基于关键点的遥感图像舰船目标检测

Key-point based method for ship detection in remote sensing images

针对当前舰船目标检测算法存在锚框遍历计算成本高和特征旋转适应性不足等问题,提出基于关键点的遥感图像舰船目标检测方法,通过预估舰船中心点实现目标检测。首先,引入深度可分离卷积降低参数冗余,结合SimAM无参注意力机制,增强对舰船目标的关注度。其次,引入方向不变模型(orientation-invariant model, OIM)生成方向不变特征图,增强网络对旋转目标的适应能力。最后,考虑到遥感图像舰船目标任意方向密集排列,但舰船目标中心点不变的特点,采用直接预测目标的中心点,再回归偏移量、目标尺度和角度的思路,摆脱锚框遍历机制,提高检测速度。在HRSC2016和RFUE2021数据集上进行对比实验,实验结果充分说明了本文方法的有效性和先进性。

Problems with current ship target detection method, such as high computational cost of anchor frame traversal;and the rotation invariance of the features extracted from the backbone network is weak and cannot adapt to the ship targets in any direction, resulting in inconsistency. Therefore, a ship target detection method based on key points in remote sensing images is proposed, and the target detection is realized by predicting the ship center point. First, the depth separable convolution is added to reduce the parameter redundancy, and the attention to the ship target is enhanced combined with SimAM nonparametric attention. Second, the orientation-invariant model(OIM) is introduced to generate the orientation-invariant feature map to enhance the adaptability of the network to target rotation. Finally, considering that the ship targets in remote sensing images are densely arranged in any direction, but the center point of the ship target is constant, the idea of directly predicting the center point of the target, and then regressing the offset, target scale and angle is adopted to get rid of the anchor frame traversal mechanism and improve the detection speed. A comparative experiment was conducted on the HRSC2016 and RFUE2021 datasets, and the experimental results fully demonstrate the effectiveness of the proposed method.