说明：  函数主要实现图像处理过程中由于旋转缩放导致坐标不在整数位置，使用原始像素对当前像素点的计算方法：双线性插值！
(The main function is to achieve image processing result in the rotation of the zoom position coordinates are not integers, the calculation method using the original pixel of the current pixel: bilinear interpolation!)