I. Introduction
Electronic commerce offers great convenience for shopping or advertising, which is now becoming an indispensable part of our life. Driven by the increasing demand of consumers, more and more products are available for online-shopping, thousands of web images have been generated simultaneously. Text in these web images is one of the most essential forms to convey valuable information. The web text ability can facilitate applications of various kinds, such as goods surveillance, products classification, content filtering and intelligent retrieval or recommendation.