Android调用系统相机拍照保存照片很小解决方案

保存图片小的一般操作步骤：

1. 调用系统相机

Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(intent, 1); 

2. 保存照片

@Override
 protected void onActivityResult(int requestCode, int resultCode, Intent data) {
  // TODO Auto-generated method stub
  super.onActivityResult(requestCode, resultCode, data);
  System.out.println("onActivityResult start");
  
  if (resultCode == Activity.RESULT_OK) {
   System.out.println("enter");
        String sdStatus = Environment.getExternalStorageState();  
        if (!sdStatus.equals(Environment.MEDIA_MOUNTED)) { // 检测sd是否可用  
            Log.i("TestFile",  
                    "SD card is not avaiable/writeable right now."); 
            System.out.println("SD card is not avaiable/writeable right now.");
            return;  
        }  
        String name = System.currentTimeMillis() + ".jpg";;     
        //Toast.makeText(this, name, Toast.LENGTH_LONG).show();  
        Bundle bundle = data.getExtras();  
        Bitmap bitmap = (Bitmap) bundle.get("data");// 获取相机返回的数据，并转换为Bitmap图片格式  
      
        FileOutputStream b = null;  
        File file = new File("/mnt/sdcard/DCIM/Camera/");  
        file.mkdirs();// 创建文件夹  
        System.out.println("mkdirs");
        String fileName = "/mnt/sdcard/DCIM/Camera/"+name;  
  
            try {  
                b = new FileOutputStream(fileName);  
                bitmap.compress(Bitmap.CompressFormat.JPEG, 100, b);// 把数据写入文件  
        } catch (FileNotFoundException e) {  
            e.printStackTrace();
        } finally {  
            try {  
                b.flush();  
                b.close();  
            } catch (IOException e) {  
                e.printStackTrace();
            }  
        }  
 

小图片的造成的原因，从返回值中取照片的数据是已经被压缩了，要想不被压缩我们可以在调用系统相机时指定照片的保存位置

 private String camera_path = Environment.getExternalStorageDirectory().toString() + "/Photo_LJ/";//照片保存位置

 private String camera_photo_name;// 保存的名称

Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);

        File path1 = new File(camera_path);

        if (!path1.exists()) {

            path1.mkdirs();

        }

        camera_photo_name = System.currentTimeMillis() + ".jpg";

        File file = new File(path1, camera_photo_name);

        // mOutPutFileUri = Uri.fromFile(file);

        intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(file));

        startActivityForResult(intent, 1);

重载方法

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        switch (requestCode) {
        case TAKE_PICTURE:
            if (resultCode == RESULT_OK) 
                String filename = camera_path + "/" + camera_photo_name;
                Bitmap bm = compressImageFromFile(filename);

                ImageItem takePhoto = new ImageItem();
                takePhoto.setBitmap(bm);
                Bimp.tempSelectBitmap.add(takePhoto);
            }
            break;
        }

照片很大，要显示出来我们最好对它进行一下压缩

private Bitmap compressImageFromFile(String srcPath) {
        BitmapFactory.Options newOpts = new BitmapFactory.Options();
        newOpts.inJustDecodeBounds = false;// 只读边,不读内容
        Bitmap bitmap = BitmapFactory.decodeFile(srcPath, null);

        newOpts.inJustDecodeBounds = false;
        int w = newOpts.outWidth;
        int h = newOpts.outHeight;
        float hh = 800f;//
        float ww = 480f;//
        int be = 1;
        if (w > h && w > ww) {
            be = (int) (newOpts.outWidth / ww);
        } else if (w < h && h > hh) {
            be = (int) (newOpts.outHeight / hh);
        }
        if (be <= 0)
            be = 1;
        newOpts.inSampleSize = be;// 设置采样率

        // newOpts.inPreferredConfig = Config.ARGB_8888;//该模式是默认的,可不设
        newOpts.inPurgeable = true;// 同时设置才会有效
        newOpts.inInputShareable = true;// 。当系统内存不够时候图片自动被回收

        bitmap = BitmapFactory.decodeFile(srcPath, newOpts);
        // return compressBmpFromBmp(bitmap);//原来的方法调用了这个方法企图进行二次压缩
        // 其实是无效的,大家尽管尝试
        return bitmap;
    }

好了，可以到照片保存的位置检查一下了，已经是2M左右大小的照片了。