Efficient detection and description of geometric regions in images is a prerequisite in visual systems for localization and mapping. Such systems still rely on traditional hand-crafted methods for efficient generation of lightweight descriptors, a common limitation of the more powerful neural network models that come with high compute and specific hardware requirements. In this paper, we focus on the adaptations required by detection and description neural networks to enable their use in computationally limited platforms such as robots, mobile, and augmented reality devices. To that end, we investigate and adapt network quantization techniques to accelerate inference and enable its use on compute limited platforms. In addition, we revisit common practices in descriptor quantization and propose the use of a binary descriptor normalization layer, enabling the generation of distinctive binary descriptors with a constant number of ones. ZippyPoint, our efficient quantized network with binary descriptors, improves the network runtime speed, the descriptor matching speed, and the 3D model size, by at least an order of magnitude when compared to full-precision counterparts. These improvements come at a minor performance degradation as evaluated on the tasks of homography estimation, visual localization, and map-free visual relocalization. Code and trained models will be released upon acceptance.
翻译:图像中几何区域的有效探测和描述是定位和绘图视觉系统的一个先决条件,这些系统仍然依赖传统的手工制作方法来高效生成轻量描述器,这是对具有高计算和特定硬件要求的更强大的神经网络模型的共同限制。在本文件中,我们侧重于检测和描述神经网络所需的调整,以便能够在计算上有限的平台,如机器人、移动和增强的现实装置中使用这些网络的高效测量和描述。为此,我们调查并调整网络量化技术,以加快推断速度,使其能够在有限的计算平台上使用。此外,我们重新审视解描述器量化的常见做法,并提议使用一个二进式描述器正常化层,以便能够生成具有固定数量的独特二进制描述器。ZippipPoint,我们高效的分解网络,以二进制描述器为基础,提高网络运行速度、脱描述器匹配速度和3D模型大小,与完全精确度对应的平台相比,至少以数量顺序排列。这些改进将出现在一个小规模的平面描述中,通过经过培训的直观评估的图像分析模型,将可视化后进行局部的降解。