Crops a circle out of the thumbnail photo for Android (by Daniel Olshansky @google )

Function_getCroppedBitmap

public Bitmap getCroppedBitmap(Bitmap bitmap) {
    Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), Config.ARGB_8888);

    final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());

    Canvas canvas = new Canvas(output);

    final Paint paint = new Paint();
    paint.setAntiAlias(true);

    int halfWidth = bitmap.getWidth() / 2;
    int halfHeight = bitmap.getHeight() / 2;

    canvas.drawCircle(halfWidth, halfHeight, Math.max(halfWidth, halfHeight), paint);

    paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));

    canvas.drawBitmap(bitmap, rect, rect, paint);

    return output;
}