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Artykuły w czasopismach na temat "Subjective and Objective Image Quality Assessment"
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Park, Hyung-ju, i Dong-hwan Har. "Subjective image quality assessment based on objective image quality measurement factors". IEEE Transactions on Consumer Electronics 57, nr 3 (sierpień 2011): 1176–84. http://dx.doi.org/10.1109/tce.2011.6018872.
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Afnan, Afnan, Faiz Ullah, Yaseen Yaseen, Jinhee Lee, Sonain Jamil i Oh-Jin Kwon. "Subjective Assessment of Objective Image Quality Metrics Range Guaranteeing Visually Lossless Compression". Sensors 23, nr 3 (23.01.2023): 1297. http://dx.doi.org/10.3390/s23031297.
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The usage of media such as images and videos has been extensively increased in recent years. It has become impractical to store images and videos acquired by camera sensors in their raw form due to their huge storage size. Generally, image data is compressed with a compression algorithm and then stored or transmitted to another platform. Thus, image compression helps to reduce the storage size and transmission cost of the images and videos. However, image compression might cause visual artifacts, depending on the compression level. In this regard, performance evaluation of the compression algorithms is an essential task needed to reconstruct images with visually or near-visually lossless quality in case of lossy compression. The performance of the compression algorithms is assessed by both subjective and objective image quality assessment (IQA) methodologies. In this paper, subjective and objective IQA methods are integrated to evaluate the range of the image quality metrics (IQMs) values that guarantee the visually or near-visually lossless compression performed by the JPEG 1 standard (ISO/IEC 10918). A novel “Flicker Test Software” is developed for conducting the proposed subjective and objective evaluation study. In the flicker test, the selected test images are subjectively analyzed by subjects at different compression levels. The IQMs are calculated at the previous compression level, when the images were visually lossless for each subject. The results analysis shows that the objective IQMs with more closely packed values having the least standard deviation that guaranteed the visually lossless compression of the images with JPEG 1 are the feature similarity index measure (FSIM), the multiscale structural similarity index measure (MS-SSIM), and the information content weighted SSIM (IW-SSIM), with average values of 0.9997, 0.9970, and 0.9970 respectively.
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Zhang, Huiqing, Donghao Li, Yibing Yu i Nan Guo. "Subjective and Objective Quality Assessments of Display Products". Entropy 23, nr 7 (26.06.2021): 814. http://dx.doi.org/10.3390/e23070814.
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In recent years, people’s daily lives have become inseparable from a variety of electronic devices, especially mobile phones, which have undoubtedly become necessity in people’s daily lives. In this paper, we are looking for a reliable way to acquire visual quality of the display product so that we can improve the user’s experience with the display product. This paper proposes two major contributions: the first one is the establishment of a new subjective assessment database (DPQAD) of display products’ screen images. Specifically, we invited 57 inexperienced observers to rate 150 screen images showing the display product. At the same time, in order to improve the reliability of screen display quality score, we combined the single stimulation method with the stimulation comparison method to evaluate the newly created display products’ screen images database effectively. The second one is the development of a new no-reference image quality assessment (IQA) metric. For a given image of the display product, first our method extracts 27 features by analyzing the contrast, sharpness, brightness, etc., and then uses the regression module to obtain the visual quality score. Comprehensive experiments show that our method can evaluate natural scene images and screen content images at the same time. Moreover, compared with ten state-of-the-art IQA methods, our method shows obvious superiority on DPQAD.
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Zhang, Chun E., Fan Ci Guo i Ke Xiong. "Towards Subjective Consistency: An Effective Objective Quality Assessment Algorithm for Binary Image". Key Engineering Materials 474-476 (kwiecień 2011): 143–50. http://dx.doi.org/10.4028/www.scientific.net/kem.474-476.143.
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Image quality assessment plays an important role in various image processing applications. One of the challenges to objectively assess image quality is how to design an effective scheme to achieve high consistency with the classic subjective image assessment criterion, Mean Opinion Score (MOS). This work presents a novel objective assessment algorithm for binary images by considering three factors which have great influences on visual quality of binary images, i.e., structural change caused by noise point, isolated noise points, and gathering noise points. Experimental results show that our algorithm can achieve effective objective assessment results with higher consistency with the MOS criterion.
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Zelmati, Omar, Boban Bondžulić, Boban Pavlović, Ivan Tot i Saad Merrouche. "Study of subjective and objective quality assessment of infrared compressed images". Journal of Electrical Engineering 73, nr 2 (1.04.2022): 73–87. http://dx.doi.org/10.2478/jee-2022-0011.
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Abstract Given the lack of accessible infrared compressed images’ benchmarks annotated by human subjects, this work presents a new database with the aim of studying both subjective and objective image quality assessment (IQA) on compressed long wavelength infrared (LWIR) images. The database contains 20 reference (pristine) images and 200 distorted (degraded) images obtained by application of the most known compression algorithms used in multimedia and communication fields, namely: JPEG and JPEG-2000. Each compressed image is evaluated by 31 subjects having different levels of experience in LWIR images. Mean opinion scores (MOS) and natural scene statistics (NSS) of pristine and compressed images are elaborated to study the performance of the database. Five analyses are conducted on collected images and subjective scores, namely: analysis by compression type, analysis by file size, analysis by reference image, analysis by quality level and analysis by subject. Moreover, a wide set of objective IQA metrics is applied on the images and the obtained scores are compared with the collected subjective scores. Results show that objective IQA measures correlate with human subjective results with a degree of agreement up to 95 %, so this benchmark is promising to improve existing and develop new IQA measures for compressed LWIR images. Thanks to a real-world surveillance original images based on which we analyze how image compression and quality level affect the quality of compressed images, this database is primarily suitable for (military and civilian) surveillance applications. The database is accessible via the link: https://github.com/azedomar/compressed-LWIR-images-IQA-database. As a follow-up to this work, an extension of the database is underway to study other types of distortion in addition to compression.
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Park, Hyung-Ju, i Dong-Hwan Har. "Correlation Research between Objective and Subjective Image Quality Assessment". Journal of the Korea Contents Association 11, nr 8 (28.08.2011): 68–76. http://dx.doi.org/10.5392/jkca.2011.11.8.068.
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Shrestha, Prarthana, Rik Kneepkens, Gijs van Elswijk, Jeroen Vrijnsen, Roxana Ion, Dirk Verhagen, Esther Abels, Dirk Vossen i and Bas Hulsken. "Objective and Subjective Assessment of Digital Pathology Image Quality". AIMS Medical Science 2, nr 1 (2015): 65–78. http://dx.doi.org/10.3934/medsci.2015.1.65.
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Good, Walter F., David Gur, John H. Feist, F. Leland Thaete, Carl R. Fuhrman, Cynthia A. Britton i B. Simon Slasky. "Subjective and objective assessment of image quality—A comparison". Journal of Digital Imaging 7, nr 2 (maj 1994): 77–78. http://dx.doi.org/10.1007/bf03168426.
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Oszust, Mariusz. "No-Reference Image Quality Assessment with Local Gradient Orientations". Symmetry 11, nr 1 (16.01.2019): 95. http://dx.doi.org/10.3390/sym11010095.
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Image processing methods often introduce distortions, which affect the way an image is subjectively perceived by a human observer. To avoid inconvenient subjective tests in cases in which reference images are not available, it is desirable to develop an automatic no-reference image quality assessment (NR-IQA) technique. In this paper, a novel NR-IQA technique is proposed in which the distributions of local gradient orientations in image regions of different sizes are used to characterize an image. To evaluate the objective quality of an image, its luminance and chrominance channels are processed, as well as their high-order derivatives. Finally, statistics of used perceptual features are mapped to subjective scores by the support vector regression (SVR) technique. The extensive experimental evaluation on six popular IQA benchmark datasets reveals that the proposed technique is highly correlated with subjective scores and outperforms related state-of-the-art hand-crafted and deep learning approaches.
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Yang, Yang, Jun Ming i Nenghai Yu. "Color Image Quality Assessment Based on CIEDE2000". Advances in Multimedia 2012 (2012): 1–6. http://dx.doi.org/10.1155/2012/273723.
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Combining the color difference formula of CIEDE2000 and the printing industry standard for visual verification, we present an objective color image quality assessment method correlated with subjective vision perception. An objective score conformed to subjective perception (OSCSP)Qwas proposed to directly reflect the subjective visual perception. In addition, we present a general method to calibrate correction factors of color difference formula under real experimental conditions. Our experiment results show that the present DE2000-based metric can be consistent with human visual system in general application environment.
Rozprawy doktorskie na temat "Subjective and Objective Image Quality Assessment"
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Sendjasni, Abderrezzaq. "Objective and subjective quality assessment of 360-degree images". Electronic Thesis or Diss., Poitiers, 2023. http://www.theses.fr/2023POIT2251.
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Les images à 360 degrés, aussi appelées images omnidirectionnelles, sont au cœur des contenus immersifs. Avec l’augmentation de leur utilisation notamment grâce à l’expérience interactive et immersive qu’ils offrent, il est primordial de garantir une bonne qualité d’expérience (QoE). Cette dernière est considérablement impactée par la qualité du contenu lui-même. En l’occurrence, les images à 360 degrés, comme tout type de signal visuel, passent par une séquence de processus comprenant l’encodage, la transmission, le décodage et le rendu. Chacun de ces processus est susceptible d’introduire des distorsions dans le contenu. Pour améliorer la qualité d’expérience, toutes ces dégradations potentielles doivent être soigneusement prises en compte et réduites à un niveau imperceptible. Pour atteindre cet objectif, l’évaluation de la qualité de l’image est l’une des stratégies devant être utilisée. Cette thèse aborde l’évaluation de la qualité des images à 360 degrés des points de vue objectif et subjectif. Ainsi, en s’intéressant à l’effet des visiocasques sur la qualité perçue des images 360 degrés, une étude psycho-visuelle est conçue et réalisée en utilisant quatre dispositifs différents. À cette fin, une base de données a été créé et un panel d’observateurs a été impliqué. L’impact des visiocasques sur la qualité a été identifié et mis en évidence comme un facteur important à prendre en compte lors de la réalisation d’expériences subjectives pour des images à 360 degrés. D’un point de vue objectif, nous avons d’abord procédé à une étude comparative extensive de plusieurs modèles de réseaux de neurones convolutifs (CNN) sous diverses configurations. Ensuite, nous avons amélioré la chaîne de traitement de l’évaluation de la qualité basée sur les CNN à différentes échelles, de l’échantillonnage et de la représentation des entrées à l’agrégation des scores de qualité. En se basant sur les résultats de ces études, et de l’analyse comparative, deux modèles de qualité basés sur les CNN sont proposés pour prédire avec précision la qualité des images à 360 degrés. Les observations et les conclusions obtenues à partir des différentes contributions de cette thèse apporteront un éclairage sur l’évaluation de la qualité des images à 360 degrés360-degree images, a.k.a. omnidirectional images, are in the center of immersive media. With the increase in demands of the latter, mainly thanks to the offered interactive and immersive experience, it is paramount to provide good quality of experience (QoE). This QoE is significantly impacted by the quality of the content. Like any type of visual signal, 360-degree images go through a sequence of processes including encoding, transmission, decoding, and rendering. Each of these processes has the potential to introduce distortions to the content. To improve the QoE, image quality assessment (IQA) is one of the strategies to be followed. This thesis addresses the quality evaluation of 360-degree images from the objective and subjective perspectives. By focusing on the influence of Head Mounted Displays (HMDs) on the perceived quality of 360-degree images, a psycho-visual study is designed and carried out using four different devices. For this purpose, a 360-degree image datasets is created and a panel of observers is involved. The impact of HMDs on the quality ratings is identified and highlighted as an important factor to consider when con- ducting subjective experiments for 360-degree images. From the objective perspective, we first comprehensively benchmarked several convolutional neural network (CNN) models under various configurations. Then, the processing chain of CNN-based 360-IQA is improved at different scales, from input sampling and representation to aggregating quality scores. Based on the observations of the above studies as well as the benchmark, two 360-IQA models based on CNNs are proposed to accurately predict the quality of 360-degree images. The obtained observations and conclusions from the various contributions shall bring insights for assessing the quality of 360-degree images
360-graders bilder, også kjent som rundstrålende bilder, er i sentrum av oppslukende medier. Med økningen i forventninger til sistnevnte, hovedsakelig takket være den aktiverte interaktive og oppslukende opplevelse, er det avgjørende å gi god kvaliteten på opplevelsen (QoE).Denne QoE er betydelig påvirket av kvaliteten på innholdet. Som alle typer visuelle signaler går 360-graders bilder gjennom en sekvens av prosesser, inkludert koding, overføring, dekoding og gjengivelse. Hver av disse prosessene har potensial til å introdusere forvrengninger til innholdet.For å forbedre QoE er vurdering av bildekvalitet (IQA) en av strategiene å følge. Denne oppgaven tar for seg kvalitetsevaluering av 360-graders bilder fra objektive og subjektive perspektiver. Ved å fokusere på påvirkningen av Head Mounted Displays (HMD-er) på den oppfattede kvaliteten til 360-graders bilder, er en psyko-visuell studie designet og utført ved hjelp av fire forskjellige enheter. For dette formålet opprettes et 360-graders bildedatasett og et panel av observatører er involvert. Virkningen av HMD-er på valitetsvurderingene identifiseres og fremheves som en viktig faktor når du utfører subjektive eksperimenter for 360-graders bilder.Fra det objektive perspektivet benchmarket vi først flere konvolusjonelle nevrale nettverk (CNN) under forskjellige konfigurasjoner. Deretter forbedres prosesseringskjeden til CNN-baserte 360-IQA i forskjellige skalaer, fra input-sampling og representasjon til aggregering av kvalitetspoeng. Basert på observasjonene av de ovenfornevnte studiene så vel som benchmark, foreslås to 360-IQA-modeller basert på CNN-er for å nøyaktig forutsi kvaliteten på 360-graders bilder.De innhentede observasjonene og konklusjonene fra de ulike bidragene skal gi innsikt for å vurdere kvaliteten på 360-graders bilder
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Zerman, Emin. "Evaluation et analyse de la qualité vidéo à haute gamme dynamique". Electronic Thesis or Diss., Paris, ENST, 2018. http://www.theses.fr/2018ENST0003.
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Au cours de la dernière décennie, la technologie de l’image et de la vidéo à haute gamme dynamique (High dynamic range - HDR) a attiré beaucoup d’attention, en particulier dans la communauté multimédia. Les progrés technologiques récents ont facilité l’acquisition, la compression et la reproduction du contenu HDR, ce qui a mené à la commercialisation des écrans HDR et à la popularisation du contenu HDR. Dans ce contexte, la mesure de la qualité du contenu HDR joue un rôle fondamental dans l’amélioration de la chaîne de distribution du contenu ainsi que des opérations qui la composent, telles que la compression et l’affichage. Cependant, l’évaluation de la qualité visuelle HDR présente de nouveaux défis par rapport au contenu à gamme dynamique standard (Standard dynamic range -SDR). Le premier défi concerne les nouvelles conditions introduites par la reproduction du contenu HDR, par ex. l’augmentation de la luminosité et du contraste. Même si une reproduction exacte de la luminance d’une scène n’est pas nécessaire pour la plupart des cas pratiques, une estimation précise de la luminance émise est cependant nécessaire pour les mesures d’évaluation objectives de la qualité HDR. Afin de comprendre les effets du rendu d’affichage sur la perception de la qualité, un algorithme permettant de reproduire très précisement une image HDR a été développé et une expérience subjective a été menée pour analyser l’impact de différents rendus sur l’évaluation subjective et objective de la qualité HDR. En outre, afin de comprendre l’impact de la couleur avec la luminosité accrue des écrans HDR, les effets des différents espaces de couleurs sur les performances de compression vidéo HDR ont également été analysés dans une autre étude subjective. Un autre défi consiste à estimer objectivement la qualité du contenu HDR, en utilisant des ordinateurs et des algorithmes. Afin de relever ce défi, la thèse procède à l’évaluation des performances des métriques de qualité d’image HDR avec référence (Full reference-FR). Les images HDR ont une plus grande plage de luminosité et des valeurs de contraste plus élevées. Etant donné que la plupart des métriques de qualité d’image sont développées pour les images SDR, elles doivent être adaptées afin d’estimer la qualité des images HDR. Différentes méthodes d’adaptation ont été utilisées pour les mesures SDR, et elles ont été comparées avec les métriques de qualité d’image existantes développées exclusivement pour les images HDR. De plus, nous proposons une nouvelle méthode d’évaluation des métriques objectives basée sur une nouvelle approche de classification. Enfin, nous comparons les scores de qualité subjectifs acquis en utilisant différentes méthodologies de test subjectives. L’évaluation subjective de la qualité est considérée comme le moyen le plus efficace et le plus fiable d’obtenir des scores de qualité «vérité-terrain» pour les stimuli sélectionnés, et les scores moyens d’opinion (Mean opinion scores-MOS) obtenus sont les valeurs auxquelles les métriques objectives sont entraînées pour correspondre. En fait, de fortes divergences peuvent facilement être rencontrés lorsque différentes bases de données de qualité multimédia sont considérées. Afin de comprendre la relation entre les valeurs de qualité acquises à l’aide de différentes méthodologies, la relation entre les valeurs MOS et les résultats des comparaisons par paires rééchellonés (Pairwise comparisons - PC) a été comparée. A cette fin, une série d’expériences ont été menées entre les méthodologies double stimulus impairment scale (DSIS) et des comparaisons par paires. Nous proposons d’inclure des comparaisons inter-contenu dans les expériences PC afin d’améliorer les performances de rééchelonnement et de réduire la variance inter-contenu ainsi que les intervalles de confiance. Les scores de PC rééchellonés peuvent également être utilisés pour des scénarios subjectifs d’évaluation de la qualité multimédia autres que le HDRIn the last decade, high dynamic range (HDR) image and video technology gained a lot of attention, especially within the multimedia community. Recent technological advancements made the acquisition, compression, and reproduction of HDR content easier, and that led to the commercialization of HDR displays and popularization of HDR content. In this context, measuring the quality of HDR content plays a fundamental role in improving the content distribution chain as well as individual parts of it, such as compression and display. However, HDR visual quality assessment presents new challenges with respect to the standard dynamic range (SDR) case. The first challenge is the new conditions introduced by the reproduction of HDR content, e.g. the increase in brightness and contrast. Even though accurate reproduction is not necessary for most of the practical cases, accurate estimation of the emitted luminance is necessary for the objective HDR quality assessment metrics. In order to understand the effects of display rendering on the quality perception, an accurate HDR frame reproduction algorithm was developed, and a subjective experiment was conducted to analyze the impact of different display renderings on subjective and objective HDR quality evaluation. Additionally, in order to understand the impact of color with the increased brightness of the HDR displays, the effects of different color spaces on the HDR video compression performance were also analyzed in another subjective study. Another challenge is to estimate the quality of HDR content objectively, using computers and algorithms. In order to address this challenge, the thesis proceeds with the performance evaluation of full-reference (FR) HDR image quality metrics. HDR images have a larger brightness range and higher contrast values. Since most of the image quality metrics are developed for SDR images, they need to be adapted in order to estimate the quality of HDR images. Different adaptation methods were used for SDR metrics, and they were compared with the existing image quality metrics developed exclusively for HDR images. Moreover, we propose a new method for the evaluation of metric discriminability based ona novel classification approach. Motivated by the need to fuse several different quality databases, in the third part of the thesis, we compare subjective quality scores acquired by using different subjective test methodologies. Subjective quality assessment is regarded as the most effective and reliable way of obtaining “ground-truth” quality scores for the selected stimuli, and the obtained mean opinion scores (MOS) are the values to which generally objective metrics are trained to match. In fact, strong discrepancies can easily be notified across databases when different multimedia quality databases are considered. In order to understand the relationship between the quality values acquired using different methodologies, the relationship between MOS values and pairwise comparisons (PC) scaling results were compared. For this purpose, a series of experiments were conducted using double stimulus impairment scale (DSIS) and pairwise comparisons subjective methodologies. We propose to include cross-content comparisons in the PC experiments in order to improve scaling performance and reduce cross-content variance as well as confidence intervals. The scaled PC scores can also be used for subjective multimedia quality assessment scenarios other than HDR
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Ševčík, Martin. "Modelování vlastností modelu HVS v Matlabu". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217656.
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In theoretical part Diploma thesis deals with the model of human vision HVS (Human Visual System), which can be used for image quality assessment in TV technique area. It has been described calculations of selected JND (Just Noticeable Difference) metrics, used in evaluation of HVS. In practical part of the thesis it has been suggested and realized simulation model in Matlab, which may be used for evaluation of three JND metrics from color and grayscale images and evaluation in spatial a frequency domain. Results of JND models have been compared to another objective image quality evaluation metrics (MSE, NMSE, SNR and PSNR). For interpretation of dependencies it has been used images with different defined content.
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Dalasari, Venkata Gopi Krishna, i Sri Krishna Jayanty. "Low Light Video Enhancement along with Objective and Subjective Quality Assessment". Thesis, Blekinge Tekniska Högskola, Institutionen för tillämpad signalbehandling, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-13500.
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Enhancing low light videos has been quite a challenge over the years. A video taken in low light always has the issues of low dynamic range and high noise. This master thesis presents contribution within the field of low light video enhancement. Three models are proposed with different tone mapping algorithms for extremely low light low quality video enhancement. For temporal noise removal, a motion compensated kalman structure is presented. Dynamic range of the low light video is stretched using three different methods. In Model 1, dynamic range is increased by adjustment of RGB histograms using gamma correction with a modified version of adaptive clipping thresholds. In Model 2, a shape preserving dynamic range stretch of the RGB histogram is applied using SMQT. In Model 3, contrast enhancement is done using CLAHE. In the final stage, the residual noise is removed using an efficient NLM. The performance of the models are compared on various Objective VQA metrics like NIQE, GCF and SSIM. To evaluate the actual performance of the models subjective tests are conducted, due to the large number of applications that target humans as the end user of the video.The performance of the three models are compared for a total of ten real time input videos taken in extremely low light environment. A total of 25 human observers subjectively evaluated the performance of the three models based on the parameters: contrast, visibility, visually pleasing, amount of noise and overall quality. A detailed statistical evaluation of the relative performance of the three models is also provided.
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Guo, Jinjiang. "Contributions to objective and subjective visual quality assessment of 3d models". Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEI099.
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Dans le domaine de l’informatique graphique, les données tridimensionnelles, généralement représentées par des maillages triangulaires, sont employées dans une grande variété d’applications (par exemple, le lissage, la compression, le remaillage, la simplification, le rendu, etc.). Cependant, ces procédés introduisent inévitablement des artefacts qui altèrent la qualité visuelle des données 3D rendues. Ainsi, afin de guider perceptuellement les algorithmes de traitement, il y a un besoin croissant d'évaluations subjectives et objectives de la qualité visuelle à la fois performantes et adaptées, pour évaluer et prédire les artefacts visuels. Dans cette thèse, nous présentons d'abord une étude exhaustive sur les différentes sources d'artefacts associés aux données numériques graphiques, ainsi que l’évaluation objective et subjective de la qualité visuelle des artefacts. Ensuite, nous introduisons une nouvelle étude sur la qualité subjective conçue sur la base de l’évaluations de la visibilité locale des artefacts géométriques, dans laquelle il a été demandé à des observateurs de marquer les zones de maillages 3D qui contiennent des distorsions visibles. Les cartes de distorsion visuelle collectées sont utilisées pour illustrer plusieurs fonctionnalités perceptuelles du système visuel humain (HVS), et servent de vérité-terrain pour évaluer les performances des attributs et des mesures géométriques bien connus pour prédire la visibilité locale des distorsions. Notre deuxième étude vise à évaluer la qualité visuelle de modèles 3D texturés, subjectivement et objectivement. Pour atteindre ces objectifs, nous avons introduit 136 modèles traités avec à la fois des distorsions géométriques et de texture, mené une expérience subjective de comparaison par paires, et invité 101 sujets pour évaluer les qualités visuelles des modèles à travers deux protocoles de rendu. Motivés par les opinions subjectives collectées, nous proposons deux mesures de qualité visuelle objective pour les maillages texturés, en se fondant sur les combinaisons optimales des mesures de qualité issues de la géométrie et de la texture. Ces mesures de perception proposées surpassent leurs homologues en termes de corrélation avec le jugement humainIn computer graphics realm, three-dimensional graphical data, generally represented by triangular meshes, have become commonplace, and are deployed in a variety of application processes (e.g., smoothing, compression, remeshing, simplification, rendering, etc.). However, these processes inevitably introduce artifacts, altering the visual quality of the rendered 3D data. Thus, in order to perceptually drive the processing algorithms, there is an increasing need for efficient and effective subjective and objective visual quality assessments to evaluate and predict the visual artifacts. In this thesis, we first present a comprehensive survey on different sources of artifacts in digital graphics, and current objective and subjective visual quality assessments of the artifacts. Then, we introduce a newly designed subjective quality study based on evaluations of the local visibility of geometric artifacts, in which observers were asked to mark areas of 3D meshes that contain noticeable distortions. The collected perceived distortion maps are used to illustrate several perceptual functionalities of the human visual system (HVS), and serve as ground-truth to evaluate the performances of well-known geometric attributes and metrics for predicting the local visibility of distortions. Our second study aims to evaluate the visual quality of texture mapped 3D model subjectively and objectively. To achieve these goals, we introduced 136 processed models with both geometric and texture distortions, conducted a paired-comparison subjective experiment, and invited 101 subjects to evaluate the visual qualities of the models under two rendering protocols. Driven by the collected subjective opinions, we propose two objective visual quality metrics for textured meshes, relying on the optimal combinations of geometry and texture quality measures. These proposed perceptual metrics outperform their counterparts in term of the correlation with the human judgment
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Shahid, Muhammad. "Methods for Objective and Subjective Video Quality Assessment and for Speech Enhancement". Doctoral thesis, Blekinge Tekniska Högskola [bth.se], Faculty of Engineering - Department of Applied Signal Processing, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-00603.
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The overwhelming trend of the usage of multimedia services has raised the consumers' awareness about quality. Both service providers and consumers are interested in the delivered level of perceptual quality. The perceptual quality of an original video signal can get degraded due to compression and due to its transmission over a lossy network. Video quality assessment (VQA) has to be performed in order to gauge the level of video quality. Generally, it can be performed by following subjective methods, where a panel of humans judges the quality of video, or by using objective methods, where a computational model yields an estimate of the quality. Objective methods and specifically No-Reference (NR) or Reduced-Reference (RR) methods are preferable because they are practical for implementation in real-time scenarios. This doctoral thesis begins with a review of existing approaches proposed in the area of NR image and video quality assessment. In the review, recently proposed methods of visual quality assessment are classified into three categories. This is followed by the chapters related to the description of studies on the development of NR and RR methods as well as on conducting subjective experiments of VQA. In the case of NR methods, the required features are extracted from the coded bitstream of a video, and in the case of RR methods additional pixel-based information is used. Specifically, NR methods are developed with the help of suitable techniques of regression using artificial neural networks and least-squares support vector machines. Subsequently, in a later study, linear regression techniques are used to elaborate the interpretability of NR and RR models with respect to the selection of perceptually significant features. The presented studies on subjective experiments are performed using laboratory based and crowdsourcing platforms. In the laboratory based experiments, the focus has been on using standardized methods in order to generate datasets that can be used to validate objective methods of VQA. The subjective experiments performed through crowdsourcing relate to the investigation of non-standard methods in order to determine perceptual preference of various adaptation scenarios in the context of adaptive streaming of high-definition videos. Lastly, the use of adaptive gain equalizer in the modulation frequency domain for speech enhancement has been examined. To this end, two methods of demodulating speech signals namely spectral center of gravity carrier estimation and convex optimization have been studied.
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Khaustova, Darya. "Objective assessment of stereoscopic video quality of 3DTV". Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S021/document.
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Le niveau d'exigence minimum pour tout système 3D (images stéréoscopiques) est de garantir le confort visuel des utilisateurs. Le confort visuel est un des trois axes perceptuels de la qualité d'expérience (QoE) 3D qui peut être directement lié aux paramètres techniques du système 3D. Par conséquent, le but de cette thèse est de caractériser objectivement l'impact de ces paramètres sur la perception humaine afin de contrôler la qualité stéréoscopique. La première partie de la thèse examine l'intérêt de prendre en compte l'attention visuelle des spectateurs dans la conception d'une mesure objective de qualité 3D. Premièrement, l'attention visuelle en 2D et 3D sont comparées en utilisant des stimuli simples. Les conclusions de cette première expérience sont validées en utilisant des scènes complexes avec des disparités croisées et décroisées. De plus, nous explorons l'impact de l'inconfort visuel causé par des disparités excessives sur l'attention visuelle. La seconde partie de la thèse est dédiée à la conception d'un modèle objectif de QoE pour des vidéos 3D, basé sur les seuils perceptuels humains et le niveau d'acceptabilité. De plus nous explorons la possibilité d'utiliser la modèle proposé comme une nouvelle échelle subjective. Pour la validation de ce modèle, des expériences subjectives sont conduites présentant aux sujets des images stéréoscopiques fixes et animées avec différents niveaux d'asymétrie. La performance est évaluée en comparant des prédictions objectives avec des notes subjectives pour différents niveaux d'asymétrie qui pourraient provoquer un inconfort visuelThe minimum requirement for any 3D (stereoscopic images) system is to guarantee visual comfort of viewers. Visual comfort is one of the three primary perceptual attributes of 3D QoE, which can be linked directly with technical parameters of a 3D system. Therefore, the goal of this thesis is to characterize objectively the impact of these parameters on human perception for stereoscopic quality monitoring. The first part of the thesis investigates whether visual attention of the viewers should be considered when designing an objective 3D quality metrics. First, the visual attention in 2D and 3D is compared using simple test patterns. The conclusions of this first experiment are validated using complex stimuli with crossed and uncrossed disparities. In addition, we explore the impact of visual discomfort caused by excessive disparities on visual attention. The second part of the thesis is dedicated to the design of an objective model of 3D video QoE, which is based on human perceptual thresholds and acceptability level. Additionally we explore the possibility to use the proposed model as a new subjective scale. For the validation of proposed model, subjective experiments with fully controlled still and moving stereoscopic images with different types of view asymmetries are conducted. The performance is evaluated by comparing objective predictions with subjective scores for various levels of view discrepancies which might provoke visual discomfort
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Sahu, Amit K. "Objective assessment of image quality (OAIQ) in fluorescence-enhanced optical imaging". [College Station, Tex. : Texas A&M University, 2006. http://hdl.handle.net/1969.1/ETD-TAMU-1068.
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Chintala, Bala Venkata Sai Sundeep. "Objective Perceptual Quality Assessment of JPEG2000 Image Coding Format Over Wireless Channel". Thesis, Blekinge Tekniska Högskola, Institutionen för tillämpad signalbehandling, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-17785.
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A dominant source of Internet traffic, today, is constituted of compressed images. In modern multimedia communications, image compression plays an important role. Some of the image compression standards set by the Joint Photographic Expert Group (JPEG) include JPEG and JPEG2000. The expert group came up with the JPEG image compression standard so that still pictures could be compressed to be sent over an e-mail, be displayed on a webpage, and make high-resolution digital photography possible. This standard was originally based on a mathematical method, used to convert a sequence of data to the frequency domain, called the Discrete Cosine Transform (DCT). In the year 2000, however, a new standard was proposed by the expert group which came to be known as JPEG2000. The difference between the two is that the latter is capable of providing better compression efficiency. There is also a downside to this new format introduced. The computation required for achieving the same sort of compression efficiency as one would get with the original JPEG format is higher. JPEG is a lossy compression standard which can throw away some less important information without causing any noticeable perception differences. Whereas, in lossless compression, the primary purpose is to reduce the number of bits required to represent the original image samples without any loss of information. The areas of application of the JPEG image compression standard include the Internet, digital cameras, printing, and scanning peripherals. In this thesis work, a simulator kind of functionality setup is needed for conducting the objective quality assessment. An image is given as an input to our wireless communication system and its data size is varied (e.g. 5%, 10%, 15%, etc) and a Signal-to-Noise Ratio (SNR) value is given as input, for JPEG2000 compression. Then, this compressed image is passed through a JPEG encoder and then transmitted over a Rayleigh fading channel. The corresponding image obtained after having applied these constraints on the original image is then decoded at the receiver and inverse discrete wavelet transform (IDWT) is applied to inverse the JPEG 2000 compression. Quantization is done for the coefficients which are scalar-quantized to reduce the number of bits to represent them, without the loss of quality of the image. Then the final image is displayed on the screen. The original input image is co-passed with the images of varying data size for an SNR value at the receiver after decoding. In particular, objective perceptual quality assessment through Structural Similarity (SSIM) index using MATLAB is provided.
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Reilly, Andrew James. "Uniform framework for the objective assessment and optimisation of radiotherapy image quality". Thesis, University of Edinburgh, 2011. http://hdl.handle.net/1842/5589.
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Image guidance has rapidly become central to current radiotherapy practice. A uniform framework is developed for evaluating image quality across all imaging modalities by modelling the ‘universal phantom’: breaking any phantom down into its constituent fundamental test objects and applying appropriate analysis techniques to these through the construction of an automated analysis tree. This is implemented practically through the new software package ‘IQWorks’ and is applicable to both radiotherapy and diagnostic imaging. For electronic portal imaging (EPI), excellent agreement was observed with two commercial solutions: the QC-3V phantom and PIPS Pro software (Standard Imaging) and EPID QC phantom and epidSoft software (PTW). However, PIPS Pro’s noise correction strategy appears unnecessary for all but the highest frequency modulation transfer function (MTF) point and its contrast to noise ratio (CNR) calculation is not as described. Serious flaws identified in epid- Soft included erroneous file handling leading to incorrect MTF and signal to noise ratio (SNR) results, and a sensitivity to phantom alignment resulting in overestimation of MTF points by up to 150% for alignment errors of only ±1 pixel. The ‘QEPI1’ is introduced as a new EPI performance phantom. Being a simple lead square with a central square hole it is inexpensive and straightforward to manufacture yet enables calculation of a wide range of performance metrics at multiple locations across the field of view. Measured MTF curves agree with those of traditional bar pattern phantoms to within the limits of experimental uncertainty. An intercomparison of the Varian aS1000 and aS500-II detectors demonstrated an improvement in MTF for the aS1000 of 50–100% over the clinically relevant range 0.4–1 cycles/mm, yet with a corresponding reduction in CNR by a factor of p 2. Both detectors therefore offer advantages for different clinical applications. Characterisation of cone-beam CT (CBCT) facilities on two Varian On-Board Imaging (OBI) units revealed that only two out of six clinical modes had been calibrated by default, leading to errors of the order of 400 HU for some modes and materials – well outside the ±40 HU tolerance. Following calibration, all curves agreed sufficiently for dose calculation accuracy within 2%. CNR and MTF experiments demonstrated that a boost in MTF f50 of 20–30% is achievable by using a 5122 rather than a 3842 matrix, but with a reduction in CNR of the order of 30%. The MTF f50 of the single-pulse half-resolution radiographic mode of the Varian PaxScan 4030CB detector was measured in the plane of the detector as 1.0±0.1 cycles/mm using both a traditional tungsten edge and the new QEPI1 phantom. For digitally reconstructed radiographs (DRRs), a reduction in CT slice thickness resulted in an expected improvement in MTF in the patient scanning direction but a deterioration in the orthogonal direction, with the optimum slice thickness being 1–2 mm. Two general purposes display devices were calibrated against the DICOM Greyscale Standard Display Function (GSDF) to within the ±20% limit for Class 2 review devices. By providing an approach to image quality evaluation that is uniform across all radiotherapy imaging modalities this work enables consistent end-to-end optimisation of this fundamental part of the radiotherapy process, thereby supporting enhanced use of image-guidance at all relevant stages of radiotherapy and better supporting the clinical decisions based on it.
Książki na temat "Subjective and Objective Image Quality Assessment"
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Lorsakul, Auranuch. Objective Assessment of Image Quality: Extension of Numerical Observer Models to Multidimensional Medical Imaging Studies. [New York, N.Y.?]: [publisher not identified], 2015.
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Sicari, Rosa, Edyta Płońska-Gościniak i Jorge Lowenstein. Stress echocardiography: image acquisition and modalities. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780198726012.003.0013.
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Stress echocardiography has evolved over the last 30 years but image interpretation remains subjective and burdened by the operator’s experience. The objective operator-independent assessment of myocardial ischaemia during stress echocardiography remains a technological challenge. Still, adequate quality of two-dimensional images remains a prerequisite to successful quantitative analysis, even using Doppler and non-Doppler based techniques. No new technology has proved to have a higher diagnostic accuracy than conventional visual wall motion analysis. Tissue Doppler imaging and derivatives may reduce inter-observer variability, but still require a dedicated learning curve and special expertise. The development of contrast media in echocardiography has been slow. In the past decade, transpulmonary contrast agents have become commercially available for clinical use. The approved indication for the use of contrast echocardiography currently lies in improving endocardial border delineation in patients in whom adequate imaging is difficult or suboptimal. Real-time three-dimensional echocardiography is potentially useful but limited by low spatial and temporal resolution. It is possible that these technologies may serve as an adjunct to expert visual assessment of wall motion. At present, these quantitative methods require further validation and simplification of analysis techniques.
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Carrión, Victor G., John A. Turner i Carl F. Weems. Sleep. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780190201968.003.0005.
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The architecture of healthy sleep rests upon a network of several interacting neurochemical systems, an arrangement that is easily disrupted by the experience of traumatic stress. As a result, sleep may be among the most susceptible of behaviors to have a negative impact as a result of trauma. Sleep disturbances, or “parasomnias,” such as nightmares, sleepwalking, and insomnia are one of the most prominent hallmarks of PTSD, and the study of these sleep-specific symptoms can provide a window into the underlying pathology of the disorder. The current chapter reviews the preclinical animal literature that has informed our understanding of the brain structures that are involved in the development of these parasomnias. In reviewing adult and child studies of disrupted sleep in PTSD, a distinction is made between the subjective and objective assessment of sleep quality, with a call made for an emphasis on objective measurements in future research.
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Williams, Jerry R. Diagnostic radiology equipment. Oxford University Press, 2015. http://dx.doi.org/10.1093/med/9780199655212.003.0012.
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The chapter is concerned with the features of radiographic and fluoroscopic equipment that present radiation protection issues for both patients and staff. These are managed through regulation, manufacturing standards, and adherence to safe working practices. It is different for patients who are deliberately irradiated in accordance with justification protocols not considered here. Radiation protection is based on the ALARP principle which requires the resultant dose to be minimized consistent with image quality is sufficient to provide accurate and safe diagnosis. Dose minimization is critically dependent on detector efficiency. Quality control of dose for individual examinations is particularly important to provide assurance of ALARP. It should include not only patient dose assessment but also detector dose indicators, particularly in radiography. These issues are discussed in detail together with other dose-saving features and discussion on objective methods of image quality assessment. Commissioning and lifetime tests are required for quality assurance programmes. These are described.
Części książek na temat "Subjective and Objective Image Quality Assessment"
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Barkowsky, Marcus, Kjell Brunnström, Touradj Ebrahimi, Lina Karam, Pierre Lebreton, Patrick Le Callet, Andrew Perkis i in. "Subjective and Objective Visual Quality Assessment in the Context of Stereoscopic 3D-TV". W 3D-TV System with Depth-Image-Based Rendering, 413–37. New York, NY: Springer New York, 2012. http://dx.doi.org/10.1007/978-1-4419-9964-1_14.
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Kowalik-Urbaniak, Ilona A., Jane Castelli, Nasim Hemmati, David Koff, Nadine Smolarski-Koff, Edward R. Vrscay, Jiheng Wang i Zhou Wang. "Modelling of Subjective Radiological Assessments with Objective Image Quality Measures of Brain and Body CT Images". W Lecture Notes in Computer Science, 3–13. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-20801-5_1.
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Cheeseman, Alison K., Ilona A. Kowalik-Urbaniak i Edward R. Vrscay. "Objective Image Quality Measures of Degradation in Compressed Natural Images and their Comparison with Subjective Assessments". W Lecture Notes in Computer Science, 163–72. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-41501-7_19.
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Lewandowska, Anna. "Subjective Image Quality Assessment Optimization". W Advances in Intelligent Systems and Computing, 171–78. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-47274-4_20.
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Pramerdorfer, Christopher, i Martin Kampel. "Deep Objective Image Quality Assessment". W Computer Analysis of Images and Patterns, 127–38. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-64698-5_12.
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Ding, Yong. "Subjective Ratings and Image Quality Databases". W Visual Quality Assessment for Natural and Medical Image, 5–25. Berlin, Heidelberg: Springer Berlin Heidelberg, 2018. http://dx.doi.org/10.1007/978-3-662-56497-4_2.
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Xu, Jiahua, Chaoyi Lin, Wei Zhou i Zhibo Chen. "Subjective Quality Assessment of Stereoscopic Omnidirectional Image". W Advances in Multimedia Information Processing – PCM 2018, 589–99. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-030-00776-8_54.
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Landre, Victor, Marius Pedersen i Dag Waaler. "Memory Effects in Subjective Quality Assessment of X-Ray Images". W Image Analysis, 314–25. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-59129-2_27.
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Zhang, Changjiang, Juan Lu i Jinshan Wang. "Objective Quality Assessment Measurement for Typhoon Cloud Image Enhancement". W Image Analysis and Processing – ICIAP 2009, 767–76. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-04146-4_82.
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Koumaras, Harilaos G. "Objective and Subjective Assessment Methods of Video Quality in Multimedia Broadcasting". W Mobile Multimedia Broadcasting Standards, 417–34. Boston, MA: Springer US, 2009. http://dx.doi.org/10.1007/978-0-387-78263-8_14.
Pełny tekst źródłaStreszczenia konferencji na temat "Subjective and Objective Image Quality Assessment"
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Queluz, Maria Paula, Francisco Lopes, João Ascenso i António Rodrigues. "Subjective and objective quality assessment of omnidirectional video". W Applications of Digital Image Processing XLI, redaktor Andrew G. Tescher. SPIE, 2018. http://dx.doi.org/10.1117/12.2321679.
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Bhargava, Chitresh, i Nidhi Verma. "Improved subjective and objective image quality assessment of JPEG image". W 2014 International Conference on Information Communication and Embedded Systems (ICICES). IEEE, 2014. http://dx.doi.org/10.1109/icices.2014.7033994.
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Hou, Limin, Weiqi Wu, Shuang Yang, Tao Yang i Xinpeng Zhang. "Subjective and objective quality assessment of re-sampling audio". W 2012 International Conference on Audio, Language and Image Processing (ICALIP). IEEE, 2012. http://dx.doi.org/10.1109/icalip.2012.6376634.
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Gu, Ke, Guangtao Zhai, Xiaokang Yang, Wenjun Zhang i Min Liu. "Subjective and objective quality assessment for images with contrast change". W 2013 20th IEEE International Conference on Image Processing (ICIP). IEEE, 2013. http://dx.doi.org/10.1109/icip.2013.6738079.
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Wang, Xu, Lei Cao, Yingying Zhu, Yun Zhang, Jianmin Jiang i Sam Kwong. "Study of subjective and objective quality assessment for screen content images". W 2017 IEEE International Conference on Image Processing (ICIP). IEEE, 2017. http://dx.doi.org/10.1109/icip.2017.8296381.
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Trioux, Anthony, Giuseppe Valenzise, Marco Cagnazzo, Michel Kieffer, Francois-Xavier Coudoux, Patrick Corlay i Mohamed Gharbi. "Subjective and Objective Quality Assessment of the SoftCast Video Transmission Scheme". W 2020 IEEE International Conference on Visual Communications and Image Processing (VCIP). IEEE, 2020. http://dx.doi.org/10.1109/vcip49819.2020.9301778.
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Chaabouni, A., Y. Gaudeau, J. Lambert, J. M. Moureaux i P. Gallet. "Subjective and objective quality assessment for H264 compressed medical video sequences". W 2014 4th International Conference on Image Processing Theory, Tools and Applications (IPTA). IEEE, 2014. http://dx.doi.org/10.1109/ipta.2014.7001922.
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Wang, Anyang, Guangtao Zhai, Yuanchun Chen, Zhaohui Che i Xiaokang Yang. "Subjective and objective quality assessment for color changed images". W 2017 IEEE International Symposium on Broadband Multimedia Systems and Broadcasting (BMSB). IEEE, 2017. http://dx.doi.org/10.1109/bmsb.2017.7986169.
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Chen, Qi, Fang Liu, Huiyu Duan, Yao Wang, Xiongkuo Min, Yan Zhou i Guangtao Zhai. "MRIQA: Subjective Method and Objective Model for Magnetic Resonance Image Quality Assessment". W 2022 IEEE International Conference on Visual Communications and Image Processing (VCIP). IEEE, 2022. http://dx.doi.org/10.1109/vcip56404.2022.10008885.
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Ebenezer, Joshua P., Yixu Chen, Yongjun Wu, Hai Wei i Sriram Sethuraman. "Subjective and Objective Quality Assessment of High-Motion Sports Videos at Low-Bitrates". W 2022 IEEE International Conference on Image Processing (ICIP). IEEE, 2022. http://dx.doi.org/10.1109/icip46576.2022.9897837.
Pełny tekst źródłaRaporty organizacyjne na temat "Subjective and Objective Image Quality Assessment"
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Mizrach, Amos, Sydney L. Spahr, Ephraim Maltz, Michael R. Murphy, Zeev Schmilovitch, Jan E. Novakofski, Uri M. Peiper i in. Ultrasonic Body Condition Measurements for Computerized Dairy Management Systems. United States Department of Agriculture, 1993. http://dx.doi.org/10.32747/1993.7568109.bard.
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The body condition (BC) score is recognized in the dairy industry as an essential tool for managing the energy reserves of the dairy cow, which is essential for sustaining optimal and efficient production over several lactations. The current use of BC scoring depends on the accuracy of subjective visual estimates, and this limits its kusefulness as a management aid in the dairy industry. A measuring tool that would frequently provide objective data on the cow's body reserves would be a major contribution to efficient dairy herd management. Ultrasonic sensors have the potential to be developed into an efficient BC measuring device, and the experimental use of such sensors for subcutaneous fat thickness (SDFT) estimates, as an indication for BC in beef cattle, supports this assumption. The purposes of this project were: 1. To compare visual BC scoring and ultrasonic fat thickness with on-line automated body weight (BW) measurements as monitors of nutritional adequacy of dairy cows at various stages of lactation. 2. To determine the effects of variation in digestive fill in early and late lactation on the accuracy of body weight measurements in lactating cows. 3. To modify an existing ultrasonic system and develop a specialized, low-cost sensor for repeatable determination of body condition scores by users with minimal training and skill. 4. To develop a standard for the assignment of body condition scores based on ultrasonic measurements of subdermal fat thickness. The procedure to execute these objectives involved: 1. Frequent measurement of BW, milk yield (MY), BC (visually scored) and subdermal fat thickness ultrasonically measured of dairy cows, and data analysis on average and individual basis. 2. Testing and selection of an appropriate special-purpose sensor, finding an optimum body location for working an ultrasonic measurement, prcessing the signals obtained, and correlating the resulting measurements with performance responses in lactating cows. Linking the ultrasonic signals to BC scores, and developing a BC scoring data acquisition system are the first steps towards fulfilling the necessary requirements for incorporating this device into an existing dairy herd management system, in order to provide the industry with a powerful managment tool. From the results obtained we could conclude that: 1. BC does not correlate with BW changes during all stages of lactation, although in general terms it does. These results were confirmed by individual cow BW and BC data obtained during the course of lactation, that were supported by individual objective ultrasonic measurement of SDFT. 2. BW changes reflect energy metabolism reliably ony after peak milk yield; early in lactation, a decrease in BW expresses mobilization of body reserves only qualitatively, and not quantitatively. 3. Gastrointestinal content increases throughout the whole period during which dry matter intake (DMI) increases. The drastic increase very early in lactation prevents the use of BW changes as a basis for quantitative estimatio of energy meatabolism; at this stage of lactation, konly a BC score or any other direct measurements willl provide a quantitative estimate of energy metabolism. 4. Ultrasonic measurements of subdermal fat thickness can be used to quantify changes that correlate with the actual condition of the cow, as assessed by performance and the traditional way of scoring. 5. To find the best site on the cow's body at which to obtain responses to BC and its changes in the course of lactation, additional sites have to be examined. From the present study, it seems that the sites between ribs 12 and 13 have the potential for this purpose. 6. The use of templates made it easier to repeat measurements at a desired site and spot. However, the convenient easy-to-handle way to standardize the measurement, described in this study, koffers scope for improvement. 7. The RF peak values of the A-mode are better indicators of the location of fat layer borders than image analysis, from the point of view of future commercial development. 8. The distances between the RF peaks of the A-mode can be automatically measured by suitable software, for future commercial development. 9. Proper analysis of daily body weight and milk yield data can provide the necessary information on body condition changes during lactation, until a direct BC measurement device is developed. 10. In any case, at least one visual BC assessment has to be done, preferably immediately after calving, for calibration purposes.