Uploading base64 results in a outofmemory error in a Android app

I'm back with a problem.

I'm trying to create a Android application that allows the user to search a image from their gallery and upload it. However on high resolution images the application will crash with a out of memory error.

The image is 1,7MB and a resolution of 1944x1944px.

After the users opens a picture from their gallery it will be loaded in a imageview, I already resized the picture to 150x150 pixels to prevent crashes there.

Code:

            Button buttonUploadImage = (Button) findViewById(R.id.uploadImage);
        buttonUploadImage.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View view){
                dialog = ProgressDialog.show(MainActivity.this, "", 
                        "Uploading...", true);  

                    new Thread(){
                        @Override
                        public void run(){



                        Bitmap bitmap = BitmapFactory.decodeFile(picturePath);         
                        ByteArrayOutputStream stream = new ByteArrayOutputStream();
                        bitmap.compress(Bitmap.CompressFormat.PNG, 100, stream);    bitmap.recycle();
                        byte [] byte_arr = stream.toByteArray();


                        String image_str = Base64.encodeToString(byte_arr, columnIndex2);
                        bitmap = null;
                        System.gc();


                        try{

                            HttpClient httpclient = new DefaultHttpClient();
                            HttpPost httppost = new HttpPost("http://example.com/android.php");

                            List<NameValuePair> pairs = new ArrayList<NameValuePair>();
                            pairs.add(new BasicNameValuePair("image", image_str));
                            httppost.setEntity(new UrlEncodedFormEntity(pairs));
                            HttpResponse response = httpclient.execute(httppost);
                            inputStream = response.getEntity().getContent();
                            //Json stuff here to handle the response and see if it succeeded or not.

Error message: (I hope this is allowed) Error message I already tried bitmap = null and System.gc() but both didn't help.

Ofcourse I can upload it in chuncks, but shouldn't Android be able to upload a 1.7MB image without any problems?

Thanks already!