System Architecture for Real-Time Face Detection on Analog Video Camera

This paper proposes a novel hardware architecture for real-time face detection, which is efficient and suitable for embedded systems. The proposed architecture is based on AdaBoost learning algorithm with Haar-like features and it aims to apply face detection to a low-cost FPGA that can be applied to a legacy analog video camera as a target platform. We propose an efficient method to calculate the integral image using the cumulative line sum. We also suggest an alternative method to avoid division, which requires many operations to calculate the standard deviation. A detailed structure of system elements for image scale, integral image generator, and pipelined classifier that purposed to optimize the efficiency between the processing speed and the hardware resources is presented. The performance of the proposed architecture is described in comparison with the detection results of OpenCV using the same input images. For verification of the actual face detection on analog cameras, we designed an emulation platform using a low-cost Spartan-3 FPGA and then experimented the proposed architecture. The experimental results show that the processing time for face detection on analog video camera is 42 frames per second, which is about 3 times faster than previous works for low-cost face detection.