public void startPhotoZoom(Uri uri) {

Intent intent = new Intent("com.android.camera.action.CROP");

intent.setDataAndType(uri, "image/*");//类型

intent.putExtra("crop", "true"); 

intent.putExtra("aspectX", 1);

intent.putExtra("aspectY", 1);

intent.putExtra("outputX", 300);

intent.putExtra("outputY", 300);

intent.putExtra("return-data", true);返回的数据 bundle接收

startActivityForResult(intent, 0);

}