We present a novel approach for real-time implementation of raw image data processing using modern hardware for material classification and pseudocolor presentation of the images in X-ray baggage inspection systems. This implementation was done using a heterogeneous hardware comprising field-programmable gate array (FPGA) and an ARM processor available in a Xilinx FPGA board. With implementation of various algorithms in the processor system and with parallel computing done in programmable logic, an improvement in the processing speed has been achieved. For denoising of images, a Wiener filter was implemented with a high-level synthesis tool. The hardware implementation of various algorithms was verified by processing about 750 images in a Xilinx FPGA board and comparing these images with software-processed images. The processing time of a 512 ×640 pixel image was 400 ms using logic clocked at 100 MHz. Experimental results demonstrate that it is preferable to implement the Wiener filter in IP core processing rather than in the ARM as the execution is about 16 times faster in this case. The static and dynamic power consumption of the hardware was estimated to be about 2% and 92% of the total power consumption of about 1.7 W. The approach of hardware-based raw data processing could be further adopted for integration with data acquisition electronics for making the inspection systems more compact and portable with cost reduction.
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