何人都有想法从图像中获取面子。

【问题讨论】：

【解决方案1】：

您可以使用以下代码获取人脸位图

private Bitmap cropBitmap1(Bitmap bmp2, Face face) {

        Matrix mat = new Matrix();
        int x = (int) face.getPosition().x/2;
        int y = (int) face.getPosition().y/2;
        int width = (int) face.getWidth() / 2;
        int height = (int) face.getHeight() / 2;

        Bitmap bmOverlay = Bitmap.createBitmap(bmp2, x , y,width,height,mat,true);
        return bmOverlay;
    }

【讨论】：

【解决方案2】：

您可以尝试使用此代码在位图图像中检测到的每个人脸周围绘制一个矩形。

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 FaceDetection extends Activity {

 @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.jennifer_lopez, BitmapFactoryOptionsbfo);
   imageWidth = myBitmap.getWidth();
   imageHeight = myBitmap.getHeight();
   myFace = new FaceDetector.Face[numberOfFace];
   myFaceDetect = new FaceDetector(imageWidth, imageHeight,
     numberOfFace);
   numberOfFaceDetected = myFaceDetect.findFaces(myBitmap, myFace);

  }

  @Override
  protected void onDraw(Canvas canvas) {

   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 * 2),
      (int) (myMidPoint.y - myEyesDistance * 2),
      (int) (myMidPoint.x + myEyesDistance * 2),
      (int) (myMidPoint.y + myEyesDistance * 2), myPaint);
   }
  }
 }

}

【讨论】：

这种方法的可行性有多大？

【解决方案3】：

您在 Android SDK 中对此提供了支持。你应该检查this

【讨论】：