Vector graphics retrieval based on multi-stage architecture

This paper presents an algorithm that it can extract features from basic geometry element graphics and retrieve graphics based on multi-stage architecture.At first,the algorithm preprocesses the vector graphics. Then the graphics statistic features and structure features can be extracted from different graphic elements respectively.Those features help to describe information of graphics.The multi-stage architecture is used in this algorithm to improve efficiency of retrieval.In first retrieval,the simple statistic features,such as amount of lines or arcs,are used to match the graphics in the database in order to reduce the retrieval scope.In second retrieval,some features such as slope of line and radian of arc are used to retrieve graphics based on the results from the first retrieval.Comparing with some classic retrieval algorithms used in engineering graphics,statistic features and structure features which are extracted based on this algorithm are organized under the multi-stage architecture.The method avoids the difficult problem of normalization,in which two different types of features are described in the single vector.The experiment results indicate that this algorithm has improved accuracy and efficiency in graphic retrieval.