Feature points that are obtained from the combined speeded-up robust feature (SURF) detector and binary robust independent elementary features (BRIEF) descriptor have a highly robust performance. These points are previously considered the ground control points (GCPs) for building a connection between the image coordinates and the corresponding geodetic coordinates. This article proposes a novel architecture to automatically and intelligently extract GCPs based on field programmable gate arrays (FPGAs). The parallelization SURF detector, BRIEF descriptor, and BRIEF matching are implemented in a single Xilinx XC7VX980T FPGA system. Word length reduction, memory-efficient parallel architecture, shift and subtraction strategies, a sliding window for separable convolution, and an optimized multispacer-scale are used to optimize the SURF detector. Improved parallel adder trees are used to accelerate the BRIEF matching. The proposed system achieves 380 frame per second (fps) with a 100 MHz clock frequency, which satisfies the real-time and low-power requirements of embedded devices. The results of the experiment demonstrate that the proposed architecture, when mapped onto a Xilinx Virtex-7 XC7VX980T FPGA device, can select the robust feature points.

中文翻译：

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基于FPGA的星载地理配准地面控制点自动提取

从组合加速鲁棒特征 (SURF) 检测器和二进制鲁棒独立基本特征 (BRIEF) 描述符获得的特征点具有高度鲁棒的性能。这些点以前被视为地面控制点 (GCP)，用于在图像坐标和相应的大地坐标之间建立连接。本文提出了一种新颖的架构，可以基于现场可编程门阵列 (FPGA) 自动智能地提取 GCP。并行化 SURF 检测器、BRIEF 描述符和 BRIEF 匹配在单个 Xilinx XC7VX980T FPGA 系统中实现。字长减少、内存高效的并行架构、移位和减法策略、可分离卷积的滑动窗口和优化的多间隔尺度用于优化 SURF 检测器。改进的并行加法器树用于加速 BRIEF 匹配。所提出的系统以 100 MHz 时钟频率实现每秒 380 帧 (fps)，满足嵌入式设备的实时性和低功耗要求。实验结果表明，所提出的架构在映射到 Xilinx Virtex-7 XC7VX980T FPGA 器件时，可以选择稳健的特征点。