public Bitmap scalingBitmap(Bitmap bitmap, int newW, int newH) {
		int w = bitmap.getWidth();
		int h = bitmap.getHeight();
		float sx = (float) newW / w;
		float sy = (float) newH / h;
		Matrix matrix = new Matrix();
		matrix.postScale(sx, sy); // 长和宽放大缩小的比例
		return Bitmap.createBitmap(bitmap, 0, 0, w, h, matrix, true);
	}