''Preface Logo recognition is of great interest in the document and shape matching domain. Logos can act as a valuable means of identifying sources of documents. By recognizing the logo, semantic information about the document is obtained which may be useful to decide whether or not to analyze the textual parts. Some promising results have been found for clean logos; however, they can hardly be robust for noisy logos. This book summarizes our recent research on logo recognition. We first in this book (Chapter 2) provide some introduction and fundamental knowledge for pattern recognition. Readers can safely skip reading it if you feel you are familiar with these topics. In order to develop a logo recognition method that is robust to be employed under adverse conditions such as different broken curves, added noise and occlusion, a logo recognition system based on line pattern features is proposed in this book. To achieve the desired accuracy and effciency, the proposed system employs a three-stage hierarchy, polygonal approximation, indexing and matching. In the first stage, the raw logos are transformed into normalized line segment maps (LSM); in the second stage, effective line pattern features are used to index the database to generate a moderate number of likely models with respect to a test image; in the third stage, an improved Line Segment Hausdor Distance (LHD) measure is proposed to screen further and generate the best matches''--Provided by publisher.