Android实现简单图片压缩的方法

FrameLayout fr=(FrameLayout)findViewById(R.id.FrameLayout01);
BitmapFactory.Options options =new BitmapFactory.Options();
options.inJustDecodeBounds =true;
// 获取这个图片的宽和高
Bitmap bitmap =BitmapFactory.decodeFile("/sdcard/test.jpg", options); //此时返回bm为空
options.inJustDecodeBounds =false;
 //计算缩放比
int be = (int)(options.outHeight/ (float)200);
if (be <= 0)
  be = 1;
options.inSampleSize = be;
//重新读入图片，注意这次要把options.inJustDecodeBounds 设为 false哦
bitmap=BitmapFactory.decodeFile("/sdcard/test.jpg",options);
int w = bitmap.getWidth();
int h = bitmap.getHeight();
System.out.println(w+"  "+h);
ImageView iv=new ImageView(this);
iv.setImageBitmap(bitmap);

File file=new File("/sdcard/feng.png");
try {
  FileOutputStream out=newFileOutputStream(file);
  if(bitmap.compress(Bitmap.CompressFormat.PNG, 100, out)){
    out.flush();
    out.close();
  }
} catch (FileNotFoundException e){
  // TODO Auto-generated catchblock
  e.printStackTrace();
} catch (IOException e) {
  // TODO Auto-generated catchblock
  e.printStackTrace();
}