3,343 research outputs found
BIQ2021: A Large-Scale Blind Image Quality Assessment Database
The assessment of the perceptual quality of digital images is becoming
increasingly important as a result of the widespread use of digital multimedia
devices. Smartphones and high-speed internet are just two examples of
technologies that have multiplied the amount of multimedia content available.
Thus, obtaining a representative dataset, which is required for objective
quality assessment training, is a significant challenge. The Blind Image
Quality Assessment Database, BIQ2021, is presented in this article. By
selecting images with naturally occurring distortions and reliable labeling,
the dataset addresses the challenge of obtaining representative images for
no-reference image quality assessment. The dataset consists of three sets of
images: those taken without the intention of using them for image quality
assessment, those taken with intentionally introduced natural distortions, and
those taken from an open-source image-sharing platform. It is attempted to
maintain a diverse collection of images from various devices, containing a
variety of different types of objects and varying degrees of foreground and
background information. To obtain reliable scores, these images are
subjectively scored in a laboratory environment using a single stimulus method.
The database contains information about subjective scoring, human subject
statistics, and the standard deviation of each image. The dataset's Mean
Opinion Scores (MOS) make it useful for assessing visual quality. Additionally,
the proposed database is used to evaluate existing blind image quality
assessment approaches, and the scores are analyzed using Pearson and Spearman's
correlation coefficients. The image database and MOS are freely available for
use and benchmarking
Blind Quality Assessment for Image Superresolution Using Deep Two-Stream Convolutional Networks
Numerous image superresolution (SR) algorithms have been proposed for
reconstructing high-resolution (HR) images from input images with lower spatial
resolutions. However, effectively evaluating the perceptual quality of SR
images remains a challenging research problem. In this paper, we propose a
no-reference/blind deep neural network-based SR image quality assessor
(DeepSRQ). To learn more discriminative feature representations of various
distorted SR images, the proposed DeepSRQ is a two-stream convolutional network
including two subcomponents for distorted structure and texture SR images.
Different from traditional image distortions, the artifacts of SR images cause
both image structure and texture quality degradation. Therefore, we choose the
two-stream scheme that captures different properties of SR inputs instead of
directly learning features from one image stream. Considering the human visual
system (HVS) characteristics, the structure stream focuses on extracting
features in structural degradations, while the texture stream focuses on the
change in textural distributions. In addition, to augment the training data and
ensure the category balance, we propose a stride-based adaptive cropping
approach for further improvement. Experimental results on three publicly
available SR image quality databases demonstrate the effectiveness and
generalization ability of our proposed DeepSRQ method compared with
state-of-the-art image quality assessment algorithms
DeepFL-IQA: Weak Supervision for Deep IQA Feature Learning
Multi-level deep-features have been driving state-of-the-art methods for
aesthetics and image quality assessment (IQA). However, most IQA benchmarks are
comprised of artificially distorted images, for which features derived from
ImageNet under-perform. We propose a new IQA dataset and a weakly supervised
feature learning approach to train features more suitable for IQA of
artificially distorted images. The dataset, KADIS-700k, is far more extensive
than similar works, consisting of 140,000 pristine images, 25 distortions
types, totaling 700k distorted versions. Our weakly supervised feature learning
is designed as a multi-task learning type training, using eleven existing
full-reference IQA metrics as proxies for differential mean opinion scores. We
also introduce a benchmark database, KADID-10k, of artificially degraded
images, each subjectively annotated by 30 crowd workers. We make use of our
derived image feature vectors for (no-reference) image quality assessment by
training and testing a shallow regression network on this database and five
other benchmark IQA databases. Our method, termed DeepFL-IQA, performs better
than other feature-based no-reference IQA methods and also better than all
tested full-reference IQA methods on KADID-10k. For the other five benchmark
IQA databases, DeepFL-IQA matches the performance of the best existing
end-to-end deep learning-based methods on average.Comment: dataset url: http://database.mmsp-kn.d
Deep CNN Model for Non-Screen Content and Screen Content Image Quality Assessment
In the current world, user experience in various platforms matters a lot for different organizations. But providing a better experience can be challenging if the multimedia content on online platforms is having different kinds of distortions which impact the overall experience of the user. There can be various reasons behind distortions such as compression or minimal lighting condition while taking photos. In this work, a deep CNN-based Non-Screen Content and Screen Content NR-IQA framework is proposed which solves this issue in a more effective way. The framework is known as DNSSCIQ. Two different architectures are proposed based upon the input image type whether the input is a screen content or non-screen content image. This work attempts to solve this by evaluating the quality of such image
UNIQUE: Unsupervised Image Quality Estimation
In this paper, we estimate perceived image quality using sparse
representations obtained from generic image databases through an unsupervised
learning approach. A color space transformation, a mean subtraction, and a
whitening operation are used to enhance descriptiveness of images by reducing
spatial redundancy; a linear decoder is used to obtain sparse representations;
and a thresholding stage is used to formulate suppression mechanisms in a
visual system. A linear decoder is trained with 7 GB worth of data, which
corresponds to 100,000 8x8 image patches randomly obtained from nearly 1,000
images in the ImageNet 2013 database. A patch-wise training approach is
preferred to maintain local information. The proposed quality estimator UNIQUE
is tested on the LIVE, the Multiply Distorted LIVE, and the TID 2013 databases
and compared with thirteen quality estimators. Experimental results show that
UNIQUE is generally a top performing quality estimator in terms of accuracy,
consistency, linearity, and monotonic behavior.Comment: 12 pages, 5 figures, 2 table
Sparse representation based stereoscopic image quality assessment accounting for perceptual cognitive process
In this paper, we propose a sparse representation based Reduced-Reference Image Quality Assessment (RR-IQA) index for stereoscopic images from the following two perspectives: 1) Human visual system (HVS) always tries to infer the meaningful information and reduces uncertainty from the visual stimuli, and the entropy of primitive (EoP) can well describe this visual cognitive progress when perceiving natural images. 2) Ocular dominance (also known as binocularity) which represents the interaction between two eyes is quantified by the sparse representation coefficients. Inspired by previous research, the perception and understanding of an image is considered as an active inference process determined by the level of “surprise”, which can be described by EoP. Therefore, the primitives learnt from natural images can be utilized to evaluate the visual information by computing entropy. Meanwhile, considering the binocularity in stereo image quality assessment, a feasible way is proposed to characterize this binocular process according to the sparse representation coefficients of each view. Experimental results on LIVE 3D image databases and MCL database further demonstrate that the proposed algorithm achieves high consistency with subjective evaluation
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