图像质量评估（IQA）是图像处理任务（例如压缩）的基本指标。使用了全参考iQA，使用了传统的智商，例如PSNR和SSIM。最近，还使用了基于深神经网络（深IQA）的IQA，例如LPIPS和DIST。众所周知，图像缩放在深IQA中是不一致的，因为有些则在预处理中执行下降，而另一些则使用原始图像大小。在本文中，我们表明图像量表是影响深度IQA性能的影响因素。我们在同一五个数据集上全面评估了四个深IQA，实验结果表明，图像量表会显着影响IQA性能。我们发现，最合适的图像量表通常既不是默认尺寸也不是原始大小，并且选择取决于所使用的方法和数据集。我们看到了稳定性，发现PIEAPP是四个深IQA中最稳定的。

Image quality assessment (IQA) forms a natural and often straightforward undertaking for humans, yet effective automation of the task remains highly challenging. Recent metrics from the deep learning community commonly compare image pairs during training to improve upon traditional metrics such as PSNR or SSIM. However, current comparisons ignore the fact that image content affects quality assessment as comparisons only occur between images of similar content. This restricts the diversity and number of image pairs that the model is exposed to during training. In this paper, we strive to enrich these comparisons with content diversity. Firstly, we relax comparison constraints, and compare pairs of images with differing content. This increases the variety of available comparisons. Secondly, we introduce listwise comparisons to provide a holistic view to the model. By including differentiable regularizers, derived from correlation coefficients, models can better adjust predicted scores relative to one another. Evaluation on multiple benchmarks, covering a wide range of distortions and image content, shows the effectiveness of our learning scheme for training image quality assessment models.

现有的感知相似性指标假定图像及其参考非常适合。结果，这些指标通常对人眼无法察觉的小对齐误差敏感。本文研究了微小的未对准的影响，特别是输入图像和参考图像之间对现有指标的微小变化，并因此发展了耐转移的相似性度量。本文以LPIP为基础，这是一种广泛使用的知觉相似性度量，并探索了建筑设计注意事项，以使其可抵抗不可察觉的未对准。具体而言，我们研究了广泛的神经网络元素，例如抗异化滤波，汇总，跨性别，填充和跳过连接，并讨论它们在制作强大度量方面的作用。根据我们的研究，我们开发了一种新的基于神经网络的知觉相似性度量。我们的实验表明，我们的指标宽容不可察觉的转变，同时与人类的相似性判断一致。

图像质量评估（IQA）指标被广泛用于定量估计一些形成，恢复，转换或增强算法后图像降解的程度。我们提出了Pytorch图像质量（PIQ），这是一个以可用性为中心的库，其中包含最受欢迎的现代IQA算法，并保证根据其原始命题正确实现并进行了彻底验证。在本文中，我们详细介绍了图书馆基础背后的原则，描述了使其可靠的评估策略，提供了展示性能时间权衡的基准，并强调了GPU加速的好处Pytorch后端。Pytorch图像质量是一个开源软件：https：//github.com/photosynthesis-team/piq/。

现有的基于深度学习的全参考IQA（FR-IQA）模型通常通过明确比较特征，以确定性的方式预测图像质量，从而衡量图像严重扭曲的图像是多远，相应的功能与参考的空间相对远。图片。本文中，我们从不同的角度看这个问题，并提议从统计分布的角度对知觉空间中的质量降解进行建模。因此，根据深度特征域中的Wasserstein距离来测量质量。更具体地说，根据执行最终质量评分，测量了预训练VGG网络的每个阶段的1Dwasserstein距离。 Deep Wasserstein距离（DEEPWSD）在神经网络的功能上执行的，可以更好地解释由各种扭曲引起的质量污染，并提出了高级质量预测能力。广泛的实验和理论分析表明，在质量预测和优化方面，提出的DEEPWSD的优越性。

Subjective image-quality measurement plays a critical role in the development of image-processing applications. The purpose of a visual-quality metric is to approximate the results of subjective assessment. In this regard, more and more metrics are under development, but little research has considered their limitations. This paper addresses that deficiency: we show how image preprocessing before compression can artificially increase the quality scores provided by the popular metrics DISTS, LPIPS, HaarPSI, and VIF as well as how these scores are inconsistent with subjective-quality scores. We propose a series of neural-network preprocessing models that increase DISTS by up to 34.5%, LPIPS by up to 36.8%, VIF by up to 98.0%, and HaarPSI by up to 22.6% in the case of JPEG-compressed images. A subjective comparison of preprocessed images showed that for most of the metrics we examined, visual quality drops or stays unchanged, limiting the applicability of these metrics.

Deep learning-based full-reference image quality assessment (FR-IQA) models typically rely on the feature distance between the reference and distorted images. However, the underlying assumption of these models that the distance in the deep feature domain could quantify the quality degradation does not scientifically align with the invariant texture perception, especially when the images are generated artificially by neural networks. In this paper, we bring a radical shift in inferring the quality with learned features and propose the Deep Image Dependency (DID) based FR-IQA model. The feature dependency facilitates the comparisons of deep learning features in a high-order manner with Brownian distance covariance, which is characterized by the joint distribution of the features from reference and test images, as well as their marginal distributions. This enables the quantification of the feature dependency against nonlinear transformation, which is far beyond the computation of the numerical errors in the feature space. Experiments on image quality prediction, texture image similarity, and geometric invariance validate the superior performance of our proposed measure.

在这项工作中，我们介绍了梯度暹罗网络（GSN）进行图像质量评估。所提出的方法熟练地捕获了全参考图像质量评估（IQA）任务中扭曲的图像和参考图像之间的梯度特征。我们利用中央微分卷积获得图像对中隐藏的语义特征和细节差异。此外，空间注意力指导网络专注于与图像细节相关的区域。对于网络提取的低级，中级和高级功能，我们创新设计了一种多级融合方法，以提高功能利用率的效率。除了常见的均方根错误监督外，我们还进一步考虑了批处理样本之间的相对距离，并成功地将KL差异丢失应用于图像质量评估任务。我们在几个公开可用的数据集上试验了提出的算法GSN，并证明了其出色的性能。我们的网络赢得了NTIRE 2022感知图像质量评估挑战赛1的第二名。

视频框架插值（VFI）是许多视频处理应用程序的有用工具。最近，它也已应用于视频压缩域中，以增强常规视频编解码器和基于学习的压缩体系结构。尽管近年来，人们对增强框架插值算法的发展的重点越来越大，但插值内容的感知质量评估仍然是一个开放的研究领域。在本文中，我们为VFI（Flolpips）介绍了一个定制的完整参考视频质量指标，该指标基于流行的感知图像质量指标LPIP，该指标LPIPS捕获了提取的图像特征空间中的感知降解。为了提高LPIP的性能用于评估插值内容，我们通过使用时间失真（通过比较光流）来加重特征差图图，重新设计了其空间特征聚合步骤。在BVI-VFI数据库中进行了评估，该数据库包含180个带有各种框架插值伪像的测试序列，Flolpips显示出优异的相关性能（具有统计学意义），主观地面真相超过12位流行的质量评估者。为了促进VFI质量评估的进一步研究，我们的代码可在https://danielism97.github.io/flolpips上公开获得。

本文报告了NTIRE 2022关于感知图像质量评估（IQA）的挑战，并与CVPR 2022的图像恢复和增强研讨会（NTIRE）研讨会（NTIRE）讲习班的新趋势举行。感知图像处理算法。这些算法的输出图像与传统扭曲具有完全不同的特征，并包含在此挑战中使用的PIP数据集中。这个挑战分为两条曲目，一个类似于以前的NTIRE IQA挑战的全参考IQA轨道，以及一条侧重于No-Reference IQA方法的新曲目。挑战有192和179名注册参与者的两条曲目。在最后的测试阶段，有7和8个参与的团队提交了模型和事实表。几乎所有这些都比现有的IQA方法取得了更好的结果，并且获胜方法可以证明最先进的性能。

基于深度学习的立体图像超分辨率（StereOSR）的最新研究促进了Stereosr的发展。但是，现有的立体声模型主要集中于改善定量评估指标，并忽略了超级分辨立体图像的视觉质量。为了提高感知性能，本文提出了第一个面向感知的立体图像超分辨率方法，通过利用反馈，这是对立体声结果的感知质量的评估提供的。为了为StereOSR模型提供准确的指导，我们开发了第一个特殊的立体图像超分辨率质量评估（StereOSRQA）模型，并进一步构建了StereOSRQA数据库。广泛的实验表明，我们的Stereosr方法显着提高了感知质量，并提高了立体声图像的可靠性以进行差异估计。

在极低光线条件下捕获图像会对标准相机管道带来重大挑战。图像变得太黑了，太吵了，这使得传统的增强技术几乎不可能申请。最近，基于学习的方法已经为此任务显示了非常有希望的结果，因为它们具有更大的表现力能力来允许提高质量。这些研究中的激励，在本文中，我们的目标是利用爆破摄影来提高性能，并从极端暗的原始图像获得更加锐利和更准确的RGB图像。我们提出的框架的骨干是一种新颖的粗良好网络架构，逐步产生高质量的输出。粗略网络预测了低分辨率，去噪的原始图像，然后将其馈送到精细网络以恢复微尺的细节和逼真的纹理。为了进一步降低噪声水平并提高颜色精度，我们将该网络扩展到置换不变结构，使得它作为输入突发为低光图像，并在特征级别地合并来自多个图像的信息。我们的实验表明，我们的方法通过生产更详细和相当更高的质量的图像来引起比最先进的方法更令人愉悦的结果。

随着移动平台上对计算摄影和成像的需求不断增长，在相机系统中开发和集成了高级图像传感器与新型算法的发展。但是，缺乏用于研究的高质量数据以及从行业和学术界进行深入交流的难得的机会限制了移动智能摄影和成像（MIPI）的发展。为了弥合差距，我们引入了第一个MIPI挑战，其中包括五个专注于新型图像传感器和成像算法的曲目。在本文中，引入了QUAD Remosaic和Denoise，这是五个曲目之一，在完全分辨率上进行了四QFA插值向拜耳进行插值。为参与者提供了一个新的数据集，包括70（培训）和15个（验证）高品质四边形和拜耳对的场景。此外，对于每个场景，在0dB，24dB和42dB上提供了不同噪声水平的四边形。所有数据均在室外和室内条件下使用四边形传感器捕获。最终结果使用客观指标，包括PSNR，SSIM，LPIPS和KLD。本文提供了此挑战中所有模型的详细描述。有关此挑战的更多详细信息以及数据集的链接，请访问https://github.com/mipi-challenge/mipi2022。

Single image super-resolution is the task of inferring a high-resolution image from a single low-resolution input. Traditionally, the performance of algorithms for this task is measured using pixel-wise reconstruction measures such as peak signal-to-noise ratio (PSNR) which have been shown to correlate poorly with the human perception of image quality. As a result, algorithms minimizing these metrics tend to produce over-smoothed images that lack highfrequency textures and do not look natural despite yielding high PSNR values.We propose a novel application of automated texture synthesis in combination with a perceptual loss focusing on creating realistic textures rather than optimizing for a pixelaccurate reproduction of ground truth images during training. By using feed-forward fully convolutional neural networks in an adversarial training setting, we achieve a significant boost in image quality at high magnification ratios. Extensive experiments on a number of datasets show the effectiveness of our approach, yielding state-of-the-art results in both quantitative and qualitative benchmarks.

This paper introduces a novel large dataset for examplebased single image super-resolution and studies the stateof-the-art as emerged from the NTIRE 2017 challenge. The challenge is the first challenge of its kind, with 6 competitions, hundreds of participants and tens of proposed solutions. Our newly collected DIVerse 2K resolution image dataset (DIV2K) was employed by the challenge. In our study we compare the solutions from the challenge to a set of representative methods from the literature and evaluate them using diverse measures on our proposed DIV2K dataset. Moreover, we conduct a number of experiments and draw conclusions on several topics of interest. We conclude that the NTIRE 2017 challenge pushes the state-ofthe-art in single-image super-resolution, reaching the best results to date on the popular Set5, Set14, B100, Urban100 datasets and on our newly proposed DIV2K.

最近，Deep Models已经建立了SOTA性能，用于低分辨率图像介绍，但它们缺乏与现代相机（如4K或更多相关的现代相机）以及大孔相关的分辨率的保真度。我们为4K及以上代表现代传感器的照片贡献了一个介绍的基准数据集。我们展示了一个新颖的框架，结合了深度学习和传统方法。我们使用现有的深入介质模型喇嘛合理地填充孔，建立三个由结构，分割，深度组成的指南图像，并应用多个引导的贴片amatch，以产生八个候选候选图像。接下来，我们通过一个新型的策划模块来喂食所有候选构图，该模块选择了8x8反对称成对偏好矩阵的列求和良好的介绍。我们框架的结果受到了8个强大基线的用户的压倒性优先，其定量指标的改进高达7.4，而不是最好的基线喇嘛，而我们的技术与4种不同的SOTA配对时，我们的技术都会改善每个座椅，以使我们的每个人都非常偏爱用户，而不是用户偏爱用户。强大的超级分子基线。

The structural similarity image quality paradigm is based on the assumption that the human visual system is highly adapted for extracting structural information from the scene, and therefore a measure of structural similarity can provide a good approximation to perceived image quality. This paper proposes a multi-scale structural similarity method, which supplies more flexibility than previous single-scale methods in incorporating the variations of viewing conditions. We develop an image synthesis method to calibrate the parameters that define the relative importance of different scales. Experimental comparisons demonstrate the effectiveness of the proposed method.

衡量图像的相似性是计算机视觉的基本问题，不存在通用解决方案。尽管已显示出像素的L2-Norm这样的简单指标，例如L2-Norm具有很大的缺陷，但它们仍然受欢迎。一组最新的最新指标减轻了其中一些缺陷是深度的知觉相似性（DPS）指标，其中将相似性评估为神经网络深度特征的距离。但是，DPS指标本身还没有彻底检查其利益，尤其是其缺陷。这项工作研究了最常见的DPS度量，其中通过空间位置进行了比较的深度特征，并比较了平均和排序的深度特征。对指标进行了深入分析，以通过使用专门挑战它们的图像来了解指标的优势和劣势。这项工作为DPS的缺陷提供了新的见解，并进一步提出了对指标的改进。这项工作的实施可在线获得：https：//github.com/guspih/deep_perceptual_similarity_analysis/

Learning continuous image representations is recently gaining popularity for image super-resolution (SR) because of its ability to reconstruct high-resolution images with arbitrary scales from low-resolution inputs. Existing methods mostly ensemble nearby features to predict the new pixel at any queried coordinate in the SR image. Such a local ensemble suffers from some limitations: i) it has no learnable parameters and it neglects the similarity of the visual features; ii) it has a limited receptive field and cannot ensemble relevant features in a large field which are important in an image; iii) it inherently has a gap with real camera imaging since it only depends on the coordinate. To address these issues, this paper proposes a continuous implicit attention-in-attention network, called CiaoSR. We explicitly design an implicit attention network to learn the ensemble weights for the nearby local features. Furthermore, we embed a scale-aware attention in this implicit attention network to exploit additional non-local information. Extensive experiments on benchmark datasets demonstrate CiaoSR significantly outperforms the existing single image super resolution (SISR) methods with the same backbone. In addition, the proposed method also achieves the state-of-the-art performance on the arbitrary-scale SR task. The effectiveness of the method is also demonstrated on the real-world SR setting. More importantly, CiaoSR can be flexibly integrated into any backbone to improve the SR performance.