Fast Control of JPEG Compression Rate

2019 ◽  
pp. 163-180
Author(s):  
Ilia V. Safonov ◽  
Ilya V. Kurilin ◽  
Michael N. Rychagov ◽  
Ekaterina V. Tolstaya
Keyword(s):  
Jpeg Compression ◽  
Compression Rate ◽  
Fast Control

scholarly journals Usage analysis of SVD, DWT and JPEG compression methods for image compression

2021 ◽  
Vol 14 (2) ◽  
pp. 99
Author(s):  
Dewa Ayu Indah Cahya Dewi ◽  
I Made Oka Widyantara
Keyword(s):  
Image Compression ◽  
Compression Ratio ◽  
Jpeg Compression ◽  
Telecommunication Networks ◽  
Compression Rate ◽  
Image Size ◽  
Image File ◽  
File Storage ◽  
Usage Analysis ◽  
Processing Techniques

Through image compression, can save bandwidth usage on telecommunication networks, accelerate image file sending time and can save memory in image file storage. Technique to reduce image size through compression techniques is needed. Image compression is one of the image processing techniques performed on digital images with the aim of reducing the redundancy of the data contained in the image so that it can be stored or transmitted efficiently. This research analyzed the results of image compression and measure the error level of the image compression results. The analysis to be carried out is in the form of an analysis of JPEG compression techniques with various types of images. The method of measuring the compression results uses the MSE and PSNR methods. Meanwhile, to determine the percentage level of compression using the compression ratio calculation. The average ratio for JPEG compression was 0.08605, the compression rate was 91.39%. The average compression ratio for the DWT method was 0.133090833, the compression rate was 86.69%. The average compression ratio of the SVD method was 0.101938833 and the compression rate was 89.80%.

Secure Watermarking using Diophantine Equations for Authentication and Recovery

2015 ◽  
Vol 3 (2) ◽  
Author(s):  
Jayashree Nair ◽  
T. Padma
Keyword(s):  
Diophantine Equation ◽  
Diophantine Equations ◽  
Jpeg Compression ◽  
Authentication Scheme ◽  
Original Image ◽  
Invariant Features ◽  
Jpeg2000 Compression ◽  
Frequency Properties ◽  
Visual Authentication

This paper describes an authentication scheme that uses Diophantine equations based generation of the secret locations to embed the authentication and recovery watermark in the DWT sub-bands. The security lies in the difficulty of finding a solution to the Diophantine equation. The scheme uses the content invariant features of the image as a self-authenticating watermark and a quantized down sampled approximation of the original image as a recovery watermark for visual authentication, both embedded securely using secret locations generated from solution of the Diophantine equations formed from the PQ sequences. The scheme is mildly robust to Jpeg compression and highly robust to Jpeg2000 compression. The scheme also ensures highly imperceptible watermarked images as the spatio –frequency properties of DWT are utilized to embed the dual watermarks.

Out-of-plane static compression and energy absorption of paper hierarchical corrugation sandwich panels

2021 ◽  
pp. 030932472110085
Author(s):  
Huineng Wang ◽  
Yanfeng Guo ◽  
Yungang Fu ◽  
Dan Li
Keyword(s):  
Yield Strength ◽  
Bearing Capacity ◽  
Energy Absorption ◽  
Sandwich Panel ◽  
Second Order ◽  
Compression Rate ◽  
Static Compression ◽  
First Order ◽  
Out Of Plane ◽  
Analytical Approaches

This study introduces the opinion of the corrugation hierarchy to develop the second-order corrugation paperboard, and explore the deformation characteristics, yield strength, and energy absorbing capacity under out-of-plane static evenly compression loading by experimental and analytical approaches. On the basis of the inclined-straight strut elements of corrugation unit and plastic hinge lines, the yield and crushing strengths of corrugation unit were analyzed. This study shows that as the compressive stress increases, the second-order corrugation core layer is firstly crushed, and the first-order corrugation structures gradually compacted until the failure of entire structure. The corrugation type has an obvious influence on the yield strength of the corrugation sandwich panel, and the yield strength of B-flute corrugation sandwich panel is wholly higher than that of the C-flute structure. At the same compression rate, the flute type has a significant impact on energy absorption, and the C-flute second-order corrugation sandwich panel has better bearing capacity than the B-flute structure. The second-order corrugation sandwich panel has a better bearing capacity than the first-order structure. The static compression rate has little effect on the yield strength and deformation mode. However, with the increase of the static compression rate, the corrugation sandwich panel has a better cushioning energy absorption and material utilization rate.

The Iterative Development and Testing of an Interactive Mobile Application for Skill Retention of Cardiopulmonary Resuscitation Among High School Students: A Pilot Study

2021 ◽  
pp. 104687812110326
Author(s):  
Adeel Arif ◽  
Amber Arif ◽  
Kimberly Anne Fasciglione ◽  
Farrukh Nadeem Jafri
Keyword(s):  
High School ◽  
High School Students ◽  
Cardiopulmonary Resuscitation ◽  
Mobile Apps ◽  
Low Cost ◽  
Survival Rates ◽  
Compression Rate ◽  
School Students ◽  
Skill Retention ◽  
Before And After

Abstract: Background Locations concentrated with High School (HS) students tend to have lower out-of-hospital cardiac arrest (OHCA) survival rates. Mobile applications (apps) have the capability to augment cardiopulmonary resuscitation (CPR) skill retention as a low-cost, accessible training method. Methods An iterative process to develop an app to reinforce CPR skills emphasizing hand placement, compression rate, real-time feedback, and recurring tips is described. The app was tested on HS students to measure its impact on quality and comfort of CPR using Likert surveys and skills assessments before and after one month of usage. CPR Score and compression rate were measured using the Laerdal™ Little Anne Manikin QCPR software. Results Fourteen HS students participated in a prospective observational study. It was found that the use of the developed app was associated with improved CPR performance (80.43% v. 87.86%, p=0.01-0.02, 95% CI=2.20-12.66) after one month. Additionally, improvements were demonstrated in compression rate accuracy (21.43% v. 64.29%, p=0.041, 95% CI=0.132-0.725), increased comfort performing CPR (3.86 v. 4.79, p<0.001, 95% CI =0.99-1.00) and comfort performing CPR on strangers (2.71 v. 4.42, p<0.001, 95% CI=1.24-2.19). In addition, for every time the app was used, CPR performance increased by 0.5668% (p=0.0182). Conclusion Findings suggest that mobile apps may have promising implications as augmentative tools for CPR curriculums.

scholarly journals Image Statistics Preserving Encrypt-then-Compress Scheme Dedicated for JPEG Compression Standard

Entropy ◽  
2021 ◽  
Vol 23 (4) ◽  
pp. 421
Author(s):  
Dariusz Puchala ◽  
Kamil Stokfiszewski ◽  
Mykhaylo Yatsymirskyy
Keyword(s):  
Statistical Analysis ◽  
Image Encryption ◽  
Experimental Studies ◽  
Quality Measures ◽  
Input Image ◽  
Jpeg Compression ◽  
Image Statistics ◽  
Compression Stage ◽  
Wide Range ◽  
The Impact

In this paper, the authors analyze in more details an image encryption scheme, proposed by the authors in their earlier work, which preserves input image statistics and can be used in connection with the JPEG compression standard. The image encryption process takes advantage of fast linear transforms parametrized with private keys and is carried out prior to the compression stage in a way that does not alter those statistical characteristics of the input image that are crucial from the point of view of the subsequent compression. This feature makes the encryption process transparent to the compression stage and enables the JPEG algorithm to maintain its full compression capabilities even though it operates on the encrypted image data. The main advantage of the considered approach is the fact that the JPEG algorithm can be used without any modifications as a part of the encrypt-then-compress image processing framework. The paper includes a detailed mathematical model of the examined scheme allowing for theoretical analysis of the impact of the image encryption step on the effectiveness of the compression process. The combinatorial and statistical analysis of the encryption process is also included and it allows to evaluate its cryptographic strength. In addition, the paper considers several practical use-case scenarios with different characteristics of the compression and encryption stages. The final part of the paper contains the additional results of the experimental studies regarding general effectiveness of the presented scheme. The results show that for a wide range of compression ratios the considered scheme performs comparably to the JPEG algorithm alone, that is, without the encryption stage, in terms of the quality measures of reconstructed images. Moreover, the results of statistical analysis as well as those obtained with generally approved quality measures of image cryptographic systems, prove high strength and efficiency of the scheme’s encryption stage.

scholarly journals Pressure Equilibrium Time of a Cyclic-Olefin Copolymer

Polymers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 2309
Author(s):  
Benedikt Roth ◽  
Dietmar Drummer
Keyword(s):  
Dynamic Compression ◽  
Flow Behavior ◽  
Superposition Principle ◽  
Applied Pressure ◽  
Thermal Shrinkage ◽  
Compression Rate ◽  
Rate Dependency ◽  
Equilibrium Time ◽  
Simulation Techniques ◽  
Pressure Equilibrium

Integrative simulation techniques for predicting component properties, based on the conditions during processing, are becoming increasingly important. The calculation of orientations in injection molding, which, in addition to mechanical and optical properties, also affect the thermal shrinkage behavior, are modeled on the basis of measurements that cannot take into account the pressure driven flow processes, which cause the orientations during the holding pressure phase. Previous investigations with a high-pressure capillary rheometer (HPC) and closed counter pressure chamber (CPC) showed the significant effect of a dynamically applied pressure on the flow behavior, depending on the temperature and the underlying compression rate. At a constant compression rate, an effective pressure difference between the measuring chamber and the CPC was observed, which resulted in a stop of flow through the capillary referred to as dynamic compression induced solidification. In order to extend the material understanding to the moment after dynamic solidification, an equilibrium time, which is needed until the pressure signals equalize, was evaluated and investigated in terms of a pressure, temperature and a possible compression rate dependency in this study. The findings show an exponential increase of the determined equilibrium time as a function of the holding pressure level and a decrease of the equilibrium time with increasing temperature. In case of supercritical compression in the area of a dynamic solidification, a compression rate dependency of the determined equilibrium times is also found. The measurement results show a temperature-invariant behavior, which allows the derivation of a master curve, according to the superposition principle, to calculate the pressure equilibrium time as a function of the holding pressure and the temperature.

scholarly journals EVIDENCE THAT TWO LOCI PREDOMINANTLY DETERMINE THE DIFFERENCE IN SUSCEPTIBILITY TO THE HIGH PRESSURE NEUROLOGIC SYNDROME TYPE I SEIZURE IN MICE

Genetics ◽  
1981 ◽  
Vol 99 (2) ◽  
pp. 285-307
Author(s):  
R D McCall ◽  
D Frierson
Keyword(s):  
High Pressure ◽  
Inbred Mouse ◽  
Inbred Strains ◽  
Chromosome 17 ◽  
Seizure Threshold ◽  
Mouse Strains ◽  
Compression Rate ◽  
Type I ◽  
Major Locus ◽  
The Difference

ABSTRACT Most mammals tested, when exposed to increasing pressure in helium/oxygen atmospheres, exhibit progressive motor disturbances culminating in two, usually successive, well-differentiated convulsive seizures. The seizures are highly reproducible components of the constellation of events that collectively constitute the High Pressure Neurologic Syndrome (HPNS). In the present study, we present evidence that the mean difference in seizure threshold pressures of the first seizure to occur (HPNS Type I) between inbred mouse strains DBA/2J and C57BL/6J is predominantly determined (&gt; 60%) by the expression of a major locus—possibly linked to the H-2 locus on chromosome 17—and a minor locus, probably unlinked. This outcome is derived from applications of the maximum likelihood modeling procedure of Elston and Stewart (1973) and Stewart and Elston (1973) to eleven models of genetic determinacy and tests (including breeding tests) of "preferred" models so derived using BXD recombinant inbred strains that show the following: The major locus exhibits conditional dominance characteristics depending upon compression rate and minor locus genotype. At a constant mean compression rate of 100 atm hr-1, the major locus manifests strong, though incomplete, dominance apparently independent of minor locus genotype. Its expression is, however, highly sensitive to compression rate, losing its dominance altogether at a linear rate of 1,000 atm hr-1. The major locus interacts with the weakly dominant and relatively compression-rate-insensitive minor locus to retain dominance at fast compression only when the dominant alleles of both loci are present. A principal finding of this study is that employing two compression rates permits fuller genetic characterization of murine high-pressure seizure susceptibility differences than could be achieved by use of a single compression rate.

scholarly journals Radiological and clinical outcomes of balloon kyphoplasty for osteoporotic vertebral compression fracture in patients with rheumatoid arthritis

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Ji Guo ◽  
Weifeng Zhai ◽  
Licheng Wei ◽  
Jianpo Zhang ◽  
Lang Jin ◽  
...  
Keyword(s):  
Rheumatoid Arthritis ◽  
Vertebral Fractures ◽  
Vertebral Compression Fracture ◽  
Compression Fracture ◽  
Balloon Kyphoplasty ◽  
Cement Leakage ◽  
Osteoporotic Vertebral Compression Fracture ◽  
Control Group ◽  
Compression Rate ◽  
Kyphotic Angle

Abstract Background This study was conducted to investigate the outcomes and complications of balloon kyphoplasty (KP) for the treatment of osteoporotic vertebral compression fracture (OVCF) in patients with rheumatoid arthritis (RA) and compare its radiological and clinical effects with OVCF patients without RA. Methods Ninety-eight patients in the RA group with 158 fractured vertebrae and 114 patients in the control group with 150 vertebrae were involved in this study. Changes in compression rate, local kyphotic angle, visual analog scale (VAS) and Oswestry disability index (ODI) scores, conditions of bone cement leakage, refracture of the operated vertebrae, and new adjacent vertebral fractures were examined after KP. In addition, patients in the RA group were divided into different groups according to the value of erythrocyte sedimentation rate (ESR), c-reactive protein (CRP), and whether they were glucocorticoid users or not to evaluate their influence on the outcomes of KP. Results KP procedure significantly improved the compression rate, local kyphotic angle, and VAS and ODI scores in both RA and control groups (p<0.05). Changes in compression rate and local kyphotic angle in the RA group were significantly larger than that in the control group (p<0.05), and patients with RA suffered more new adjacent vertebral fractures after KP. The outcomes and complications of KP from different ESR or CRP groups did not show significant differences. The incidence of cement leakage in RA patients with glucocorticoid use was significantly higher than those who did not take glucocorticoids. In addition, RA patients with glucocorticoid use suffered more intradiscal leakage and new adjacent vertebral fractures. Conclusions OVCF patients with RA obtained more improvement in compression rate and local kyphotic angle after KP when compared to those without RA, but they suffered more new adjacent vertebral fractures. Intradiscal leakage and new adjacent vertebral fractures occurred more in RA patients with glucocorticoid use. Trial registration Retrospectively registered.

scholarly journals Effect of the Use of Metronome Feedback on the Quality of Pediatric Cardiopulmonary Resuscitation

2021 ◽  
Vol 18 (15) ◽  
pp. 8087
Author(s):  
Dongjun Yang ◽  
Wongyu Lee ◽  
Jehyeok Oh
Keyword(s):  
Cardiopulmonary Resuscitation ◽  
Chest Compression ◽  
Healthcare Providers ◽  
Compression Rate ◽  
Audio Feedback ◽  
Simple Method ◽  
Compression Depth ◽  
Pediatric Resuscitation ◽  
Cpr Quality

Although the use of audio feedback with devices such as metronomes during cardiopulmonary resuscitation (CPR) is a simple method for improving CPR quality, its effect on the quality of pediatric CPR has not been adequately evaluated. In this study, 64 healthcare providers performed CPR (with one- and two-handed chest compression (OHCC and THCC, respectively)) on a pediatric resuscitation manikin (Resusci Junior QCPR), with and without audio feedback using a metronome (110 beats/min). CPR was performed on the floor, with a compression-to-ventilation ratio of 30:2. For both OHCC and THCC, the rate of achievement of an adequate compression rate during CPR was significantly higher when performed with metronome feedback than that without metronome feedback (CPR with vs. without feedback: 100.0% (99.0, 100.0) vs. 94.0% (69.0, 99.0), p < 0.001, for OHCC, and 100.0% (98.5, 100.0) vs. 91.0% (34.5, 98.5), p < 0.001, for THCC). However, the rate of achievement of adequate compression depth during the CPR performed was significantly higher without metronome feedback than that with metronome feedback (CPR with vs. without feedback: 95.0% (23.5, 99.5) vs. 98.5% (77.5, 100.0), p = 0.004, for OHCC, and 99.0% (95.5, 100.0) vs. 100.0% (99.0, 100.0), p = 0.003, for THCC). Although metronome feedback during pediatric CPR could increase the rate of achievement of adequate compression rates, it could cause decreased compression depth.

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