Encode and Decode Image in Base64 String in Android?

Converting Image to Base64 String can help in many ways like if you want to encode and decode any image or can send it to API using a retrofit.

Sending Images as Strings to API is a better way to store image data in the database.

To convert the Image to Base64 String first take the Image from either gallery or camera. Here I am using the gallery in my previous post How to open camera in Android Studio you can get Images using the camera.

Steps to Make this App

Step 1 ➤

Let’s Make a Button and an ImageView in XML Button to open the Gallery and ImageView to show the captured Image and a TextView to show base64 String.

<!-- add Gallery Button to open the Gallery -->
<Button
android:id="@+id/GalleryBtn"
android:layout_width="100dp"
android:layout_height="50dp"
android:layout_marginLeft="140dp"
android:text="Gallery" />
<!-- add ImageView to display the image -->
<ImageView
android:id="@+id/Image"
android:layout_width="350dp"
android:layout_height="450dp"
android:layout_marginLeft="15dp"
android:layout_marginTop="70dp"
android:layout_marginBottom="10dp" />
<!-- Textview to display encoded text-->
<TextView
android:id="@+id/textView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="8dp"
android:ellipsize="end"
android:maxLines="5" />

Step 3➤

Navigate to app > Manifests > AndroidManifest.xml file and add the following permission to it

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>

Step 2 ➤

Now in the MainActivity file first We will instantiate the components made in the XML file (Gallery Button, ImageView, TextView) using the findViewById() method. And define the variable pic_id which is the request-id of the clicked image.

private static final int pic_id = 123

After that Use to bellow code to open the gallery.

GalleryBtn.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
        Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
        intent.addCategory(Intent.CATEGORY_OPENABLE);
        intent.setType("image/*");
        startActivityForResult(Intent.createChooser(intent, "Select Picture"),pic_id);
    }
});

To handle the result Override the onActivityResult().

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

In onActivityResult() if (resultCode == RESULT_OK && requestCode == REQUEST_ONE) then initialize Uri, bitmap and byte Stream then compress the Bitmap and initialize byte array then encode the image in String using edcodeToString method and show it in a TextView.

Congrats Now your image is encoded in the string you can do what you want to do with this.

// when result is ok
// initialize uri
Uri uri=data.getData();
// Initialize bitmap
try {
Bitmap bitmap= MediaStore.Images.Media.getBitmap(getContentResolver(),uri);
// initialize byte stream
ByteArrayOutputStream stream=new ByteArrayOutputStream();
// compress Bitmap
bitmap.compress(Bitmap.CompressFormat.JPEG,100,stream);
// Initialize byte array
byte[] bytes=stream.toByteArray();
// get base64 encoded string
String sImage= Base64.encodeToString(bytes,Base64.DEFAULT);
// set encoded text on textview
textView.setText(sImage);

This is how you encode an Image now using the bellow code you can decode this in the bitmap and show it in ImageView.

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

Android is King.

Thank you for your time and Bye Bye.