android – Take picture and convert to Base64-ThrowExceptions

Exception or error:

I use code below to make a picture with camera. Instead of saving I would like to encode it to Base64 and after that pass it to another API as an input. I can’t see method, how to modify code to take pictures in Base64 instead of regular files.

public class CameraDemoActivity extends Activity {
    int TAKE_PHOTO_CODE = 0;
    public static int count = 0;

    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        final String dir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES) + "/picFolder/";
        File newdir = new File(dir);
        newdir.mkdirs();

        Button capture = (Button) findViewById(R.id.btnCapture);
        capture.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                count++;
                String file = dir+count+".jpg";
                File newfile = new File(file);
                try {
                    newfile.createNewFile();
                }
                catch (IOException e)
                {
                }

                Uri outputFileUri = Uri.fromFile(newfile);

                Intent cameraIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                cameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, outputFileUri);

                startActivityForResult(cameraIntent, TAKE_PHOTO_CODE);
            }
        });
    }

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

        if (requestCode == TAKE_PHOTO_CODE && resultCode == RESULT_OK) {
            Log.d("CameraDemo", "Pic saved");
        }
    }
}

I try to use code below to convert an image to Base64.

public static String encodeToBase64(Bitmap image, Bitmap.CompressFormat compressFormat, int quality)
{
    ByteArrayOutputStream byteArrayOS = new ByteArrayOutputStream();
    image.compress(compressFormat, quality, byteArrayOS);
    return Base64.encodeToString(byteArrayOS.toByteArray(), Base64.DEFAULT);
}

Above described should be a much more direct and easier way than saving image and after that looking for image to encode it.

How to solve:

Try this:
ImageUri to Bitmap:

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

            if (requestCode == TAKE_PHOTO_CODE && resultCode == RESULT_OK) {
                final Uri imageUri = data.getData();
                final InputStream imageStream = getContentResolver().openInputStream(imageUri);
                final Bitmap selectedImage = BitmapFactory.decodeStream(imageStream);
                String encodedImage = encodeImage(selectedImage);
            }
        }

Encode Bitmap in base64

   private String encodeImage(Bitmap bm)
    {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        bm.compress(Bitmap.CompressFormat.JPEG,100,baos);
        byte[] b = baos.toByteArray();
        String encImage = Base64.encodeToString(b, Base64.DEFAULT);

        return encImage;
    }

Encode from FilePath to base64

 private String encodeImage(String path)
    {
        File imagefile = new File(path);
        FileInputStream fis = null;
        try{
            fis = new FileInputStream(imagefile);
        }catch(FileNotFoundException e){
            e.printStackTrace();
        }
        Bitmap bm = BitmapFactory.decodeStream(fis);
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        bm.compress(Bitmap.CompressFormat.JPEG,100,baos);
        byte[] b = baos.toByteArray();
        String encImage = Base64.encodeToString(b, Base64.DEFAULT);
        //Base64.de
        return encImage;

    }

output:
enter image description here

###

I’ve wrote my code like this :

public class MainActivity extends AppCompatActivity {

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

        Camera mCamera = Camera.open();
        mCamera.startPreview();// I don't know why I added that, 
                               // but without it doesn't work... :D

        mCamera.takePicture(null, null, mPicture);
    }

    private Camera.PictureCallback mPicture = new Camera.PictureCallback() {

        @Override
        public void onPictureTaken(byte[] data, Camera camera) {
            System.out.println("***************");
            System.out.println(Base64.encodeToString(data, Base64.DEFAULT));
            System.out.println("***************");
        }
    };
}

It works perfectly…

###

Just for converting from bitmap to base64 string in kotlin I use:

private fun encodeImage(bm: Bitmap): String? {
        val baos = ByteArrayOutputStream()
        bm.compress(Bitmap.CompressFormat.JPEG, 100, baos)
        val b = baos.toByteArray()
        return Base64.encodeToString(b, Base64.DEFAULT)
    }

Leave a Reply

Your email address will not be published. Required fields are marked *