Encode-Upload and Decode-Download Bitmap using Base64 in android

Question

I build an android application using "Android Studio" that upload images after compress and encode it using base64 and save it at server in string format, then download it (PHP send images strings using JSON). after decoding the image some image is showing normally but other not (the most images doesn't appear).

I search and try many posted solution, but nothing worked properly, please any help.

this is my android java code:

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

private static final int RESULT_LOAD_IMAGE = 1;

ImageView imagetoupload, imagetodownload;
Button up_bt, dw_bt;
EditText etuploadname, etdownname;
String get_etdownname, down_user_pic, encodedImage;
Bitmap decodedByte;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    imagetoupload = (ImageView) findViewById(R.id.imagetoupload);
    imagetodownload = (ImageView) findViewById(R.id.imagetodownload);

    up_bt = (Button) findViewById(R.id.up_bt);
    dw_bt = (Button) findViewById(R.id.dw_bt);

    etuploadname = (EditText) findViewById(R.id.etuploadname);
    etdownname = (EditText) findViewById(R.id.etdownname);

    up_bt.setOnClickListener(this);
    dw_bt.setOnClickListener(this);
    imagetoupload.setOnClickListener(this);
}

@Override
public void onClick(View v) {
    switch (v.getId()) {
        case R.id.imagetoupload:

            Intent galleryIntent = new Intent(Intent.ACTION_PICK, MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
            startActivityForResult(galleryIntent, RESULT_LOAD_IMAGE);

            break;

        case R.id.up_bt:

            Bitmap image = ((BitmapDrawable) imagetoupload.getDrawable()).getBitmap();
            new UploadImage(image, etuploadname.getText().toString()).execute();

            break;

        case R.id.dw_bt:

            get_etdownname = etdownname.getText().toString();
            DownloadBackGround b = new DownloadBackGround();
            b.execute(get_etdownname);

            break;
    }
}

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

    if (requestCode == RESULT_LOAD_IMAGE && resultCode == RESULT_OK && data != null) {
        Uri selectedimage = data.getData();
        imagetoupload.setImageURI(selectedimage);
    }
}

private class UploadImage extends AsyncTask<Void, Void, Void> {

    Bitmap image;
    String name;

    public UploadImage(Bitmap image, String name) {
        this.image = image;
        this.name = name;
    }

    @SuppressWarnings("ResourceType")
    @Override
    protected Void doInBackground(Void... params) {

        String data = "";
        int tmp;

        ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
        image.compress(Bitmap.CompressFormat.PNG, 100, byteArrayOutputStream);

        encodedImage = Base64.encodeToString(byteArrayOutputStream.toByteArray(), Base64.DEFAULT);
        Log.d("Me", encodedImage);

        try {
            URL url = new URL("------ my url -------");
            String urlParams = "image=" + encodedImage + "&name=" + name;

            HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
            httpURLConnection.setDoOutput(true);

            OutputStream os = httpURLConnection.getOutputStream();
            os.write(urlParams.getBytes());
            os.flush();
            os.close();

            InputStream is = httpURLConnection.getInputStream();
            while ((tmp = is.read()) != -1) {
                data += (char) tmp;
            }
            is.close();

            httpURLConnection.disconnect();

            Log.e("Me", data + "");

            //  return data;

        } catch (IOException e) {
            e.printStackTrace();
            // return "Exception: " + e.getMessage();
        }

        return null;
    }

    @Override
    protected void onPostExecute(Void aVoid) {
        super.onPostExecute(aVoid);
        Toast.makeText(getApplicationContext(), "image uploaded", Toast.LENGTH_LONG).show();


        byte[] decodedString = Base64.decode(encodedImage.getBytes(), Base64.DEFAULT);
        Bitmap decodedByte = BitmapFactory.decodeByteArray(decodedString, 0, decodedString.length);
        imagetodownload.setImageBitmap(decodedByte);

        imagetodownload.setImageBitmap(decodedByte);
    }
}


////////////////////////////download /////////////////////////////

class DownloadBackGround extends AsyncTask<String, String, String> {

    @Override
    protected String doInBackground(String... params) {
        String name_pic = params[0];

        try {
            URL url = new URL("------ my url ------");
            String urlParams = "name=" + name_pic;

            HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
            httpURLConnection.setDoOutput(true);

            OutputStream os = httpURLConnection.getOutputStream();
            os.write(urlParams.getBytes());
            os.flush();
            os.close();

            InputStream is = httpURLConnection.getInputStream();
            BufferedReader reader = new BufferedReader(new InputStreamReader(is));
            StringBuilder buffer = new StringBuilder();
            String line;

            while ((line = reader.readLine()) != null) {
                buffer.append(line);
            }
            is.close();
            httpURLConnection.disconnect();

            return buffer.toString();

        } catch (MalformedURLException e) {
            e.printStackTrace();
            return "Exception: " + e.getMessage();
        } catch (IOException e) {
            e.printStackTrace();
            return "Exception: " + e.getMessage();
        }
    }

    @Override
    protected void onPostExecute(String result) {
        super.onPostExecute(result);

        if (result.equals("2")) {
            Log.e("Me", "No picture in this name");
        } else {
            Log.e("Me", result);

            try {
                JSONObject parentObject = new JSONObject(result);
                JSONArray parentArray = parentObject.getJSONArray("result");

                JSONObject finalObject = parentArray.getJSONObject(0);

                down_user_pic = finalObject.getString("pic_byte");

            } catch (JSONException e) {
                e.printStackTrace();
            }

            //// decode picture and set here

            Log.d("Me", down_user_pic);

            byte[] decodedString = Base64.decode(down_user_pic.getBytes(), Base64.DEFAULT);
            decodedByte = BitmapFactory.decodeByteArray(decodedString, 0, decodedString.length);
            imagetodownload.setImageBitmap(decodedByte);

        }
    }
}

///////////////////////////////Download //////////////////////////

and this is my uploading php code:

       <?php require "init.php";

      // Check connection

      if (!$con) {
       die("Connection failed: " . mysqli_connect_error());
       }

     $image = $_REQUEST["image"];
     $name = $_POST["name"];
     $image = str_replace(" ", "+", $image);
     $id= uniqid();
     //$decodedImage = base64_decode("$image");

    $sql = "INSERT INTO `pictures` (`id`, `pic_id`, `pic_byte`) VALUES          ('".$id."', '".$name."', '".$image."');";     
   if(!mysqli_query($con, $sql)){
    }
     ?>

and this is my downloading php code:

<?php
require "init.php";

// Check connection

if (!$con) {
     die("Connection failed: " . mysqli_connect_error());
}

$name = $_POST["name"];

$id= uniqid();


$sql = "SELECT * FROM pictures WHERE `pic_id`='".$name."'";

$res = mysqli_query($con,$sql); 
$result = array();

while($row = mysqli_fetch_array($res)){   
      array_push($result,
      array('pic_byte'=>$row[2])); 
      }

$string1 = '{"result":[]}';
$string2 = json_encode(array("result"=>$result));

$pos = strspn($string1 ^ $string2, "\0");

if($string1[$pos]=="" && $string2[$pos] == ""){  
             echo "2";
            }else {
            echo $string2;
            } 

?>

this logcat was show:

   04-20 11:39:31.184 18472-18472/com.example.aly.updownpic D/dalvikvm: GC_FOR_ALLOC freed 1765K, 44% free 7473K/13340K, paused 17ms, total 21ms
    04-20 11:39:31.184 18472-18472/com.example.aly.updownpic I/dalvikvm-heap: Grow heap (frag case) to 13.192MB for 4080016-byte allocation
    04-20 11:39:31.234 18472-18472/com.example.aly.updownpic D/skia: --- decoder->decode returned false

UPDATE

I used JPEG but less than half of the picture is show

this is the screenshot of the picture

We've had this exact same problem when we were using PNG as the compression type. We switched to JPEG and it fixed it. — the-ginger-geek, Apr 20 '16 at 08:33
There is similar question with accepted answer http://stackoverflow.com/questions/9224056/android-bitmap-to-base64-string — Mykhailo Yuzheka, Apr 20 '16 at 08:35
Dont compress the image ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream(); image.compress(Bitmap.CompressFormat.PNG, 100, byteArrayOutputStream); , convert direct image into base64 and compare the result !! — Jhaman Das, Apr 20 '16 at 08:48
So another thing you can try is changing your request type from GET to POST on the client side. Your server side is already expecting a post (somewhat) so that wouldn't have to change. Not sure if this will work, just don't think it's a great idea posting the encoded image as a parameter. — the-ginger-geek, Apr 20 '16 at 08:57

Encode-Upload and Decode-Download Bitmap using Base64 in android

0 Answers0