双线性插值，又称为双线性内插。在数学上，双线性插值是有两个变量的插值函数的线性插值扩展，其核心思想是在两个方向分别进行一次线性插值。双线性插值作为数值分析中的一种插值算法，广泛应用在信号处理，数字图像和视频处理等方面。(Bilinear interpolation is also called bilinear interpolation. In mathematics, bilinear interpolation is a linear interpolation expansion of interpolation functions with two variables. Its core idea is to interpolate linearly in two directions. Bilinear interpolation is a kind of interpolation algorithm in numerical analysis, which is widely used in signal processing, digital image and video processing.)