histogram mapping

• 灰度直方图

histogram mapping的用法和样例：

例句

1. This paper presents a method of determining the type of vehicle-license-plate based on the gradient histogram and the gray histogram of the image of a vehicle-license-plate.
   本文提出一种基于车牌图像梯度直方图和灰度直方图确定车牌类型的方法。