public static Bitmap getCircleBitmap(Bitmap bitmap) {
int size = Math.min(bitmap.getWidth(), bitmap.getHeight());
Bitmap circleBmp = Bitmap.createBitmap(size, size, Bitmap.Config.ARGB_8888);
Canvas canvasTmp = new Canvas(circleBmp);
Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
canvasTmp.drawCircle(size/2, size/2, size/2, paint);
bitmap = Bitmap.createBitmap(bitmap, 0, 0, size, size);
Canvas canvas = new Canvas(bitmap);
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_IN));
canvas.drawBitmap(circleBmp, 0, 0, paint);
return bitmap;
}