FPGA-based real-time citrus classification system

Commonly, in the citrus industry in Mexico, fruit grading is performed by humans through visual inspection. Manual inspection implies several problems in maintaining grading consistency and sorting uniformity. Citrus classification is normally achieved based on external visible criteria, such as size, shape and color. This problem has been addressed using computer vision algorithms, but an automatic grading machine based on computer vision usually requires large computational resources in order to perform the classification due to the complexity of the computer vision operators. This paper describes an embedded color-based citrus selection system implemented on a field programmable gate array (FPGA) device. Experimental results show that the proposed hardware architecture is able to process 720p color images at 30 fps. The proposed architecture was validated on a Spartan-6 FPGA and the hardware resource utilization is reported.