Automatic LED text recognition method on electronic road sign using local spatial pattern and random forest classifier

In the field of intelligent transportation systems (ITS), an electronic road sign (ERS) is an important device for giving a real-time traffic-related information. The ERSs generally display dynamic text information that each character consists of matrix of a light-emitting diodes lamp, named LED text. This paper addresses an LED text detection and recognition method, as an application of ITS for assisting the driver. Our method is divided into several main stages. First, the ERS is localized from the input image using color model on the RGB-color space. Second, LED text contained on the ERS are detected based on supporting points. supporting points representing as a center of LED segment on a binary map of the input image. Third, each character of LED text is recognized using local spatial pattern feature and random forest classifier. Last, the recognized characters are merged into text line. Experimental results verify that the proposed method is robust to detect and recognize the LED text.