Built-in Camera Research Articles

ФОРМУВАННЯ ПІЗНАВАЛЬНОЇ САМОСТІЙНОСТІ УЧНІВ ЧЕРЕЗ РЕАЛІЗАЦІЮ МІЖПРЕДМЕТНИХ ЗВ’ЯЗКІВ ЗАСОБАМИ МОБІЛЬНИХ ТЕХНОЛОГІЙ

The article analyzes the directions of application of cross-curricular links in the modern conditions of secondary school. The experience of integration of cross-curricular links in teaching of natural subjects is characterized. The importance of the use of computer technologies in teaching natural sciences is emphasized, given their specificity. It is suggested as alternative information and communication technologies to use mobile devices during the educational process to realize cross-curricular links as a way of forming cognitive autonomy of students. In this work the directions of realization of cross-curricular relations for teaching of natural sciences are analyzed. The author proposes tasks that can be used to establish cross-curricular links in natural-science lessons, and provides electronic resources that can be used to create cross-curricular tasks, and outlines ways to accomplish these tasks through mobile technology. The text justifies the difficulties faced by teachers in the implementation of cross-curricular links in the teaching of natural subjects, in particular due to the inconsistency of some topics of school curricula, lack of a base of theoretical and methodological materials for the creation of cross-curricular problems for natural subjects, etc. The article shows the positive impact of cross-curricular integration on natural science lessons to increase cognitive interest and formation of cognitive autonomy of students. It is noted that the development of cross-curricular content tasks that are appropriate to use in the educational process of natural sciences remains an urgent task. A promising area of research is the integration of cross-curricular linkages in the course of completing project tasks and participating in project activities, which has a positive impact on students' cognitive abilities. Further exploration will be achieved through cross-curricular links in the research, taking into account the capabilities of mobile devices, both built-in (camera, digital sensors) and external (mobile applications) for the formation of students' cognitive autonomy. Key words: cognitive autonomy; cross-curricular links; tasks of cross-curricular content; subjects of the natural cycle; mobile technologies.

Automatic classification of common building materials from 3D terrestrial laser scan data

Automatic building material classification has been a popular research interest over the past decades because it is useful for construction management and facility management. Currently, the proposed methods for automatic material classification are mainly based on 2D images by using the visual features of building materials. A terrestrial laser scanner (TLS) with a built-in camera can generate a set of coloured laser scan data that contain the surface geometries of building materials. The laser scan data include not only the visual features of building materials but also other attributes such as material reflectance and surface roughness. With more attributes provided, laser scan data have the potential to improve the accuracy of building material classification. Therefore, this research aims to develop a TLS data-based classification method for common building materials using machine learning techniques. The developed technique uses material reflectance, HSV colour values, and surface roughness as the features for material classification. A database containing the laser scan data of ten common building materials was created and used for model training and validation with machine learning techniques. Different machine learning algorithms were compared, and the best algorithm showed an average classification accuracy of 96.7%, which demonstrated the feasibility of the developed method.

Efficient Eye Detection and Tracking using Smart Sensors

Smart sensing enables applications with lots of computer-based techniques and algorithms to work in a finer way. We are in era with intelligent machines around us and there sometimes provides a situation of spending of large amount of time due to lack of understanding of those devices. In this paper, we attempt on to find a new interaction method which ease the use of computers or increase interaction efficiency. The most interesting approach that enhances the best way of to find communication between machines and human beings. This enhances the way of communication with the digital devices. Our project enables to have communication using our eye in the desktop environment. This study focus on using eye gazing techniques that allows user to move the mouse cursor using his eye with interpretation of control commands. The desktop environment which has the inbuilt camera enables to achieve the goal in simple and efficient way. The study includes analysis of features using face detection and template matching which have presented promising results.

Budgeted video replacement policy in mobile crowdsensing

Mobile crowdsensing offers a new platform that recruits a suitable set of users to collectively complete an information collection/sensing task through users’ equipped devices. As a special case, video crowdsensing is to collect different video segments of the same event that are taken separately by the built-in cameras of mobile devices, and then combine them into a complete video. Mobile crowdsensing has attracted considerable attention recently due to the rich information that can be provided by videos. However, because of the limited caching space, a suitable video replacement policy is necessary. In this paper, we propose a Budgeted Video replaCement policy in mobile Video crowdsensing (BVCV), which first determines a video segment’s value according to its caching situation and natural attributes. Then, we formulate the video caching problem as a budgeted maximum coverage problem, which is a well-known NP-hard problem. Finally, we propose a practical greedy solution and also infer the approximate ratio, which could be regarded as the lower bound of BVCV to the optimal solution. Our experiments with the real mobility datasets (StudentLife dataset, Buffalo/phonelab-wifi dataset) show that, the proposed budgeted video replacement policy achieves a longer successfully delivered video length, compared with other general replacement policies.

Smartphone technology and its applications in urology: a review of the literature.

Smartphone technology has propelled the evolution of health-related mobile technology, referred to as mobile health (mHealth). With the rise of smartphone ownership and the growing popularity of health-related smartphone usage, mHealth offers potential benefits for both patients and health care providers. The objective of this review is to assess the current state of smartphone technology in urology. A literature search of PubMed database was conducted to identify articles reporting on smartphone technology in urology. Publications were included if they focused on smartphone mHealth technology pertinent to the field of urology or included an evaluation of urological applications in digital stores. We identified 50 publications focused on the use of smartphones in urology. Studies were then grouped into the following categories: smartphones employing the built-in camera and light source, applications specific to prostate cancer, urolithiasis, pediatric urology, and as educational tools for urologists. In 23/50 (46%) studies, smartphone technology/intervention was compared to a control group or to standard of care. In this regard, smartphone technology did not demonstrate benefit over standard of care in 13 studies. In contrast, in 10 studies, smartphone interventions were proven beneficial over current practice. Smartphone technology is constantly evolving and has the potential to improve urological care and education. Of concern to consumer and urologist alike is that these downloadable programs are limited due to the accuracy of their content, risk of confidentiality breach, and the lack of central regulation and professional involvement in their development.

Effect of Synthesized Bis-GMA and UDMA Nanofibers on Cuspal Flexure, Microhardness, Wear, Surface Roughness and Color Stability of Experimental Resin-Composites

Objective: To study the cuspal flexure (CF), Vickers microhardness (HV), three-body wear (W), surface roughness (SR) and color stability (CS) of experimental resin-composites reinforced with Bis-GMA and UDMA nanofibers synthesized by electrospinning technique.Materials and methods: Bis-GMA (Bis-GMA+TEGDMA+PEGDMA) and UDMA (UDMA+PEGDMA) nanofibers were synthesized by wet electrospinning technique and characterized by Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). After being ball-milled to a nanoscale size (< 100 nm) in a ball-milling machine (Retsch – PM 400, Haan, Germany), these nanofibers were added to a prepared experimental resin-composite. This study was divided, according to the percent and type of added nanofibers, into eight groups (n=10/group except for color stability n=11): one control group, three groups reinforced with 7, 11 and 15 wt% Bis-GMA nanofibers and four groups reinforced with 7, 11, 15 and 20 wt% UDMA nanofibers. For each of these groups, CF, HV, W, SR and CS were studied. CF was studied by the digital image correlation method which analyzes the displacement of an object using a USB digital microscope with a built-in camera (COMET xS, Steinbichler Optotechnik GmbH, Neubeuern, Germany). HV was measured according to the ASTM E-384:1999 using a Digital Display Vickers Microhardness Tester (ZHVµ Micro Vickers Hardness Tester, Indentec Hardness Testing, Zwick Roell Co., Ltd. Atlanta, USA). W testing was carried out according to ISO/TS 14569:2001 using a custom-made cusp-on-disc sliding machine. Measurement of SR was performed according to ISO 25178-2:2012 and CS testing was carried out according to the regulations of ISO 4049; 2009 using a portable reflective spectrophotometer (X-Rite, model RM200QC, Neu-Isenburg, Germany). Data were collected and submitted to One-way ANOVA and post-hoc Tukey and Dunnett’s T3 tests with the significance level set at (p ≤ 0.05). Results: Pure forms of Bis-GMA (70-100 nm) and UDMA (50-100 nm) nanofibers were confirmed by SEM and FTIR. One-way ANOVA revealed significant differences between studied groups for CF, HV, W and SR (p = 0.001) but not for CS (p = 0.068). For both types of nanofibers, compared to the control group, reinforced groups showed lower CF, HV and SR and greater W results. For CS, there was no consistent trend of results of experimental groups that were comparable to that of control group. Within the range of added nanofibers (7-20 wt%), Bis-GMA nanofibers exhibited more favourable HV and W results than UDMA nanofibers, while the reverse was the case for CF and SR. Both nanofibers exhibited comparable CS results.Clinical Significance: A resin-composite reinforced with such nanofibers showing improved CF and unfavorably lower HV and more W should be used as a base layer and covered with a layer of another resin-composite with enhanced surface properties.

Orotracheal intubation guided with a vivasight single lumen tube in unanticipated difficult airway

Introduction The management of an unanticipated difficult airway is a challenge for any anesthesiologist. Over the years, devices have been developed to improve intubation in cases of difficulty. Methods We present the case of a patient with an unanticipated difficult airway, who was intubated during the first attempt thanks to the use of a VivaSight tube. The consent for the publication of this case was obtained by the patient. He is a 57-year-old man, who underwent a programmed left upper lobectomy. Predictors of airway assessment performed in preanesthesia classified the patient as low risk. The initial plan included the use of a VivaSight SL tube and a bronchial blocker for left lung collapse under direct vision during surgery. Results The patient underwent general anesthesia. After 2 minutes of induction and verify that the ventilation could be carried out without problem, a direct laryngoscopy was performed. A spheroidal tumor adhered to the epiglottis was visualized (figure 1), turning the patient into a Cormack-Lehane III grade. Because we had prepared a VivaSight single lumen endotracheal tube for intubation, we chose to perform intubation guided by the video of the camera integrated in the VivaSight tube. The intubation sequence can be seen in the images of figure 1. The result was an intubation of less than a minute in duration and without incidents during the first attempt. Discussion VivaSight is a special tracheal tube, which has a built-in direct vision camera. It is used mostly in anesthesia for thoracic surgery. There are 2 models: double lumen and single lumen. The single lumen can usually be used together with bronchial blockers without requiring a fiber optic bronchoscope. The main advantages described with the use of these devices are the visualization of the correct position of the tube and the visualization of the correct position of the bronchial blocker2. Other authors have shown that the use of the VivaSight tube decreases intubation time and number of attempts with respect to video laryngoscopy in emergencies3. In the case that we have described, the camera of the tube allowed us to perform an intubation in a case of unanticipated difficult airway. Therefore, we think that the VivaSight tube should be an option to consider in the cases of patients with anticipated or known difficult airway in thoracic surgery. However, it is necessary to develop prospective studies that provide more evidence.

Low-cost UAV as a Source of Image Data for Detection of Land Cover Changes

Data from remote sensing methods have been used successfully to monitor changes in the landscape. At present, unmanned aerial vehicles (UAVs) are also increasingly used. The article shows how to use the middle-class dron, specifically DJI Phantom 3 with a built-in camera, to monitor and document changes in the vicinity of small water bodies where a part of the shore is poorly accessible or totally unavailable. The obtained data can be further processed by conventional digital image processing methods such as image classification, highlighting through spectral indexes, or even visually comparing.

Navigation Systems for the Blind and Visually Impaired: Past Work, Challenges, and Open Problems.

Over the last decades, the development of navigation devices capable of guiding the blind through indoor and/or outdoor scenarios has remained a challenge. In this context, this paper’s objective is to provide an updated, holistic view of this research, in order to enable developers to exploit the different aspects of its multidisciplinary nature. To that end, previous solutions will be briefly described and analyzed from a historical perspective, from the first “Electronic Travel Aids” and early research on sensory substitution or indoor/outdoor positioning, to recent systems based on artificial vision. Thereafter, user-centered design fundamentals are addressed, including the main points of criticism of previous approaches. Finally, several technological achievements are highlighted as they could underpin future feasible designs. In line with this, smartphones and wearables with built-in cameras will then be indicated as potentially feasible options with which to support state-of-art computer vision solutions, thus allowing for both the positioning and monitoring of the user’s surrounding area. These functionalities could then be further boosted by means of remote resources, leading to cloud computing schemas or even remote sensing via urban infrastructure.

Non-Contact Monitoring of Breathing Pattern and Respiratory Rate via RGB Signal Measurement.

Among all the vital signs, respiratory rate remains the least measured in several scenarios, mainly due to the intrusiveness of the sensors usually adopted. For this reason, all contactless monitoring systems are gaining increasing attention in this field. In this paper, we present a measuring system for contactless measurement of the respiratory pattern and the extraction of breath-by-breath respiratory rate. The system consists of a laptop’s built-in RGB camera and an algorithm for post-processing of acquired video data. From the recording of the chest movements of a subject, the analysis of the pixel intensity changes yields a waveform indicating respiratory pattern. The proposed system has been tested on 12 volunteers, both males and females seated in front of the webcam, wearing both slim-fit and loose-fit t-shirts. The pressure-drop signal recorded at the level of nostrils with a head-mounted wearable device was used as reference respiratory pattern. The two methods have been compared in terms of mean of absolute error, standard error, and percentage error. Additionally, a Bland–Altman plot was used to investigate the bias between methods. Results show the ability of the system to record accurate values of respiratory rate, with both slim-fit and loose-fit clothing. The measuring system shows better performance on females. Bland–Altman analysis showed a bias of −0.01 breathsmin, with respiratory rate values between 10 and 43 breathsmin. Promising performance has been found in the preliminary tests simulating tachypnea.

Smartphone-based respiratory rate estimation using photoplethysmographic imaging and discrete wavelet transform

Respiratory rate is a key vital sign that needs daily monitoring for hospital patients in general and those with respiratory conditions in particular. Moreover, it is a predictor of major heart conditions. Yet, studies have shown that it is widely neglected in hospital care due partially to the discomfort caused by the required equipment. In this paper, we propose a smartphone-based method for accurate measurement of the respiratory rate using the video of the skin surface as recorded by the smartphone built-in camera in the presence of the flash light. From this input, we use frame averaging to extract a photoplethysmographic signal of the red, green, and blue channels. Next, we apply discrete wavelet transform on the best representative photoplethysmographic signal for respiratory signal extraction and estimate the rate. Fifteen subjects participated in the testing and evaluation. The maximum absolute error was 0.67 breaths/min, whereas the root mean square error was 0.366 breaths/min. The average percentage error and average percentage accuracy using our approach were 2.2%, 97.8% respectively. A comparison with other works in the literature reveal a superior performance in terms of accuracy, ease of use, and cost.

User Recruitment System for Efficient Photo Collection in Mobile Crowdsensing

Mobile crowdsensing recruits a group of mobile users to cooperatively perform a common sensing job with their smart devices. As a special issue, photo crowdsensing allows users to utilize the built-in cameras of mobile devices to take photos for an event or a target. Then, the photos can be used in numerous application areas, such as target reconstruction, scenario reduction, and so on. Therefore, photo crowdsensing has attracted considerable attention recently due to the rich information that can be provided by images. In this paper, we focus on using the photos to make reconstructions for specific targets. Furthermore, we develop a user recruitment system for efficient photo collecting in mobile crowdsensing (RSMC), where the task requesters publish a sensing task to the users, and the map is gridded according to the locations of the sensing targets. Then, we use a semi-Markov model to calculate the user's utility for the sensing task. Finally, a user recruitment strategy is devised to recruit the optimal $k$ users for finishing the sensing task. We conduct extensive simulations based on three widely used real-world traces: roma/taxi , epfl , and geolife . The results show that, compared with other recruitment strategies, RSMC takes the largest number of efficient photos for the sensing task.

Real-time Indocyanine Green Videolymphography Navigation for Lymphaticovenular Anastomosis

Summary:Indocyanine green (ICG) lymphography is a useful imaging modality for evaluation of lymphedema and detection of lymphatic vessels. It also allows us to ensure patency of the anastomosed vessels intraoperatively. However, strong light from the operating microscope usually disturbs ICG fluorescence imaging. Only some built-in ICG camera systems with specific operating microscopes make real-time ICG lymphography possible in lymphaticovenular anastomosis (LVA). We applied a new high-resolution ICG videolymphography system, which is separated from the operating microscope. Because the system can divide near-infrared fluorescence light of ICG from visible light of the operating microscope, real-time ICG videolymphography-navigated LVA under operating microscope illumination is possible regardless types of operating microscopes. The study involved 10 patients with upper extremity lymphedema characterized by International Society of Lymphology stage 2 and treated by 3 lymphaticovenular anastomoses at the forearm (30 lymphaticovenular anastomoses incorporating 30 lymphatic vessels) under real-time ICG videolymphography. The rate of intraoperative detection of lymphatic vessels using real-time ICG videolymphography was 86.7% (0.25–0.85 mm in diameter), and that of lymph flow through the lymphaticovenular anastomoses was 76.7%. None of lymphatic vessels and no flow were detected under the microscope light by means of another non-built-in ICG lymphography camera. Real-time ICG videolymphography in LVA is beneficial, because the surgeon could find lymphatic vessels easily by checking dual images of original view and ICG fluorescent view and ensure accuracy of the LVA in a suture by a suture without any pauses of the surgical procedures.

An octuplex lateral flow immunoassay for rapid detection of antibiotic residues, aflatoxin M1 and melamine in milk

Antibiotic residues, aflatoxin M1 and melamine are three major types of chemical contaminants in milk. However, analytical approach for the simultaneous detection of these chemicals is currently not available. In this study, an octuplex lateral flow immunoassay was developed to address this problem. Specific monoclonal antibodies and receptor were prepared and were bound onto gold nanoparticles to form eight antibody/receptor-gold nanoparticle conjugates as detection probes. Eight corresponding hapten-protein conjugates were synthesized and immobilized on distinct test zones of nitrocellulose membrane as capture antigens. Thus octuplex immune-reactions can then simultaneously occur on a single strip. For qualitative analysis, the result can be visually judged by naked eyes and the cut-off values of quinolones, tetracyclines, β-lactams, sulfonamides, chloramphenicol, streptomycin, aflatoxin M1 and melamine were measured to be 12–80 ng/mL, 16–32 ng/mL, 2–80 ng/mL, 4–80 ng/mL, 1.2 ng/mL, 50 ng/mL, 0.5 ng/mL and 200 ng/mL, respectively. For semi-quantitative analysis, the test lines can be photographed by a built-in camera of smartphone and the line intensities can be analyzed by Image J software. The limits of detection for all the chemicals were far below the regulatory limits set by authorities. Furthermore, the detection time of this method was less than 20 min. Consequently, the developed immunoassay in this study is a promising approach for rapidly screening common chemical contaminants in milk.

Flux Puppy – An open-source software application and portable system design for low-cost manual measurements of CO2 and H2O fluxes

Manual chamber-based measurements of CO2 (and H2O) fluxes are important for understanding ecosystem carbon metabolism. Small opaque chambers can be used to measure leaf, stem and soil respiration. Larger transparent chambers can be used to measure net ecosystem exchange of CO2, and small jars often serve this purpose for laboratory incubations of soil and plant material. We developed an Android application (app), called Flux Puppy, to facilitate chamber-based flux measurements in the field and laboratory. The app is designed to run on an inexpensive handheld Android device, such as a tablet or phone, and it has a graphical user interface that communicates with a LI-COR LI-820 and LI-830 (CO2) or LI-840 and LI-850 (CO2/H2O) infrared gas analyzer. The app logs concentrations of CO2 and H2O, cell temperature and pressure at 1 Hz, displays the output graphically, and calculates the linear regression slope, R-squared, and standard error of the CO2 time series. A metadata screen allows users to enter operator, site, and plot information, as well as take a photograph using the Android device’s built-in camera, and log measurement location using the device GPS. Additionally, there is a notes field, which can be revised after the measurements are taken. Data files (the 1 s raw data, photograph, and metadata including statistics calculated from the raw data) are then transmitted off the device through file sharing options (Gmail, Outlook, Google Drive, Dropbox etc.). Because Flux Puppy code is open-source (available on GitHub) and the flux measurement system we describe is relatively inexpensive and straightforward to assemble, it should be of broad interest to the carbon cycling community.

Mobile Phone-Based Use of the Photoplethysmography Technique to Detect Atrial Fibrillation in Primary Care: Diagnostic Accuracy Study of the FibriCheck App.

BackgroundMobile phone apps using photoplethysmography (PPG) technology through their built-in camera are becoming an attractive alternative for atrial fibrillation (AF) screening because of their low cost, convenience, and broad accessibility. However, some important questions concerning their diagnostic accuracy remain to be answered.ObjectiveThis study tested the diagnostic accuracy of the FibriCheck AF algorithm for the detection of AF on the basis of mobile phone PPG and single-lead electrocardiography (ECG) signals.MethodsA convenience sample of patients aged 65 years and above, with or without a known history of AF, was recruited from 17 primary care facilities. Patients with an active pacemaker rhythm were excluded. A PPG signal was obtained with the rear camera of an iPhone 5S. Simultaneously, a single‑lead ECG was registered using a dermal patch with a wireless connection to the same mobile phone. PPG and single-lead ECG signals were analyzed using the FibriCheck AF algorithm. At the same time, a 12‑lead ECG was obtained and interpreted offline by independent cardiologists to determine the presence of AF.ResultsA total of 45.7% (102/223) subjects were having AF. PPG signal quality was sufficient for analysis in 93% and single‑lead ECG quality was sufficient in 94% of the participants. After removing insufficient quality measurements, the sensitivity and specificity were 96% (95% CI 89%-99%) and 97% (95% CI 91%-99%) for the PPG signal versus 95% (95% CI 88%-98%) and 97% (95% CI 91%-99%) for the single‑lead ECG, respectively. False-positive results were mainly because of premature ectopic beats. PPG and single‑lead ECG techniques yielded adequate signal quality in 196 subjects and a similar diagnosis in 98.0% (192/196) subjects.ConclusionsThe FibriCheck AF algorithm can accurately detect AF on the basis of mobile phone PPG and single-lead ECG signals in a primary care convenience sample.

An Innovative application for code generation of mathematical equations and problem solving

Mathematics is the cradle of all creations, without which the world cannot move an inch. Mathematical functions are ‘extensively’ used in physics, ‘structurally’ used in graphics, ‘practically’ used in civil engineering, ‘potentially’ used in mechanical engineering and in many other fields as well. One fairly common difficulty faced by the engineers and scientists is to find the right function that solves their problem. This involves a lot of time consuming tasks. The idea proposed here is an android application that captures the mathematical expression using a built-in camera which produces a java code that can be utilized for solving the inputs of their needs. Along with the code, it also displays a basic plot of the function, which will be more helpful for selecting the apt solution for any problem. There are many applications in the market which can compute the result of a mathematical equation. But, this application will give an executable java code which can be used for further problem solving. So, the application is unique in its way and this is a new dimension of using image processing for code generation. This application supports polynomial, logarithmic, trigonometric and exponential functions up to four variables.

THREE-DIMENSIONAL RECORDING AND PHOTOREALISTIC MODEL RECONSTRUCTION FOR VIRTUAL MUSEUM APPLICATION – AN EXPERIENCE IN MALAYSIA

Abstract. In recent years, museums are utilizing the ability of virtual reality (VR) technologies to visualize their collections in three-dimensional (3D) environment. The demands for 3D digitization of cultural heritage have increase greatly to facilitate the development of virtual museum. Among the available techniques, the use of laser scanning for digital recording and 3D reproduction of the heritage sites and archaeological artefacts are technically more reliable due to its rapid and high resolution data capture. However, the suitable 3D laser scanners used greatly depend on the level of details and size of an object. This research used medium and close-range type of laser scanners to digitally record the heritage objects. The aim of this research was to develop methodology framework for digital recording and 3D reproduction of archaeological artefact and heritage sites in Malaysia by using terrestrial laser scanning technology. Besides, this research focused on the reconstruction of photorealistic 3D models based on the colour information yield by close-range photogrammetry. The colour descriptions were obtained either by built-in camera or externally integrated camera on the laser scanner. For better colour descriptions, external images were captured by independent Nikon D300s digital camera. The geometric model accuracy of A’Famosa and terracotta Buddha statuette was in 5 mm and 0.41 mm respectively. 3D flythrough animation was rendered by using the coloured point clouds model. The development of 3D Virtual Walkthrough Museum (3DVWM) utilized the 3D PDF document and SCENE WebShare platform to offer realistic visualization experience to the visitors where the reality-based models could be manipulate in 3D geometric aspects and use of metric analysis. Thus, 3DVWM can facilitate the virtual museum application in Malaysia and enable wider visitors to virtually appreciate the cultural heritage in Malaysia. Thus, this indirectly stimulates the tourism industry in our country.

Tackling In-Camera Downsizing for Reliable Camera ID Verification

The photo-response non-uniformity (PRNU) of an imaging sensor can be regarded as a biometric identifier unique to each camera. This modality is referred to as camera ID. The underlying process for estimating and matching camera IDs is now well established, and its robustness has been studied under a variety of processing. However, the effect of in-camera downsizing on camera ID verification has not yet been methodologically addressed. In this work, we investigate limitations imposed by built-in camera downsizing methods and tackle the question of how to obtain a camera ID so that attribution is possible with lower resolution media. For this purpose, we developed an application that gathers photos and videos at all supported resolutions by controlling camera settings. Analysis of media obtained from 21 smartphone and tablet cameras shows that downsizing of photos by a factor of 4 or higher suppresses PRNU pattern significantly. On the contrary, it is observed that source of unstabilized videos can be verified quite reliably at almost all resolutions. We combined our observations in a camera ID verification procedure considering downsized media.

Use of mobile camera as a standby for documentation of papanicolaou smear and cervicography: Three case reports

Cervical cancer is more common in countries and regions with poor facilities, and they are often not well equipped with high-end equipment required for diagnosis. By way of this article, we would like to demonstrate with three case reports the use of minimal and available technology for documentation in screening and prevention of cervical cancer in clinics having basic facilities. The mobile camera is commonly available with clinicians/technicians these days. It can be used for capturing pictures of the cervix if colposcope is not available or for clicking microscopic pictures of Papanicolaou smears or histology slides to document abnormalities when inbuilt cameras are not functional or not available.