- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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A New Image Quality Metric Using Compressive Sensing And A Filter Set Consisting of Derivative And Gabor Filters
摘要： This paper proposes an image quality metric (IQM) using compressive sensing (CS) and a filter set consisting of derivative and Gabor filters. In this paper, compressive sensing that is used for acquiring a sparse or compressible signal with a small number of measurements is used for measuring the quality between the reference and distorted images. However, an image is generally neither sparse nor compressible, so a CS technique cannot be directly used for image quality assessment. Thus, for converting an image into a sparse or compressible signal, the image is convolved with filters such as the gradient, Laplacian of Gaussian, and Gabor filters, since the filter outputs are generally compressible. A small number of measurements obtained by a CS technique are used for evaluating the image quality. Experimental results with various test images show the effectiveness of the proposed algorithm in terms of the Pearson correlation coefficient (CC), root mean squared error, Spearman rank order CC, and Kendall CC.
关键词： Difference Mean Opinion Score,Gabor Filter,Image Quality Assessment,Compressive Sensing,Derivative Filters
更新于2025-09-10 09:29:36
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Evaluation of human observer performance on lesion detectability in single-slice and multislice dedicated breast cone beam CT images with breast anatomical background
摘要： We evaluate the lesion detectability using human and model observer studies in single-slice and multislice cone beam computed tomography (CBCT) images with a breast anatomical background. The purposes of this work are (a) to compare human observer detectability between single-slice and multislice images for different signal sizes and noise structures, (b) to investigate the effect of different multislice viewing modes (i.e., sequential and simultaneous) on the detectability by a human observer, and (c) to predict the detectability by a human observer in single-slice and multislice images using single-slice channelized Hotelling observer (ssCHO) and multislice CHO (msCHO), respectively.
关键词： human observer,model observer,single-slice,image quality,multislice
更新于2025-09-10 09:29:36
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[IEEE 2018 25th IEEE International Conference on Image Processing (ICIP) - Athens, Greece (2018.10.7-2018.10.10)] 2018 25th IEEE International Conference on Image Processing (ICIP) - Automatic ISP Image Quality Tuning Using Nonlinear Optimization
摘要： Image Signal Processor (ISP) comprises of various blocks to reconstruct image sensor raw data to final image consumed by human visual system or computer vision applications. Each block typically has many tuning parameters due to the complexity of the operation. These need to be hand tuned by Image Quality (IQ) experts, which takes considerable amount of time. In this paper, we present an automatic IQ tuning using nonlinear optimization and automatic reference generation algorithms. The proposed method can produce high quality IQ in minutes as compared with weeks of hand-tuned results by IQ experts. In addition, the proposed method can work with any algorithms without being aware of their specific implementation. It was found successful on multiple different processing blocks such as noise reduction, demosaic, and sharpening.
关键词： Image Quality Tuning,ISP,Nonlinear Optimization
更新于2025-09-10 09:29:36
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Contextual Information Based Quality Assessment for Contrast-Changed Images
摘要： In this paper, we propose the objective metric which can precisely predict the perceptual quality of contrast-changed images using inter-pixel contextual information. The metric consists of two parts. One is a 2D histogram-based contrast quality measure which utilizes the distribution of the gray-level differences between adjacent pixels. We design the desired 2D histogram considering the characteristic of an adequately high contrast image, and predict contrast quality by comparing the desired 2D histogram with 2D histograms of an original image and a contrast-changed image. The other is a spatial entropy based one which uses the information of spatial location distribution of gray-levels. A comparison is carried out with many IQA metrics on five contrast related databases. Experimental results show that the proposed metric provides a more accurate prediction of human perception of contrast change than other metrics.
关键词： 2D histogram and spatial entropy,Image quality assessment (IQA),contrast-changed images
更新于2025-09-10 09:29:36
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[IEEE 2018 40th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC) - Honolulu, HI, USA (2018.7.18-2018.7.21)] 2018 40th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC) - Coherence Plane-Wave Compounding with Angle Coherence Factor for Ultrafast Ultrasound Imaging
摘要： Ultrafast ultrasound imaging with plane wave transmission has been a promising technique to image moving objects, however, implies compromises among resolution, contrast and sensitivity. Coherence plane-wave compounding (CPWC) can balance the image quality and frame rate. The image quality, especially in terms of the suppression of artifacts stemmed from side lobes, is greatly comprised by reducing the number of the tilted plane-waves. However, in some special scenarios, such as tracking shear wave propagation inside soft tissue, and imaging the complex blood flow, it’s better to keep a very high frame rate. How to realize a B-mode image of equivalent quality to the standard focused approach at a very high frame rate? Here we proposed a new imaging framework by combining CPWC with angle coherence factor. The B-mode images from simulation, experimental phantoms demonstrated that our proposed methodology greatly suppressed the side-lobes artifacts by around 20 dB compared with CPWC imaging, while the image quality, especially lateral resolution and contrast kept equivalent.
关键词： image quality,side-lobes artifacts,coherence-based factor,coherence plane-wave compounding
更新于2025-09-10 09:29:36
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Stereoscopic Image Quality Assessment by Deep Convolutional Neural Network
摘要： In this paper, we propose a no-reference (NR) quality assessment method for stereoscopic images by deep convolutional neural network (DCNN). Inspired by the internal generative mechanism (IGM) in the human brain, which shows that the brain first analyzes the perceptual information and then extract effective visual information. Meanwhile, in order to simulate the inner interaction process in the human visual system (HVS) when perceiving the visual quality of stereoscopic images, we construct a two-channel DCNN to evaluate the visual quality of stereoscopic images. First, we design a Siamese Network to extract high-level semantic features of left- and right-view images for simulating the process of information extraction in the brain. Second, to imitate the information interaction process in the HVS, we combine the high-level features of left- and right-view images by convolutional operations. Finally, the information after interactive processing is used to estimate the visual quality of stereoscopic image. Experimental results show that the proposed method can estimate the visual quality of stereoscopic images accurately, which also demonstrate the effectiveness of the proposed two-channel convolutional neural network in simulating the perception mechanism in the HVS.
关键词： convolutional neural network,Image quality assessment,no reference,stereoscopic images
更新于2025-09-10 09:29:36
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Assessment of image quality and radiation dose in some models of digital radiography systems?–?A Pehamed FLUORAD A?+?D phantom study
摘要： Digital radiography (DR) systems have been recently introduced as a developed technology that is replacing conventional film–screen systems in many countries around the world. Ideal situation in radiography is to maximize the image quality while minimizing the patient dose. The purpose of this study was to compare image quality and radiation dose in different digital radiography systems. Four different digital systems are compared in terms of their image quality performance and dose area product (DAP). Images of Pehamed FLUORAD A + D phantom were obtained for each DR system. Image quality parameters (contrast resolution (CR), spatial resolution (SR), and contrast-to-noise ratio (CNR)) and DAP were significantly different between different digital systems. It was shown that all four quantities increased with increasing exposure parameters in all systems. Image quality parameters of the SEDECAL system were higher than that in other systems (p ≤ 0.05). At the stable DAP (100 mGy.cm2), means of CR, CNR, and SR in the SEDECAL system were 6.38 ± 0.797, 29.70 ± 0.85 and 3.10 ± 0.38 lp/mm, respectively. The results of this investigation can be taken into consideration in the selection and purchasing of new systems in order to preserve patients as well as radiographers from unnecessary radiation dose.
关键词： image quality,digital radiology,phantom,dosimetry
更新于2025-09-10 09:29:36
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Unified No-Reference Quality Assessment of Singly and Multiply Distorted Stereoscopic Images
摘要： A challenging problem in no-reference quality assessment of multiply distorted stereoscopic images (MDSIs) is to simulate the monocular and binocular visual properties under a mixed type of distortions. Due to the joint effects of multiple distortions in MDSIs, the underlying monocular and binocular visual mechanisms have different manifestations with those of singly distorted stereoscopic images (SDSIs). This paper presents a unified no-reference quality evaluator for SDSIs and MDSIs by learning monocular and binocular local visual primitives (MB-LVPs). The main idea is to learn MB-LVPs to characterize the local receptive field properties of the visual cortex in response to SDSIs and MDSIs. Furthermore, we also consider that the learning of primitives should be performed in a task-driven manner. For this, two penalty terms including reconstruction error and quality inconsistency are jointly minimized within a supervised dictionary learning framework, generating a set of quality-oriented MB-LVPs for each single and multiple distortion modality. Given an input stereoscopic image, feature encoding is performed using the learned MB-LVPs as codebooks, resulting in the corresponding monocular and binocular responses. Finally, responses across all the modalities are fused with probabilistic weights which are determined by the modality-specific sparse reconstruction errors, yielding the final monocular and binocular features for quality regression. The superiority of our method has been verified on several SDSI and MDSI databases.
关键词： multiply distorted,singly distorted,receptive field,monocular and binocular vision,stereoscopic image,local visual primitive,No-reference image quality assessment
更新于2025-09-09 09:28:46
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Potential of the Reverse Synthesis Method for the High-Quality SAR Image Synthesis
摘要： A potential of a new Reverse synthesis method proposed at IGARSS 2017 for the high-quality Synthetic Aperture Radar (SAR) image synthesis is presented. Images produced by the method are compared with the best existing approaches for the speckle noise reduction. Further capabilities for the image quality improvement like side lobe, range and azimuth reduction, contrast improvement, autofocusing and target detectability improvement are considered. The novel approach allows both: to produce high quality and high-resolution images from existing SAR raw data and to create new high-quality systems with reduced demands to the on-board equipment.
关键词： SAR,speckle noise,image synthesis,high resolution,synthetic aperture radar,synthetic aperture imaging,image quality
更新于2025-09-09 09:28:46
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[IEEE 2017 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC) - Atlanta, GA (2017.10.21-2017.10.28)] 2017 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC) - SPECT Reconstruction and Analysis for the Inspection of Spent Nuclear Fuel
摘要： A gamma-emission-tomography (GET) system for the inspection of spent nuclear fuel (SNF) has been developed and tested on multiple fuel types. This tool can be used for verification of the integrity of an assembly and consistency with fissile-material content. Parallel-beam line integrals are measured by a discrete array of CdZnTe detectors that view the fuel through a 1.5mm wide by 100mm thick tungsten collimator. Detectors and electronics are on a rotating platform within a watertight stainless steel torus. During operation, the system is underwater and fuel is lowered through the center of the torus and held stationary as data are collected. Tomographic data collection requires a time on the order of minutes. In field experiments, data with count rates in the range of 50kcps to >500kcps per pixel have been recorded. In the reconstructed images, missing or replaced pins in all assembly types can be visually discriminated in the lattice of fuel pins. Automated detection of missing/replaced pins is the metric used for determination of optimal processing steps. Effectiveness of reconstruction and data-processing tools is measured by a tools ability to improve performance on the pin-discrimination task. This paper describes the data preprocessing, image reconstruction, image analysis, and performance evaluation of this system.
关键词： gamma-ray emission tomography,image quality metrics,safeguards,attenuation correction,image reconstruction,spent nuclear fuel
更新于2025-09-09 09:28:46