An image gradient based LED bit detection algorithm in vehicular optical camera communication

Abstract

Information in vehicular optical camera communication (VOCC) systems is transmitted using LED arrays, which are also vehicle lights functioning both illumination and communication. Logical bits 1 and 0 are conveyed by the status On and Off of LED chips in the array. Cameras are installed in the receiving vehicles to capture the images of these LED arrays. These images are then processed to detect the status On and Off of LED chips and thus obtain the transmitted bits. In current LED bit detection algorithms, the grayscales of LEDs, which is an unreliable feature, is used to determine the LED status and thus have poor performances in unfavorable conditions. This study proposes a new LED bit detection algorithm that exploits gradient vectors in the image to significantly increase the detection accuracy even in unfavorable conditions of VOCC system. Simulations are conducted to verify the performance of the proposed algorithm. © 2019 IEEE.