alignment tool的用法和样例：
例句
- By setting a one-dimensional line tool across the image and calculating the grayscale difference across this line, a series of points will be generated throughout the frames.
通过设置横宽图像一维线工具并计算横跨线的灰阶差异，可以在所有的帧中生成一系列的点。 - This is an online tool which allows you to analyze frontpage stories and determine a host of factors related to the tipping point when a story goes popular.
这是一个在线工具，它可以让你分析首页文章并且找出一篇文章流行时影响它流行的关键点。
