We propose an end-to-end trainable Convolutional Neural Network (CNN), named GridDehazeNet, for single image dehazing. The GridDehazeNet consists of three modules: pre-processing, backbone, and post-processing. The trainable pre-processing module can generate learned inputs with better diversity and more pertinent features as compared to those derived inputs produced by hand-selected pre-processing methods. The backbone module implements a novel attention-based multi-scale estimation on a grid network, which can effectively alleviate the bottleneck issue often encountered in the conventional multi-scale approach. The post-processing module helps to reduce the artifacts in the final output. Experimental results indicate that the GridDehazeNet outperforms the state-of-the-arts on both synthetic and real-world images. The proposed hazing method does not rely on the atmosphere scattering model, and we provide an explanation as to why it is not necessarily beneficial to take advantage of the dimension reduction offered by the atmosphere scattering model for image dehazing, even if only the dehazing results on synthetic images are concerned.

GridDehazeNet是一种端到端可训练的卷积神经网络，用于单图像去雾。其包括预处理、骨干和后处理三个模块，在预处理模块中可以生成具有更好多样性和相关特征的输入。骨干模块实现基于注意力的多尺度估计，可以有效缓解传统多尺度方法中经常遇到的瓶颈问题。后处理模块有助于减少最终输出中的伪影。实验结果表明，GridDehazeNet在合成和实际场景中都优于现有技术。提出的去雾方法不依赖于大气散射模型，并解释了为什么即使只考虑合成图像上的去雾结果，利用大气散射模型的降维优势也未必有益。

基于注意力机制的多尺度网格去雾网络