Ordinary Digital Camera Research Articles

BBMS: Investigation to Single Colour Image Visibility Improvement in Turbid Media through Biorthogonal Wavelet Based Depth-map Estimation

Electronic imaging needs good quality, high resolution (HR) digital images for highlighting finer details of the image. Normally images captured by ordinary digital camera are post pro cessed with available software instead of high cost CMOS sensor phased camera. Problem commonly faced with these images may get degraded due to the scattering media which deteriorates contrast, shifts colour, and make overall image whitish. Information from the distant objects suffer from poor medium transmission as well as noise amplification. Biorthogonal wavelet denoising (BWD), compress sparsely in frequency -time space, removes noise from depth estimation and makes the transmission smooth. Moreover, single image recovery is a serious challenge and ill posed problem. The recovered image improves compare to degraded image significantly and dis cards possibility of false edge detection as well as prevent colour shift and low contrast. Good quality images are found with objective evaluation. Moreover, different wavelets, thresholds, and decomposition levels have been studied and compared. Time complexity is linear due to wavelet domain analysis which makes the technique fast, reliable, and visually pleasing.

3D position and radioactivity estimation of radiation source by a simple directional radiation detector combined with structure from motion

It is important to visualize radioactive substances' position and distribution and estimate their radioactivity levels to reduce the exposure dose of workers in radioactive areas (such as decommissioning worksites of nuclear power stations) and improve nuclear security functions. To visualize the radioactive substance's three-dimensional (3D) location, a directional radiation detector with a cylindrical shield on a simple single-pixel gamma-ray detector was applied to the structure from motion (SfM) technology using an ordinary digital camera. Verification was performed by a system that combines SfM with a CdTe sensor probe having narrow directivity. 241Am radiation source's position was visualized by drawing the radiation source's image acquired by the gamma-ray detector on the work area 3D model reconstructed through SfM. Furthermore, as SfM is a simultaneous localization and mapping technology, the system measures the gamma rays while measuring the gamma-ray detector's dynamic position and posture information. The measurements can be acquired while the gamma-ray detector is freely moving in the work area. These methods visualized the radiation source's position and quantitatively estimated the radiation source's radioactivity.

Infant heart-rate measurement and oxygen desaturation detection with a digital video camera using imaging photoplethysmography.

To assess the feasibility of using an ordinary digital video camera to measure heart rate and detect oxygen desaturations in healthy infants. Heart rate and oxygen saturation were measured with a video camera by detecting small color changes in 28 infants' foreheads and compared with standard pulse oximetry measures. Multivariable regression examined the relationship between infant characteristics and heart-rate measurement precision. The average bias of camera heart-rate measures was -4.2 beats per minute (BPM) and 95% limits of agreement were ±43.8 BPM. Desaturations detected by camera were 75% sensitive (15/20) and had a positive predictive value of 20% (15/74). Lower birth-weight was independently correlated with more precise heart-rate measures (8.05 BPM per kg, [95% CI 0.764-15.3]). A digital video camera provides accurate but imprecise measures of infant heart rate and may provide a rough screening tool for oxygen desaturations.

Application of the Euler Motion Amplification Algorithm to Bridge Vibration Analysis

In this study,the Euler subtle motion amplification (MA) algorithm is applied to bridge vibration analysis. First,a series of digital images of bridge structures is continuously captured using an ordinary digital camera. Then,the micro-vibration of the bridge is amplified using the related algorithm of Euler MA. The time history image of the bridge specimen under conventional video sampling frequency is obtained by decomposing the amplified digital image. Lastly,the holographic dynamic displacement measurement results of the test bridge are obtained by analyzing the edge features of the marking points in the image sequences. The proposed analysis method is feasible compared with the displacement sensor and dial indicator. It can meet the application requirements of bridge dynamic displacement measurement. It can also perform preliminary quantitative analysis of several vibration characteristics of bridges and identify the micro-vibration displacements of a bridge structure.

Computational periscopy with an ordinary digital camera.

Computing the amounts of light arriving from different directions enables a diffusely reflecting surface to play the part of a mirror in a periscope-that is, perform non-line-of-sight imaging around an obstruction. Because computational periscopy has so far depended on light-travel distances being proportional to the times of flight, it has mostly been performed with expensive, specialized ultrafast optical systems1-12. Here we introduce a two-dimensional computational periscopy technique that requires only a single photograph captured with an ordinary digital camera. Our technique recovers the position of an opaque object and the scene behind (but not completely obscured by) the object, when both the object and scene are outside the line of sight of the camera, without requiring controlled or time-varying illumination. Such recovery is based on the visible penumbra of the opaque object having a linear dependence on the hidden scene that can be modelled through ray optics. Non-line-of-sight imaging using inexpensive, ubiquitous equipment may have considerable value in monitoring hazardous environments, navigation and detecting hidden adversaries.

Measurement of strain on concrete using an ordinary digital camera

Two-Dimensional Digital Image Correlation (2D-DIC) technique was applied in this experimental study, to measure the steel–concrete bond strain at concrete surface. The bond strain was caused by tensile force when it was subjected to embed reinforced bar of concrete block in the pullout test. A series of digital images from surface of concrete were taken by a semi-professional digital camera (Nikon D80) during the loading. Acquired images were used as input data for two DIC software to calculate deformation. After verifying the displacement results by measured LVDT results, full-field strain components on concrete were calculated at various levels of forces. The results show the measurement of displacement and strain by this method are acceptable to a great extent.

Documentation and analysis of traumatic injuries in clinical forensic medicine involving structured light three-dimensional surface scanning versus photography

Non-contact three-dimensional (3D) surface scanning has been applied in forensic medicine and has been shown to mitigate shortcoming of traditional documentation methods. The aim of this paper is to assess the efficiency of structured light 3D surface scanning in recording traumatic injuries of live cases in clinical forensic medicine. The work was conducted in Medico-Legal Centre in Benghazi, Libya. A structured light 3D surface scanner and ordinary digital camera with close-up lens were used to record the injuries and to have 3D and two-dimensional (2D) documents of the same traumas. Two different types of comparison were performed. Firstly, the 3D wound documents were compared to 2D documents based on subjective visual assessment. Additionally, 3D wound measurements were compared to conventional measurements and this was done to determine whether there was a statistical significant difference between them. For this, Friedman test was used. The study established that the 3D wound documents had extra features over the 2D documents. Moreover; the 3D scanning method was able to overcome the main deficiencies of the digital photography. No statistically significant difference was found between the 3D and conventional wound measurements. The Spearman's correlation established strong, positive correlation between the 3D and conventional measurement methods. Although, the 3D surface scanning of the injuries of the live subjects faced some difficulties, the 3D results were appreciated, the validity of 3D measurements based on the structured light 3D scanning was established. Further work will be achieved in forensic pathology to scan open injuries with depth information.

Visualization of Shear Cracks in a Reinforced Concrete Beam using the Digital Image Correlation

A low-cost digital image correlation system is used to visualize the formation and propagation of concrete cracking in a reinforced concrete beam. The system employed comprises an ordinary digital camera, a remote image recording controller (a smartphone) and a freely-available, open-source image correlation software package Ncorr. In this paper, the application of this system is demonstrated to obtain a comprehensive time-lapse of longitudinal strain fields developing before and after the onset of shear cracking, thus allowing one to fully appreciate the mechanisms of shear failure in the beam. It is shown that the longitudinal strain fields obtained from the DIC system are in a good agreement with hand-drawn crack maps and that obtained from nonlinear finite element analysis.

A REVIEW ON DIFFERENT UNDERWATER IMAGE ENHANCEMENT APPROACHES

In this review paper, different underwater image enhancement techniques are studied. Underwater imaging is a challenging in the zone of photography specifically for low resolution and also the ordinary digital camera. Because of there are some issues occur in underwater pictures like as low contrast, blurring, limited range visibility, noise, non-uniform lighting, color diminished, and bright artifacts so due to this reason the underwater picture is not clear. Hence in the underwater image enhancement, the main task is to improve the image visibility and restore the color by eliminating unwanted effect during the processing of imaging.

Weld Bead Geometry Dimensions Measurement based on Pixel Intensity by Image Analysis Techniques

Weld bead geometry dimensions were measured by Image Analysis Techniques (IAT’s) help to analyze an image based on the intensity level of its pixels. Based on intensity level the desired information is extracted from the image. Various techniques in image analysis help in improving the quality of the image thereby help to retrieve the information that is being sought. In present study, Autogenous Tungsten Inert Gas (TIG) bead-on-plate (BOP) welding was carried out on grade P-91 steel plates of size 100 mm × 50 mm × 6 mm. For welding, Taguchi’s L9 (33) orthogonal array design was adopted. The features like weld penetration, weld width and heat affected zone (HAZ) with their various subzones pixels intensity were measured by an IAT. The present IAT used the ordinary digital camera to capture the welded images. The dimensions of the weld features were compared to those measured by Leica-Q-win-V3 software. The study established that results in both methods were commensurate. Thus, the image analysis technique used in the study can be easily adopted for measurement of weld bead geometry as this method requires minimum human intervention and generates a complete picture of the weld profile.

Grey level replaces fluorescent intensity: Fluorescent paper sensor based on ZnO nanoparticles for quantitative detection of Cu2+ without photoluminescence spectrometer

This work uses ZnO nanoparticles as the probe and a case, proving that the grey level can replace fluorescent intensity to realize a quantitative detection function of paper-based Cu2+ sensor. Portable Cu2+ test papers were obtained through dipping filter papers in as-prepared ZnO sol possessing the Cu2+ quenching property. Based on grey level which is obtained through ordinary digital camera and computer, the detection function of the fabricated Cu2+ test paper is extended from qualitative detection relied on naked eyes to quantitative detection whose detection range is calculated to be 10–1000μM. The fabricated test papers also could resist the interruption of some competing ions and is a potential candidate for portable Cu2+ detection device with quantitative function. Since the strategy of replacing fluorescence intensity by grey level is based on the map relationship between the fluorescence intensity and the digital signal (grey level), it is promising to be applied to other fluorescent test papers to gain quantitative test papers aimed at corresponding chemicals. At the same time, the mechanism of Cu2+-induced fluorescence quenching was also investigated by fluorescence lifetime, UV–vis spectra, and photoluminescence spectra. And a static quenching mechanism based on the non-fluorescence complex formed by Cu2+ and Ox− is brought up.

Crack Mapping on Shear-critical Reinforced Concrete Beams using an Open Source Digital Image Correlation Software

Three reinforced concrete beams, one with no shear reinforcement and two others with shear reinforcement ratios of 0.4% and 1.1%, were tested to investigate the influence of stirrup spacing on the mode of failure, overall strength and ductility. The results show that the beam reinforced with closely-spaced shear reinforcement failed in a ductile manner, whereas the other two beams with large stirrup spacing and no stirrup exhibited only a small measure of ductility and failed in a brittle manner. The importance of the provisions of maximum spacing is highlighted to ensure adequate anchorage for the stirrups and prevent a premature shear failure to occur. The application of a non-contact monitoring system employing the open source digital image correlation software Ncorr, an ordinary digital camera and a smartphone is demonstrated to provide a visualization of the cracking process throughout the load history.

High-throughput phenotyping.

High-throughput phenotyping.

Adaptive high-dynamic-range imaging method and its application based on digital micromirror device

In the three-dimensional (3D) scanning measurement based on structured light techniques, the strong reflection surface is easy to produce local specular reflection due to the illumination of the structured light, which will cause the camera to be over-exposed, and therefore the geometry information of strong reflection surface cannot be detected. Since the digital micromirror device (DMD) has the modulating characteristics of the spatial information of incident light, an adaptive high-dynamic-range imaging method based on DMD is proposed to solve the problem of visual imaging of strong reflection surface. Firstly, a novel and computational imaging system is designed and built, and its optical model is also established. Then, the matching and mapping methods between DMD micromirrors and CMOS pixels are described in detail and realized. Meanwhile, we analyze the theory of the high-dynamic-range imaging based on per-pixel coded exposure, and design a coding control algorithm of light intensity to achieve the adaptive precision modulation of the intensity of incident light, so that the incident light in the imaging system is always in appropriate exposure intensity. The experiments show that the method can break through the limited dynamic range of the ordinary digital camera, and accurately control the intensity of incident light in each region of the measured strong reflection surfaces, and thus it can obtain the high-quality images of the local over-exposure area of the strong reflection surface. More importantly, the research will provide a new solution to the problem of 3D point cloud loss caused by local over-exposure of the strong reflection surface.

Extraction of Canine Cataract Object for Developing Handy Pre-diagnostic Tool with Fuzzy Stretching and ART2 Learning

Canine cataract is developed with aging and can cause the blindness or surgical treatment if not treated timely. The first observation must be made by pet owners but they do not have proper equipment and knowledge to see the abnormalities. In this paper, we propose an intelligent image processing method to extract canine cataract suspicious object from non-professional equipment such as ordinary digital camera and cellular phone photographs so that even casual owners of pet dog can make a pre-diagnosis of such a surgery-needed disease as soon as possible. The experiment shows that the proposed method is successful in most cases except the dog has similar colored hair to the color of cataract.

Template Matching Method for Recognition of Stone Inscripted Kannada Characters of Different Time Frames Based on Correlation Analysis

Stone inscripted literature speaks about the history, language of different regions of the world. Preservation of such document through digitalization process is become very important. To stop degradation and missing further, the analysis of the same will through light on historical events of that region. In this connection present work proposes a simple method of digitization using ordinary digital camera further, the pre-processing algorithm is implemented to enhance the image and improve the readability. Here it recognizes the Kannada characters based on template matching. In this method is normally implemented by first picking template and then it call the search image, then by simply comparing the template over each point in the search image and it calculate the sum of products between the coefficient. Based on this calculated product value it recognizes the character. Cross correlation technique is implemented in matching the characters coefficient. Experimental results shows, it demonstrates relatively high accuracy in recognizing Stone inscriptions characters of both Hoysala, Ganga time frames and with better time efficiency when compared to previous methods. DOI: http://dx.doi.org/10.11591/ijece.v4i5.6333

Liquid marbles for high-throughput biological screening of anchorage-dependent cells.

Stable liquid marbles (LM) are produced by coating liquid droplets with a hydrophobic powder. The used hydrophobic powder is produced by fluorosi-lanization of diatomaceous earth, used before to produce superhydrophobic structures. Here, the use of LM is proposed for high-throughput drug screening on anchorage-dependent cells. To provide the required cell adhesion sites inside the liquid environment of LM, surface-modified poly(l-lactic acid) microparticles are used. A simple method that takes advantage from LM appealing features is presented, such as the ability to inject liquid on LM without disrupting (self-healing ability), and to monitor color changes inside of LM. After promoting cell adhesion, a cytotoxic screening test is performed as a proof of concept. Fe(3+) is used as a model cytotoxic agent and is injected on LM. After incubation, AlamarBlue reagent is injected and used to assess the presence of viable cells, by monitoring color change from blue to red. Color intensity is measured by image processing and the analysis of pictures takes using an ordinary digital camera. The proposed method is fully validated in counterpoint to an MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carbo​xymethoxyphenyl)-2-(4-sulfophenyl)-2H-te​trazolium) colorimetric assay, a well-known method used for the cytotoxicity assessment.

Hiding a checkered-pattern carrier-screen image in a camouflaged halftone image

As carrier-screen images, we have developed checkered-pattern carrier-screen images, which can be physically decoded by superimposing a checkered pattern. We also proposed a decoding method by image sampling with an ordinary compact digital camera. To obtain a better decoding result, each carrier-screen image should be output at a low resolution. However, secret information can be detected when you observe the image carefully. Thus, a hiding process is an important technique. In this paper, we propose an advanced hiding method by embedding the carrier-screen image into another significant image to generate a camouflaged halftone image. The proposed embedding method can be performed through a simple sequential process of blending and halftoning.

Three-dimensional natural head position reproduction using a single facial photograph based on the POSIT method

We developed a new method to record and reproduce the three-dimensional natural head position (NHP) from a single photograph of a patient's face using a pose from orthography and scaling with iterations (POSIT) algorithm. We attached 4-mm spherical ceramic markers to the patient's face as feature points. A frontal photograph of the patient's NHP was taken using an ordinary digital camera parallel to the global horizon. Computed tomography (CT) was then performed on the patient with the markers. The ceramic marker positions were determined in the 2D image and corresponded to points in the 3D model. The 3D rotation matrix determined using the feature points via the POSIT method was applied to the CT model to reproduce the NHP. A skull phantom was used to evaluate the accuracy and reproducibility of the developed method. The degree difference (°) between the true and POSIT orientations in the roll, pitch, and yaw directions was quantified as the error. The mean accuracy was −0.04 ± 0.15°, −0.17 ± 0.50°, and −0.02 ± 0.37° in the roll, pitch, and yaw directions, respectively. The method developed was highly reproducible during intra-observer and inter-observer variation analyses. The accuracy of the method was clinically acceptable, and the procedure was time- and cost-effective. This method is accurate and inexpensive; additionally, it does not affect the patient's lip position, and we expect it to be routinely used during orthognathic surgery.

Application of Newton’s Zero Order Caustic for Analysis and Measurement: Part III – Light Scattering

When light is incident upon a liquid suspension that has an oblate spheroid shape, the size and presence of particles can be determined by measuring light intensity exiting the sample or by imaging the scattered light using a digital camera. This dual analysis system is facilitated by Newton’s zero order caustic formed within the sample, which creates a region of high intensity light inside the spheroid. Refraction of light exiting the spheroid directs a high percentage of scattered light near the zone of highest incident light intensity, which increases specific turbidity changes with particle size and facilitates analysis of gold nanoparticle plasmon resonance. Images taken with an ordinary digital camera at 90 degrees from the incident light can be analyzed using spatial autocorrelation in order to detect particle size. Original Research Article International Research Journal of Pure & Applied Chemistry, 4(2): 144-158, 2014 145