Android - Zoom imagenes

import android.content.Context;

import android.graphics.Canvas;

import android.graphics.drawable.Drawable;

import android.view.KeyEvent;

import android.view.View;

import android.widget.Button;

import android.widget.ImageButton;

public class Zoom extends View {

    private Drawable image;

    ImageButton img,img1;

    private int zoomControler=20;

    public Zoom(Context context){

            super(context);

            image=context.getResources().getDrawable(R.drawable.j);

            //image=context.getResources().getDrawable(R.drawable.icon);

            setFocusable(true);

    }

    @Override

    protected void onDraw(Canvas canvas) {

        super.onDraw(canvas);

        //here u can control the width and height of the images........ this line is very important

        image.setBounds((getWidth()/2)-zoomControler, (getHeight()/2)-zoomControler, (getWidth()/2)+zoomControler, (getHeight()/2)+zoomControler);

        image.draw(canvas);

    }

    @Override

    public boolean onKeyDown(int keyCode, KeyEvent event) {

            if(keyCode==KeyEvent.KEYCODE_DPAD_UP){

                    // zoom in

                    zoomControler+=10;

            }

            if(keyCode==KeyEvent.KEYCODE_DPAD_DOWN){

                    // zoom out

                    zoomControler-=10;

            }

            if(zoomControler<10){

                    zoomControler=10;

            }

            invalidate();

            return true;

    }

}

package Clases;

import javax.swing.JApplet;

public class Principal extends JApplet {

 panelDibujo pd;

 public void init(){

  pd=new panelDibujo();

  add(pd);

 }

}

Clase panelDibujo

package Clases;

import java.awt.*;

import java.awt.event.*;

import javax.swing.ImageIcon;

import javax.swing.JPanel;

public class panelDibujo extends JPanel implements MouseMotionListener,MouseWheelListener{

 ImageIcon imagen;

 int x=0;

 int y=0;

 double zoom=1;

 public panelDibujo(){

  imagen=new ImageIcon(getClass().getResource("../Imagenes/foto.jpg"));

  addMouseMotionListener(this);

  addMouseWheelListener(this);

 }

 public void paintComponent(Graphics g){

  super.paintComponents(g);

  Graphics2D g2d=(Graphics2D)g;

  g2d.scale(zoom, zoom);

  g2d.drawImage(imagen.getImage(), x, y, this);

 }

 @Override

 public void mouseDragged(MouseEvent e) {

 }

 @Override

 public void mouseMoved(MouseEvent e) {

  if(x>-(imagen.getIconWidth()-this.getWidth())){

   if(e.getX()>(this.getWidth()-50)){

    x-=10;

    repaint();

   }

  }

  if(x<0){

   if(e.getX()>0 && e.getX()<50){

    x+=10;

    repaint();

   }

  }

  if(y<0){

   if(e.getY()>0 && e.getY()<50){

    y+=10;

    repaint();

   }

  }

  if(y>-(imagen.getIconHeight()-this.getHeight())){

   if(e.getY()>(this.getHeight()-50)){

    y-=10;

    repaint();

   }

  }

 }

 @Override

 public void mouseWheelMoved(MouseWheelEvent e) {

  if(e.getWheelRotation()<0){

   zoom+=-e.getUnitsToScroll()*0.3;

  }else{

   if(zoom>1){

    zoom-=e.getUnitsToScroll()*0.3;

   }

  }

  repaint();

 }

}