Android平台上利用opencv进行图像的缩放

package cn.netava.opencv;

import java.io.File;

import org.opencv.core.CvType;
import org.opencv.core.Mat;
import org.opencv.core.Size;
import org.opencv.highgui.Highgui;
import org.opencv.imgproc.Imgproc;

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;

public class ButtonSizeImage extends Activity {

private Button deal_button;
private ImageView imgview;
private Bitmap bm;
private boolean flag=false;//判断缩放还是恢复，初始值为false

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// 缩放按钮
deal_button = (Button) this.findViewById(R.id.button1);
// 存放照片图层
imgview = (ImageView) this.findViewById(R.id.imageView1);
// 显示照片
bm = BitmapFactory.decodeFile("/sdcard/girl.jpg");
imgview.setImageBitmap(bm);

//匿名内部类，创建缩小事件监听器
OnClickListener clicklisten=new OnClickListener(){

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if(flag){
deal_button.setText("缩小");
flag=false;
// 显示照片
bm = BitmapFactory.decodeFile("/sdcard/girl.jpg");
imgview.setImageBitmap(bm);
}
else{
deal_button.setText("恢复");
flag=true;
double scale = 0.1; // 缩放比例
Mat img = Highgui.imread("/sdcard/girl.jpg");// 读入图片，将其转换为Mat
Size dsize = new Size(img.width() * scale, img.height() * scale); // 设置新图片的大小
Mat img2 = new Mat(dsize, CvType.CV_16S);// 创建一个新的Mat（opencv的矩阵数据类型）
Imgproc.resize(img, img2,dsize);//调用Imgproc的Resize方法，进行图片缩放
if(Highgui.imwrite("/sdcard/girlnew.jpg", img2)){//将图形保存到new.jpg中
File f = new File("/sdcard/girlnew.jpg");
if(f.exists())
{
bm=BitmapFactory.decodeFile("/sdcard/girlnew.jpg");
imgview.setImageBitmap(bm);

}
}
else{
Toast.makeText(ButtonSizeImage.this, "===========图片缩小失败============！！", 3).show();
}
}
}

};
//缩放按钮添加点击事件监听器
deal_button.setOnClickListener(clicklisten);

}
}