Andrew T Andrew T - 1 month ago 20
Java Question

Android bitmap compress error

I am trying to take a photo from android and post it to the server but when I run the app, I can access the camera, take a photo and get a crash after accepting the photo, but the app should convert the image to base64, and send it to the server. Why? (The error is in the line 79:Encode_image class: bitmap.compress(Bitmap.CompressFormat.JPEG, 100, stream);

The crash error is :

E/BitmapFactory: Unable to decode stream: java.io.FileNotFoundException: /storage/emulated/0/test123.jpg: open failed: EACCES (Permission denied)
E/AndroidRuntime: FATAL EXCEPTION: AsyncTask #1
Process: com.example.andrei.sendphotos, PID: 3870
java.lang.RuntimeException: An error occurred while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:309)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:354)
at java.util.concurrent.FutureTask.setException(FutureTask.java:223)
at java.util.concurrent.FutureTask.run(FutureTask.java:242)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'boolean android.graphics.Bitmap.compress(android.graphics.Bitmap$CompressFormat, int, java.io.OutputStream)' on a null object reference
at com.example.andrei.sendphotos.MainActivity$Encode_image.doInBackground(MainActivity.java:79)
at com.example.andrei.sendphotos.MainActivity$Encode_image.doInBackground(MainActivity.java:72)
at android.os.AsyncTask$2.call(AsyncTask.java:295)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)


Here is my code:

public class MainActivity extends AppCompatActivity {

private Button takePhotoButton;
private String encoded_string, image_name;
private Bitmap bitmap;
private File file;
private Uri file_uri;


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

takePhotoButton = (Button) findViewById(R.id.take_photo);
takePhotoButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent i = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
getFileUri();
i.putExtra(MediaStore.EXTRA_OUTPUT, file_uri);
startActivityForResult(i, 10);
}
});
}




private void getFileUri() {
image_name= "test123.jpg";
//file = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES) + File.separator + image_name);
file = new File(Environment.getExternalStorageDirectory().getAbsolutePath() + File.separator + image_name);
file_uri = Uri.fromFile(file);
}




@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if(requestCode == 10 && resultCode == RESULT_OK){
new Encode_image().execute();
}
}


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

@Override
protected Void doInBackground(Void... params) {

bitmap = BitmapFactory.decodeFile(file_uri.getPath());
ByteArrayOutputStream stream = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.JPEG, 100, stream);


//convert stream to byte array
byte[] array = stream.toByteArray();
encoded_string = Base64.encodeToString(array, 0);
return null;
}

@Override
protected void onPostExecute(Void aVoid) {
makeRequest();
}
}

private void makeRequest() {
RequestQueue requestQueue = Volley.newRequestQueue(this);
StringRequest request = new StringRequest(Request.Method.POST, "http://192.168.1.102/AndroidFileUpload/connection.php",

new Response.Listener<String>() {
@Override
public void onResponse(String response) {

}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {

}
}) {
@Override
protected Map<String, String> getParams() throws AuthFailureError {
HashMap<String, String> map = new HashMap<>();
map.put("encoded_string", encoded_string);
map.put("image_name", image_name);

return map;
}
};
requestQueue.add(request);
}

}

Answer

The problem may be because you are getting the actual path, but you need the real path