Image search engine is a brand new search engine, currently there is Antu Search in China. Extraction based on image form features: The image analysis software automatically extracts the color, shape, texture and other features of the image and establishes a feature index library. Users only need to describe the general features of the image they are looking for to find similar features. image. This is a mechanical matching based on the image feature hierarchy, which is particularly suitable for query requirements with clear retrieval goals (such as trademark retrieval). The results produced are also closest to user requirements. However, this relatively mature retrieval technology is currently mainly used in retrieval of image databases. There are still certain difficulties in applying this retrieval technology in online image search engines.