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IEEE Transactions on Pattern Analysis... Sep 2023Image editing and compositing have become ubiquitous in entertainment, from digital art to AR and VR experiences. To produce beautiful composites, the camera needs to be...
Image editing and compositing have become ubiquitous in entertainment, from digital art to AR and VR experiences. To produce beautiful composites, the camera needs to be geometrically calibrated, which can be tedious and requires a physical calibration target. In place of the traditional multi-image calibration process, we propose to infer the camera calibration parameters such as pitch, roll, field of view, and lens distortion directly from a single image using a deep convolutional neural network. We train this network using automatically generated samples from a large-scale panorama dataset, yielding competitive accuracy in terms of standard l error. However, we argue that minimizing such standard error metrics might not be optimal for many applications. In this work, we investigate human sensitivity to inaccuracies in geometric camera calibration. To this end, we conduct a large-scale human perception study where we ask participants to judge the realism of 3D objects composited with correct and biased camera calibration parameters. Based on this study, we develop a new perceptual measure for camera calibration and demonstrate that our deep calibration network outperforms previous single-image based calibration methods both on standard metrics as well as on this novel perceptual measure. Finally, we demonstrate the use of our calibration network for several applications, including virtual object insertion, image retrieval, and compositing.
PubMed: 37195850
DOI: 10.1109/TPAMI.2023.3269641 -
Applied Neuropsychology. Adult Apr 2023There are many commonalities between the clinical symptoms of dementia with Lewy bodies (DLB) and those of Alzheimer's disease (AD). The accurate differentiation of...
There are many commonalities between the clinical symptoms of dementia with Lewy bodies (DLB) and those of Alzheimer's disease (AD). The accurate differentiation of these two diseases is an important neuropsychological issue. The Mini-Mental State Examination (MMSE) is often used as a screening test for dementing disorders. We created evaluation items for the pentagon copy test of MMSE and developed a simple, highly accurate evaluation method for differentiating DLB in combination with conventional evaluation items such as the Qualitative Scoring MMSE Pentagon Test (QSPT). Subjects were divided into three groups: DLB (n = 119), AD (n = 50), and Normal (n = 26). The severities of DLB and AD ranged from mild cognitive impairment (MCI) to mild dementia. We compared the results of the pentagon copy test. We found that the rates of patients with abnormalities in "motor incoordination" and "gestalt destruction" were higher in the DLB group than the AD group. Furthermore, receiver operating characteristic curve analysis suggested the differentiation of DLB with high accuracy (sensitivity: 0.70, specificity: 0.78) using the criterion of patients meeting one of the following three characteristics: "the number of angles on QSPT: scores other than 4," "major tremor (Parkinsonism-related tremor) is present," and "gestalt destruction (distortion in overall coherence) is present." This evaluation method may be clinically useful for evaluating MCI to mild DLB patients because the burden on patients is low.
PubMed: 37052204
DOI: 10.1080/23279095.2023.2200948 -
IEEE Transactions on Image Processing :... Mar 2023With the increasing demand of compressing and streaming 3D point clouds under constrained bandwidth, it has become ever more important to accurately and efficiently...
With the increasing demand of compressing and streaming 3D point clouds under constrained bandwidth, it has become ever more important to accurately and efficiently determine the quality of compressed point clouds, so as to assess and optimize the quality-of-experience (QoE) of end users. Here we make one of the first attempts developing a bitstream-based no-reference (NR) model for perceptual quality assessment of point clouds without resorting to full decoding of the compressed data stream. Specifically, we first establish a relationship between texture complexity and the bitrate and texture quantization parameters based on an empirical rate-distortion model. We then construct a texture distortion assessment model upon texture complexity and quantization parameters. By combining this texture distortion model with a geometric distortion model derived from Trisoup geometry encoding parameters, we obtain an overall bitstream-based NR point cloud quality model named streamPCQ. Experimental results show that the proposed streamPCQ model demonstrates highly competitive performance when compared with existing classic full-reference (FR) and reduced-reference (RR) point cloud quality assessment methods with a fraction of computational cost.
PubMed: 37028320
DOI: 10.1109/TIP.2023.3253252 -
Journal of Experimental Psychology.... Aug 2023Maintaining perceptual experiences in visual working memory (VWM) allows us to flexibly accomplish various tasks, but some tasks come at a price. For example, comparing...
Maintaining perceptual experiences in visual working memory (VWM) allows us to flexibly accomplish various tasks, but some tasks come at a price. For example, comparing VWM representations to novel perceptual inputs can induce inadvertent memory distortions. If these distortions can persist, they may explain why everyday memories often become unreliable after people perform perceptual comparisons (e.g., eyewitness testimony). Here, we conducted two experiments to assess the consequences of perceptual comparisons using real-world objects that were temporarily maintained in VWM ( = 32) or recalled from visual long-term memory back into VWM ( = 30). In each experiment, young adults reported systematic memory distortions following perceptual comparisons. These distortions increased in magnitude with the delay between encoding and comparisons and were preserved when memories were retrieved again a day later. These findings suggest that perceptual comparisons play a mechanistic role in everyday memory distortions, including situations where memory accuracy is vital. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
Topics: Young Adult; Humans; Memory, Short-Term; Mental Recall; Memory, Long-Term; Visual Perception
PubMed: 36951741
DOI: 10.1037/xge0001400 -
Computers in Biology and Medicine May 2023Image fusion techniques have been widely used for multi-modal medical image fusion tasks. Most existing methods aim to improve the overall quality of the fused image and...
Image fusion techniques have been widely used for multi-modal medical image fusion tasks. Most existing methods aim to improve the overall quality of the fused image and do not focus on the more important textural details and contrast between the tissues of the lesion in the regions of interest (ROIs). This can lead to the distortion of important tumor ROIs information and thus limits the applicability of the fused images in clinical practice. To improve the fusion quality of ROIs relevant to medical implications, we propose a multi-modal MRI fusion generative adversarial network (BTMF-GAN) for the task of multi-modal MRI fusion of brain tumors. Unlike existing deep learning approaches which focus on improving the global quality of the fused image, the proposed BTMF-GAN aims to achieve a balance between tissue details and structural contrasts in brain tumor, which is the region of interest crucial to many medical applications. Specifically, we employ a generator with a U-shaped nested structure and residual U-blocks (RSU) to enhance multi-scale feature extraction. To enhance and recalibrate features of the encoder, the multi-perceptual field adaptive transformer feature enhancement module (MRF-ATFE) is used between the encoder and the decoder instead of a skip connection. To increase contrast between tumor tissues of the fused image, a mask-part block is introduced to fragment the source image and the fused image, based on which, we propose a novel salient loss function. Qualitative and quantitative analysis of the results on the public and clinical datasets demonstrate the superiority of the proposed approach to many other commonly used fusion methods.
Topics: Humans; Brain Neoplasms; Magnetic Resonance Imaging; Image Processing, Computer-Assisted
PubMed: 36947904
DOI: 10.1016/j.compbiomed.2023.106769 -
Aesthetic Surgery Journal Jul 2023Lip filler enhancement has fast become one of the most popular minimally invasive cosmetic procedures. Motivations for "overtreatment" with lip fillers are poorly...
BACKGROUND
Lip filler enhancement has fast become one of the most popular minimally invasive cosmetic procedures. Motivations for "overtreatment" with lip fillers are poorly understood.
OBJECTIVES
The aim of this study was to explore female motivations for and experiences of procedures that achieve an aesthetic of distorted lip anatomy.
METHODS
Twenty-four females who had undergone lip filler procedures resulting in strikingly distorted lip anatomy, determined by the Harris classification of filler spread, took part in semistructured interviews about their motivations, experiences, and perceptions related to lip fillers. A qualitative thematic analysis was carried out.
RESULTS
Four major themes are discussed: (1) the normalization of lip fillers, (2) perceptual drift which is mediated by exposure to repetitive images of larger lips on social media, (3) perceived financial and social benefits of larger lips, and (4) the relation between mental health and seeking repeated lip filler procedures.
CONCLUSIONS
Motivations for seeking lip fillers vary, but most subjects described social media impacting perceived aesthetic norms. A process of perceptual drift occurs whereby mental schema encoding expectations of "natural" facial anatomy can adapt through repeated exposure to enhanced images. The results can inform aesthetic practitioners and policymakers seeking to understand and support those seeking minimally invasive cosmetic procedures.
Topics: Adult; Humans; Female; Motivation; Beauty; Cosmetic Techniques; Lip; Face; Dermal Fillers; Hyaluronic Acid
PubMed: 36879449
DOI: 10.1093/asj/sjad050 -
Frontiers in Sports and Active Living 2023
PubMed: 36814895
DOI: 10.3389/fspor.2023.1138516 -
Cerebellum (London, England) Apr 2024Ataxia-telangiectasia (A-T) is a disease caused by mutations in the ATM gene (11q22.3-23.1) that induce neurodegeneration Sasihuseyinoglu AS et al. Pediatr Allergy... (Observational Study)
Observational Study
Ataxia-telangiectasia (A-T) is a disease caused by mutations in the ATM gene (11q22.3-23.1) that induce neurodegeneration Sasihuseyinoglu AS et al. Pediatr Allergy Immunol Pulmonol 31(1):9-14, 2018, Teive HAG et al. Parkinsonism Relat Disord 46:3-8, 2018. Clinically, A-T is characterized by ataxia, mucocutaneous telangiectasia, immunodeficiency, and malignancy. Movement disorders have been the most described and well-studied symptoms of A-T. Other studies have reported visuospatial processing disorders, executive function disorders and emotional regulation disorders, which are clinical manifestations that characterize cerebellar cognitive affective syndrome (CCAS) Choy KR et al. Dev Dyn 247(1):33-46, 2018. To describe the neurocognitive and emotional state of pediatric patients with ataxia-telangiectasia and to discuss whether they have cerebellar cognitive affective syndrome. This observational, cross-sectional, and descriptive study included 9 patients with A-T from May 2019 to May 2021. A complete medical history was retrieved, and tests were applied to assess executive functions, visual-motor integration and abilities, language, psychological disorders, and ataxia. Six girls and 3 boys agreed to participate. The age range was 6 to 14 years. The participants included five schoolchildren and four teenagers. Eight patients presented impaired executive functioning. All patients showed some type of error in copying and tracing (distortion) in the performance of visual perceptual abilities. Emotional disorders such as anxiety and depression were observed in six patients. Eight patients presented with dyslalia and impairments in word articulation, all patients presented with ataxia, and seven patients used a wheelchair. All patients presented symptoms consistent with CCAS and had variable cognitive performance.
Topics: Male; Female; Adolescent; Humans; Child; Ataxia Telangiectasia; Cross-Sectional Studies; Cerebellar Diseases; Cerebellar Ataxia; Cognition
PubMed: 36806980
DOI: 10.1007/s12311-023-01529-1 -
Consciousness and Cognition Mar 2023Strange face illusions describe a range of visual apparitions that occur when an observer gazes at their image reflected in a mirror or at another person's face in a... (Review)
Review
BACKGROUND
Strange face illusions describe a range of visual apparitions that occur when an observer gazes at their image reflected in a mirror or at another person's face in a dimly lit room. The illusory effects range from mild alterations in colour, or contrast, to the perception of distorted facial features, or new strange faces.The current review critically evaluates studies investigating strange face illusions, their methodological quality, and existing interpretations.
METHOD
Searches conducted using Scopus, PubMed, ScienceDirect and the grey literature until June 2022 identified 21 studies (N = 1,132; healthy participants n = 1,042; clinical participants n = 90) meeting the inclusion criteria (i.e., providing new empirical evidence relating to strange face illusions). The total sample had a mean age of 28.3 years (SD = 10.31) and two thirds (67 %) of participants tested to date are female. Results are reported using the Preferred Reporting Items for Systematic Reviews and meta-Analyses (PRISMA) guidelines. The review was preregistered at the Open Science Framework (OSF: https://osf.io/ek48d).
RESULTS
Pooling data across studies, illusory new strange faces are experienced by 58% (95%CI 48 to 68) of nonclinical participants. Study quality as assessed by the Appraisal Tool for Cross-Sectional Studies (AXIS) revealed that 3/21 (14.28%) studies were rated as high, 9/21 (42.86%) as moderate and 9/21 (42.86%) as low quality. Whilst the items relating specifically to reporting quality scored quite highly, those relating to study design and possible biases were lower and more variable. Overall, study quality accounted for 87% of the variance in reporting rates for strange faces, with higher quality being associated with lower illusion rates. The prevalence of illusions was also significantly greater in samples that were older, had higher proportions of female participants and for the interpersonal dyad (IGDT) compared to the mirror gaze paradigm (MGT). The moderating impact of study quality persisted in a multiple meta-regression involving participant age, paradigm type (IGDT vs MGT) and level of feature distortion. Our review point to the importance of reduced light levels, face stimuli and prolonged eye fixation for strange face illusions to emerge.
CONCLUSION
Strange face illusions reliably occur in both mirror-gazing and interpersonal gazing dyad paradigms. Further research of higher quality is required to establish the prevalence and particularly, the mechanisms underpinning strange face illusions.
Topics: Humans; Female; Adult; Male; Illusions; Cross-Sectional Studies; Face; Fixation, Ocular; Dissociative Disorders
PubMed: 36764163
DOI: 10.1016/j.concog.2023.103480 -
Journal of Vision Jan 2023Accurate memory regarding the location of an object with respect to one's own body, termed egocentric visuospatial memory, is essential for action directed toward the...
Accurate memory regarding the location of an object with respect to one's own body, termed egocentric visuospatial memory, is essential for action directed toward the object. Although researchers have suggested that the brain stores information related to egocentric visuospatial memory not only in the eye-centered reference frame but also in the other egocentric (i.e., head- or body-centered or both) reference frames, experimental evidence is scarce. Here, we tested this possibility by exploiting the perceptual distortion of head/body-centered coordinates via whole-body tilt relative to gravity. We hypothesized that if the head/body-centered reference frames are involved in storing the egocentric representation of a target in memory, then reproduction would be affected by this perceptual distortion. In two experiments, we asked participants to reproduce the remembered location of a visual target relative to their head/body. Using intervening whole-body roll rotations, we manipulated the initial (target presentation) and final (reproduction of the remembered location) body orientations in space and evaluated the effect on the reproduced location. Our results showed significant biases of the reproduced target location and perceived head/body longitudinal axis in the direction of the intervening body rotation. Importantly, the amount of error was correlated across participants. These results provide experimental evidence for the neural encoding and storage of information related to egocentric visuospatial memory in the head/body-centered reference frames.
Topics: Humans; Space Perception; Psychomotor Performance; Brain; Orientation; Mental Recall
PubMed: 36689216
DOI: 10.1167/jov.23.1.16