Hazy images captured under ill-posed scenarios with scattering medium (i.e. haze, fog, or smoke) are contaminated in visibility. Inevitably, these images are further degraded by noises owing to real-world imaging. Most existing hazy image enhancement methods perform image dehazing and denoising stage by stage, with the undesirable result that the estimation error of the former stage has to be propagated and amplified in the latter stage, e.g., noise amplification after dehazing. To address this inconsistent degradation, we present an Unsupervised Unified Image Dehazing and Denoising Network, U ² D ² Net, to remove the haze and suppress the noise simultaneously for a single hazy image. U ² D ² Net is mainly comprised of an unsupervised dehazing module, an unsupervised denoising module, and a regionsimilarity fusion strategy. Specifically, we propose an unsupervised transmission-aware dehazing module to restore visibility and suppress depth-dependent noise propagation in the dehazing module. Besides, we design an unsupervised network with a Mean/Max Sub-Sampler in the denoising module. To exploit the correlation and complementary between the previous outputs, a region-similarity fusion strategy is developed to compute the final qualified result. Extensive experiments on both synthetic and realworld datasets illustrate that U ² D ² Net outperforms other stateof-the-art dehazing and denoising methods in terms of PSNR, SSIM, and subjective visual effects.

Few-shot learning brings the machine close to human thinking which enables fast learning with limited samples. Recent work considers local features to achieve contextual semantic complementation, while they are merely coarsened feature observations that can only extract insignificant label correlations. On the contrary, partial properties of few-shot examples significantly draw the implicit feature observations that can reveal the underlying label correlation of rare label classification. To fully explore the correlation between labels and partial features, this paper proposes a Part-Aware Correlation Network (PACNet) based on Partial Representation (PR) and Semantic Covariance Matrix (SCM). Specifically, we develop a partial representing module of an object that eliminates object-independent information and allows the model to focus on more distinctive parts. Furthermore, a semantic covariance measure function is redefined as a way to learn the semantic relationships of partial representations and to compute the partial similarity between the query sample and the support set. Experiments on three benchmark datasets consistently show that the proposed method outperforms the state-of-the-art counterparts, e.g. , on the PartImageNet dataset, the performance gains of up to 12% and 5.9% are observed for the 5-way 1-shot and 5-way 5-shot settings, respectively.