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Perceptual quality metrics applied to still image compression

Michael P. Eckert, Andrew P. Bradley
1998 Signal Processing  
We present a review of perceptual image quality metrics and their application to still image compression.  ...  The review describes how image quality metrics can be used to guide an image compression scheme and outlines the advantages, disadvantages, and limitations of a number of quality metrics.  ...  lack of masking at high frequencies.  ... 
doi:10.1016/s0165-1684(98)00124-8 fatcat:crp65kdcvna43bncmi6ytsverq

Quality assessment methods for perceptual video compression

Fan Zhang, David R. Bull
2013 2013 IEEE International Conference on Image Processing  
This paper describes a quality assessment model for perceptual video compression applications (PVM), which stimulates visual masking and distortion-artefact perception using an adaptive combination of  ...  noticeable distortions and blurring artefacts.  ...  The maximum of all six high frequency DT-CWT subband coefficient magnitudes at the first level of decomposition are used to form a spatial mask.  ... 
doi:10.1109/icip.2013.6738009 dblp:conf/icip/ZhangB13 fatcat:nu7luh3csbcttbegnrpnqby4ua

Crop Detection through Blocking Artefacts Analysis [chapter]

A. R. Bruna, G. Messina, S. Battiato
2011 Lecture Notes in Computer Science  
In this paper we propose a new method to detect cropped images by analyzing the blocking artefacts produced by a previous block based compression techniques such as JPEG and MPEG family that are the most  ...  used compression standards for still images and video sequences.  ...  Results of the visualization of the Fourier spectrum applied to the compressed Lena image shown in Figure 2 Fig. 5 . 5 Fig. 5. Sobel filter masks Fig. 6 . 6 Fig. 6.  ... 
doi:10.1007/978-3-642-24085-0_66 fatcat:j643ubi7b5f5nlgpexzlxrydpi

Extended IMD2020: a large‐scale annotated dataset tailored for detecting manipulated images

Adam Novozámský, Babak Mahdian, Stanislav Saic
2021 IET Biometrics  
The real versions of these images are also provided. We also manually created binary masks localising the exact manipulated areas of these images.  ...  Image forensic datasets need to accommodate a complex diversity of systematic noise and intrinsic image artefacts to prevent any overfitting of learning methods to a small set of camera types or manipulation  ...  A range of compression levels brings a range of quantization noise into the visual content. Different manipulation techniques yield different editing traces.  ... 
doi:10.1049/bme2.12025 fatcat:6mfzldsyrjee5jx3wk4c44zj5q

Two-stream Encoder-Decoder Network for Localizing Image Forgeries [article]

Aniruddha Mazumdar, Prabin Kumar Bora
2020 arXiv   pre-print
This is motivated from the fact that the forgery creation process generally introduces both the high-level artefacts (e.g. unnatural contrast) and the low-level artefacts (e.g. noise inconsistency) to  ...  In the second stream, the encoder learns the high-level image manipulation features from the input image RGB values.  ...  A perfectly curated forged image looks visually plausible; Nevertheless, the forgery creation process introduces various high-level and low-level artefacts in the forged image.  ... 
arXiv:2009.12881v1 fatcat:cfxwonggibe2rds5crcl2x3fie

A disocclusion replacement approach to subjective assessment for depth map quality evaluation

N. Haddad, S. Dogan, H. Kodikara Arachchi, V. De Silva, A.M. Kondoz
2014 2014 3DTV-Conference: The True Vision - Capture, Transmission and Display of 3D Video (3DTV-CON)  
The videos and images rendered using the highly compressed depth maps, (i.e. depth maps compressed by setting a high QP value: namely QP32 and QP42), have been generally penalised by the observers.  ...  The compression mode was set to a constant QP to maintain a consistent level of quantization errors.  ... 
doi:10.1109/3dtv.2014.6874733 dblp:conf/3dtv/HaddadDASK14 fatcat:bk6pmfhehvbldckplzq52ejlrm

Quality Assessment in Computer Graphics [chapter]

Guillaume Lavoué, Rafał Mantiuk
2014 Visual Signal Quality Assessment  
This broad area of research includes many subdomains which make intensive use of quality assessment and/or artefact visibility evaluation: geometry processing, rendering, HDR imaging, tone mapping and  ...  We broadly classify these existing works into image-based (i.e. evaluating artefacts introduced in 2D rendered images and videos) and model-based approaches (i.e. artefacts introduced on the 3D models  ...  The visual difference predictors can be further weighted by a saliency map, which accounts for low-level attention [31, 73] and/or task-driven high-level attention [14] .  ... 
doi:10.1007/978-3-319-10368-6_9 fatcat:zo4fksfnk5fctkpyvbqaeg3mg4

Visual Distortion Assessment With Emphasis on Spatially Transitional Regions

E. Ong, W. Lin, Z. Lu, S. Yao, M. Etoh
2004 IEEE transactions on circuits and systems for video technology (Print)  
For decompressed images or video, the spatially transitional regions are the regions where major perceptually disturbing artefacts caused by edge impairments (mainly due to blurring and locations where  ...  In this paper, we combine a perceptual model with an integrated detection of the spatially transitional regions in visual distortion evaluation to better match the HVS perception to visual quality.  ...  disturbing artefacts (namely, edge impairment and the presence of false edges) in decoded images.  ... 
doi:10.1109/tcsvt.2004.825574 fatcat:l435vejqd5cv7hcoqpienrucxu

HistoQC: An Open-Source Quality Control Tool for Digital Pathology Slides

Andrew Janowczyk, Ren Zuo, Hannah Gilmore, Michael Feldman, Anant Madabhushi
2019 JCO Clinical Cancer Informatics  
One of the challenges in DP is the presence of artefacts and batch effects, unintentionally introduced during both routine slide preparation (eg, staining, tissue folding) and digitization (eg, blurriness  ...  Therefore, there is a critical need for a reproducible automated approach of precisely localizing artefacts to identify slides that need to be reproduced or regions that should be avoided during computational  ...  For example, due to the heterogeneity in compression levels typically present between DP scanners and the evidence that the resulting compression artefacts affect performance of deep-learning and AI algorithms  ... 
doi:10.1200/cci.18.00157 pmid:30990737 pmcid:PMC6552675 fatcat:ybqczomdrzgszc3sqcl2nk55u4

Image compression using sparse colour sampling combined with nonlinear image processing

Stephen Brooks, Ian Saunders, Neil A. Dodgson, Bernice E. Rogowitz, Thrasyvoulos N. Pappas, Scott J. Daly
2007 Human Vision and Electronic Imaging XII  
Our investigations were to ascertain whether their mechanisms could be used to improve the image compression rate for the same level of visual quality.  ...  Neither algorithm was designed for image compression.  ...  Figure 2 shows a comparison of typical artefacts at high levels of compression.  ... 
doi:10.1117/12.703056 dblp:conf/hvei/BrooksSD07 fatcat:rvbrvqbdnbebrpsfj37c7wrgdm

Perceptual Quality Metric for H.264 Low Bit Rate Videos

Ee Ong, Weisi Lin, Zhongkang Lu, Susu Yao, Mei Loke
2006 2006 IEEE International Conference on Multimedia and Expo  
In this paper, computational models have been applied to emulate human visual perception based on a combination of local and global modulating factors.  ...  This paper proposed an objective video quality metric designed for automatically assessing the perceived quality of digitally compressed multimedia videos using H.264 video compression.  ...  Masking is a very important visual phenomenon which explains why similar artefacts are disturbing in certain regions of an image frame while they are hardly noticeable in other regions.  ... 
doi:10.1109/icme.2006.262536 dblp:conf/icmcs/OngLLYL06 fatcat:dcm6kplyzvb7rdqk5wilnisc2m

RESTORATION TECHNIQUE FOR PLEIADES-HR PANCHROMATIC IMAGES

C. Latry, S. Fourest, C. Thiebaut
2012 The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
level target for denoised images, wavelet packet decomposition level.  ...  Raw images are thus blurry which implies a deconvolution stage that restores sharpness but also increases the noise level in the high frequency domain.  ...  ACKNOWLEDGEMENTS The author would like to thank the whole team of image experts who have performed a great job, spending time, energy and enthusiasm during the 6 month of the image quality commissioning  ... 
doi:10.5194/isprsarchives-xxxix-b1-555-2012 fatcat:ckvdoz5ky5eaxlwtfv56toh53m

Object based Image Splicing Localization using Block Artificial Grids

P N R L Chandra Sekhar, T N
2020 International Journal of Advanced Computer Science and Applications  
In contrast to existing approaches, the proposed approach extracts the artefacts on individual objects instead of the entire image.  ...  This paper proposes an efficient statistical method based on Block Artificial Grids in double compressed images to identify regions attacked by image manipulation.  ...  The networks extract high-level visual features and neglect low-level features, which can be sources for forensic cues.  ... 
doi:10.14569/ijacsa.2020.0111164 fatcat:g2j4tc3x5nbvjgmwl2pkjwmjfq

Non-Semantic Evaluation of Image Forensics Tools: Methodology and Database [article]

Quentin Bammey
2021 arXiv   pre-print
With the aim of evaluating image forensics tools, we propose a methodology to create forgeries traces, leaving intact the semantics of the image.  ...  Thus, the only forgery cues left are the specific alterations of one or several aspects of the image formation pipeline.  ...  In particular, CFA-based methods are notoriously weak on JPEG images, since JPEG compression removes the high frequencies, in which mosaic artefacts lie.  ... 
arXiv:2105.02700v1 fatcat:34woyuwk2veqnaeuggvqyulmta

Subjective Image Fidelity Assessment: Effect of the Spatial Distance Between Stimuli

Steven Le Moan, Marius Pedersen
2019 2019 IEEE International Conference on Image Processing (ICIP)  
Our results further highlight the role of memory in subjective quality assessment and visual masking.  ...  We designed and carried out a study to compare quality assessment for two different levels of reliance on visual short-term memory.  ...  Therefore, our results further demonstrate the effect of high-level masking in image fidelity assessment.  ... 
doi:10.1109/icip.2019.8802953 dblp:conf/icip/MoanP19 fatcat:6qdxn2lwqnhtnoakkkqo4f7obm
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