A Fast and Power-Efficient Hardware Architecture for Visual Feature Detection in Affine-SIFT

Visual feature detection has been widely used in many computer vision applications, with increasing concern on feature robustness, processing speed, and power efficiency. In comparison with popular feature detection algorithms, affine-SIFT achieves the strongest robustness on the image illumination, image rotation, and image scale transformation, but exhibits extreme high computation complexity. To improve its computing efficiency, this work first proposes three hardware optimization methods to address three main performance bottlenecks. The first method is the reverse affine-based pipelined computing with optimized memory accessing. The second method is about stream processing with full parallel Gaussian pyramid. The third method is the rotation invariant binary pattern based feature vector generation. Then by incorporating these three optimization methods, this paper designs a high-efficient pipelined and parallel hardware architecture with optimized parallel memory accessing. Postlayout simulations using TSMC 65-nm 1P9M low power process show that this work achieves a processing speed of 97 fps at 1080p (1000 feature points per frame on average) under 200 MHz, with power consumption at 300 mW. In comparison, its computing efficiency (1005.6K pixels/s at 1 MHz) and power efficiency (670.5K pixels/s at 1 mW) are higher than state-of-the-art works and it is more promising for broad vision applications especially the embedded vision and mobile vision applications.