In order to decrease the calculation complexity, this method uses heat conduct equation instead of chrominance blending for making the ridge of color blocks smooth.

• 该方法以不平度作为颜色扩展的约束条件，使用热传导方程来代替颜色混合方法使色块边缘更加平滑，从而大大降低了运算复杂度、提高了彩色化效率。