Android拍照得到全尺寸图片并进行压缩

<linearlayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:orientation="vertical" >
  <button
    android:id="@+id/take_photo"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="take photo" />
  <button
    android:id="@+id/get_photo"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="get photo" />
  <imageview
    android:id="@+id/picture"
    android:layout_width="300dp"
    android:layout_height="300dp"
    android:layout_gravity="center_horizontal" />
</linearlayout>
package com.example.choosepictest;
import java.io.file;
import java.io.ioexception;
import java.text.simpledateformat;
import java.util.date;
import android.app.activity;
import android.content.intent;
import android.graphics.bitmap;
import android.graphics.bitmapfactory;
import android.net.uri;
import android.os.bundle;
import android.os.environment;
import android.provider.mediastore;
import android.view.view;
import android.view.view.onclicklistener;
import android.widget.button;
import android.widget.imageview;
public class mainactivity extends activity implements onclicklistener {
  static final int request_image_capture = 1;
  private button takephoto;
  private button getphoto;
  private imageview picture;
  private uri imguri;
  @override
  protected void oncreate(bundle savedinstancestate) {
    super.oncreate(savedinstancestate);
    setcontentview(r.layout.activity_main);
    takephoto = (button) findviewbyid(r.id.take_photo);
    getphoto = (button) findviewbyid(r.id.get_photo);
    picture = (imageview) findviewbyid(r.id.picture);
    takephoto.setonclicklistener(this);
    getphoto.setonclicklistener(this);
  }  
  @override
  public void onclick(view v) {
    switch (v.getid()) {
    case r.id.take_photo:
      dispatchtakepictureintent();
      break;
    default:
      break;
    }
  }
  // 保存全尺寸照片
  string mcurrentphotopath;
  private void dispatchtakepictureintent() {
    file appdir = new file(environment.getexternalstoragedirectory(),
        "/etoury/piccache");
    if (!appdir.exists()) {
      appdir.mkdir();
    }
    string timestamp = new simpledateformat("yyyymmdd_hhmmss")
        .format(new date());
    string filename = timestamp + ".jpg";
    file outputimage = new file(appdir, filename);
    try {
      if (outputimage.exists()) {
        outputimage.delete();
      }
      outputimage.createnewfile();
    } catch (ioexception e) {
      e.printstacktrace();
    }
    mcurrentphotopath = outputimage.getabsolutepath();
    imguri = uri.fromfile(outputimage);
    // 意图 相机
    intent intent = new intent("android.media.action.image_capture");
    intent.putextra(mediastore.extra_output, imguri);
    // 如果有相机
    if (intent.resolveactivity(getpackagemanager()) != null) {
      startactivityforresult(intent, request_image_capture);
    }
  }
  //解码缩放图片(decode a scaled image)
  private void setpic() {
    // get the dimensions of the view
    int targetw = picture.getwidth();
    int targeth = picture.getheight();
    // get the dimensions of the bitmap
    bitmapfactory.options bmoptions = new bitmapfactory.options();
    // 该 值设为true那么将不返回实际的bitmap，也不给其分配内存空间这样就避免内存溢出了。但是允许我们查询图片的信息这其中就包括图片大小信息
    bmoptions.injustdecodebounds = true;
    bitmapfactory.decodefile(mcurrentphotopath, bmoptions);
    int photow = bmoptions.outwidth;
    int photoh = bmoptions.outheight;
    // determine how much to scale down the image
    // math.min求最小值
    int scalefactor = math.min(photow/targetw, photoh/targeth);
    // decode the image file into a bitmap sized to fill the view
    bmoptions.injustdecodebounds = false;
    // 设置恰当的insamplesize可以使bitmapfactory分配更少的空间以消除该错误
    bmoptions.insamplesize = scalefactor;
    // 如果inpurgeable设为true的话表示使用bitmapfactory创建的bitmap,用于存储pixel的内存空间在系统内存不足时可以被回收
    bmoptions.inpurgeable = true;
    bitmap bitmap = bitmapfactory.decodefile(mcurrentphotopath, bmoptions);
    picture.setimagebitmap(bitmap);
  }
  @override
  protected void onactivityresult(int requestcode, int resultcode, intent data) {
    if (resultcode == result_ok) {
      switch (requestcode) {
      case request_image_capture:
        setpic();
        break;
      default:
        break;
      }
    }
  }
}