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The Optical Bar Code Detection Method Based on Optical Camera Communication Using Discrete Fourier Transform

Optical camera communication (OCC) traditionally uses the bright and dark stripes of rolling shutter pattern captured by the complementary metal–oxide–semiconductor (CMOS) image-sensor to realize communication. For the reason that these stripes are distributed on plane space of the image, the conventional OCC is based on image space-domain. In this paper, different from the convention, we first introduce a Modulation and Image Frequency-Domain Recognition (M-IFDR) method of OCC. In this approach, LEDs are modulated to assign different frequency characteristics instead of transmitting data. Taking discrete Fourier transform (DFT) of the rolling shutter pattern to obtain the spectrum image, we can recognize the LED according to the characteristics of the spectrum image based on image frequency-domain. The experiment results show that the proposed M-IFDR method has good performance, with at least 426 recognizable LEDs and the recognition distance reaching 3m. Therefore, the proposed M-IFDR method can be considered as one of the effective methods of OCC.