I Introduction
In natural scene images, texts provide highly useful information and can provide a key for understanding the image content. To extract semantics from texts in a scene, text regions should be identified first. Text region detection can be useful in many applications, such as roadsign identification and the interpretation of documents such as geographic maps or engineering drawings. There has been extensive research on text detection and recognition in recent years. However, because of the extreme diversity of text patterns together with illumination variations, distortions and other noise, text detection within a natural scene remains a difficult and challenging task. Many approaches have been proposed for the segmentation, detection and recognition of texts from document images, video sequences or natural scene images.