Generating a high-quality High Dynamic Range (HDR) image from dynamic scenes has recently been extensively studied by exploiting Deep Neural Networks (DNNs). Most DNNs-based methods require a large amount of training data with ground truth, requiring tedious and time-consuming work. Few-shot HDR imaging aims to generate satisfactory images with limited data. However, it is difficult for modern DNNs to avoid overfitting when trained on only a few images. In this work, we propose a novel semi-supervised approach to realize few-shot HDR imaging via two stages of training, called SSHDR. Unlikely previous methods, directly recovering content and removing ghosts simultaneously, which is hard to achieve optimum, we first generate content of saturated regions with a self-supervised mechanism and then address ghosts via an iterative semi-supervised learning framework. Concretely, considering that saturated regions can be regarded as masking Low Dynamic Range (LDR) input regions, we design a Saturated Mask AutoEncoder (SMAE) to learn a robust feature representation and reconstruct a non-saturated HDR image. We also propose an adaptive pseudo-label selection strategy to pick high-quality HDR pseudo-labels in the second stage to avoid the effect of mislabeled samples. Experiments demonstrate that SSHDR outperforms state-of-the-art methods quantitatively and qualitatively within and across different datasets, achieving appealing HDR visualization with few labeled samples.
翻译:最近,利用深度神经网络(DNNs)探索动态场景的高质量高动态范围(HDR)图像生成已经得到了广泛研究。大多数DNNs方法需要大量带有地面真实性的训练数据,需要繁琐和耗时的工作。Few-shot HDR成像旨在使用有限的数据生成令人满意的图像。然而,现代DNNs在仅训练少量图像时很难避免过拟合的问题。在本文中,我们提出了一种新的半监督方法,通过两个训练阶段实现few-shot HDR成像,称为SSHDR。与先前的方法不同,直接同时恢复内容并去除鬼影,很难实现最优化,我们首先通过自监督机制生成饱和区域的内容,然后通过迭代半监督学习框架处理鬼影。具体而言,考虑到饱和区域可以被看作遮盖LDR输入区域,我们设计了饱和度掩蔽自编码器(SMAE)来学习强大的特征表示并重建非饱和HDR图像。我们还提出了一种自适应的伪标签选择策略,在第二阶段挑选高质量的HDR伪标签,以避免混标样本的影响。实验表明,SSHDR在不同数据集内外量化和质量方面均优于现有最先进的方法,并利用少量标记样本呈现了吸引人的HDR可视化效果。