code: private Bitmap  checkForImageDataURL(String url)
     {
        if (!url.startsWith("data:"))
           return null;
        if (url.length() < 14)
           return null;
  
        int  comma = url.indexOf(',');
        if (comma == -1 || comma < 12)
           return null;
        if (!";base64".equals(url.substring(comma-7, comma)))
           return null;
        byte[]  imageData = Base64.decode(url.substring(comma+1), Base64.DEFAULT);
        return BitmapFactory.decodeByteArray(imageData, 0, imageData.length);
     }
docs: /*
  Check for an decode an image encoded in a data URL.
  We don't handle all permutations of data URLs. Only base64 ones.