Robotics and AI Research Group, Faculty of Electrical Engineering, Brno University of Technology, 61600 Brno, Czech Republic.
Cybernetics and Robotics Research Group, Central European Institute of Technology, Brno University of Technology, 61600 Brno, Czech Republic.
Sensors (Basel). 2021 Feb 23;21(4):1552. doi: 10.3390/s21041552.
One of the biggest challenges of training deep neural network is the need for massive data annotation. To train the neural network for object detection, millions of annotated training images are required. However, currently, there are no large-scale thermal image datasets that could be used to train the state of the art neural networks, while voluminous RGB image datasets are available. This paper presents a method that allows to create hundreds of thousands of annotated thermal images using the RGB pre-trained object detector. A dataset created in this way can be used to train object detectors with improved performance. The main gain of this work is the novel method for fully automatic thermal image labeling. The proposed system uses the RGB camera, thermal camera, 3D LiDAR, and the pre-trained neural network that detects objects in the RGB domain. Using this setup, it is possible to run the fully automated process that annotates the thermal images and creates the automatically annotated thermal training dataset. As the result, we created a dataset containing hundreds of thousands of annotated objects. This approach allows to train deep learning models with similar performance as the common human-annotation-based methods do. This paper also proposes several improvements to fine-tune the results with minimal human intervention. Finally, the evaluation of the proposed solution shows that the method gives significantly better results than training the neural network with standard small-scale hand-annotated thermal image datasets.
训练深度神经网络的最大挑战之一是需要大量的数据标注。为了训练用于目标检测的神经网络,需要数百万张标注的训练图像。然而,目前还没有可以用于训练最先进的神经网络的大规模热图像数据集,而大量的 RGB 图像数据集是可用的。本文提出了一种使用 RGB 预训练的目标检测器创建数十万张标注热图像的方法。以这种方式创建的数据集可用于训练性能得到提高的目标检测器。这项工作的主要成果是一种全新的全自动热图像标注方法。所提出的系统使用 RGB 相机、热相机、3D LiDAR 和在 RGB 域中检测物体的预训练神经网络。使用这种设置,可以运行全自动流程,对热图像进行标注,并创建自动标注的热训练数据集。结果,我们创建了一个包含数十万标注对象的数据集。这种方法可以训练出与常见的基于人工标注的方法具有相似性能的深度学习模型。本文还提出了几种改进方法,可以在最小的人工干预下微调结果。最后,对所提出的解决方案的评估表明,与使用标准的小规模手动标注热图像数据集训练神经网络相比,该方法的效果显著更好。