关键词：图像处理教程；基于网络的教程；命令级结构
摘 要：We present Sifter, an interface for browsing, comparing and analyzing large collections of image manipulation tutorials based on their command-level structure. Sifter first applies supervised machine learning to identify the commands contained in a collection of 2500 Photoshop tutorials obtained from theWeb.It then provides three different views of the tutorial collection based on the extracted command-level structure.