I checked an image with given link http://freeonlinetools24.com/base64-image and it works fine. I think the reason for getting wrong output is your string. Encoded string always ends with == . Check your encoded string.
Example Code
Encode Image
BitmapDrawable drawable = (BitmapDrawable) imgPreview.getDrawable();
Bitmap bitmap = drawable.getBitmap();
encodedImage = encodeToBase64(bitmap, Bitmap.CompressFormat.JPEG, 100);
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);
}
Decode Image
Bitmap bitmap = decodeBase64(encodedImage );
img.setImageBitmap(bitmap);
public static Bitmap decodeBase64(String input)
{
byte[] decodedBytes = Base64.decode(input,0);
return BitmapFactory.decodeByteArray(decodedBytes, 0, decodedBytes.length);
}
EDITED
see my string..
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