Convert image to base64 String and vice versa

Image to base64 String

To convert image to base64 String use the code given below.

1. Define a new ByteArrayOutputStream.

java.io.ByteArrayOutputStream baos = new java.io.ByteArrayOutputStream();

2. Convert image in ImageView to Bitmap.

Bitmap bm = ((android.graphics.drawable.BitmapDrawable) imageview1.getDrawable()).getBitmap();

Or convert image in drawable folder to Bitmap.
Bitmap bm = BitmapFactory.decodeResource(getResources(), R.drawable.image);

3. Convert bitmap image to byte array and encode it to String.

bm.compress(Bitmap.CompressFormat.JPEG, 100, baos);

byte[] imageBytes = baos.toByteArray();

String imageString = android.util.Base64.encodeToString(imageBytes, android.util.Base64.DEFAULT);

Base64 String to image

1. Decode String to Byte array

byte[] imageBytes = android.util.Base64.decode(imageString, android.util.Base64.DEFAULT);

2. Convert Byte array to Bitmap

Bitmap decodedImage = BitmapFactory.decodeByteArray(imageBytes, 0, imageBytes.length);

3. Set the Bitmap as image of ImageView.

imageview1.setImageBitmap(decodedImage);

Here imageString is a base64 String.