image performance
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2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Vladan Blahnik ◽  
Oliver Schindelbeck

Abstract Thanks to their portability, connectivity, and their image performance – which is constantly improving – smartphone cameras (SPCs) have been people’s loyal companions for quite a while now. In the past few years, multicamera systems have become well and truly established, alongside 3D acquisition systems such as time-of-flight (ToF) sensors. This article looks at the evolution and status of SPC imaging technology. After a brief assessment of the SPC market and supply chain, the camera system and optical image formation is described in more detail. Subsequently, the basic requirements and physical limitations of smartphone imaging are examined, and the optical design of state-of-the-art multicameras is reviewed alongside their optical technology and manufacturing process. The evolution of complementary metal oxide semiconductor (CMOS) image sensors and basic image processing is then briefly summarized. Advanced functions such as a zoom, shallow depth-of-field portrait mode, high dynamic range (HDR), and fast focusing are enabled by computational imaging. Optical image stabilization has greatly improved image performance, enabled as it is by built-in sensors such as a gyroscope and accelerometer. Finally, SPCs’ connection interface with telescopes, microscopes, and other auxiliary optical systems is reviewed.


Author(s):  
Mayada T. Wazi ◽  
Dalia S. Ali ◽  
Nadia M. G. Al-Saidi ◽  
Nawras A. Alawn

This work focused on introducing a new two-dimensional (2D) chaotic system. It is combined of some existing maps, the logistic, iterative chaotic map with infinite collapse, and Henon maps; we called it 2D-LCHM. The assessment of the actual performance of 2D-LCHM presents its sensitivity to a tiny change in the initial condition. Besides, its dynamics behavior is very complicated. It also has hyperchaotic properties and good ergodicity. The proposed system is occupied with designing a new image encryption system. Changing the image pixels’ locations is the primary step in the encryption process. The original image is splitting into four blocks to create four different keys based on 2D-LCHM; this reduces the computation time and increases the complexity. To obtain the encryption image, we have to repeat the partitioning process several times for each block. The encryption image’s efficiency is shown through some performance analysis such as; image histogram, the number of pixels changes rate (NPCR), the unified average changing intensity (UACI), pixels correlation, and entropy. The proposed system is compared with some efficient encryption algorithms in terms of chaocity attributes and image performance; the analysis result showed consistent improvement.


Author(s):  
Wenhui Yuan ◽  
Chuanjie Zhang ◽  
Hongyu Liang ◽  
Xin Wang ◽  
Minjie Shangguan ◽  
...  

2021 ◽  
Vol 2021 ◽  
pp. 1-6
Author(s):  
Jun Lin

In order to solve the problem of poor visual communication effect of impressionist painting colors and low accuracy of painting color enhancement by existing methods, this thesis proposes a research on the performance of impressionist painting color visual communication based on machine vision under the background of wireless network. This method can improve the vision, speed, and efficiency of communication, through the analysis of the characteristics of impressionist paintings, and determine the visual communication objects of impressionist painting colors.  The process of visual communication is analyzed, and the color matching of impressionist painting is completed with the help of BP neural network algorithm. On this basis, the histogram method is used to process the image brightness of impressionist paintings, the image interpolation method is used to process the image brightness of impressionist paintings, and the image is corrected by gamma correction to complete the image performance research. The color vision communication of impressionist painting needs to correct the gray scale error of impressionist painting and enhance the color of impressionist painting. The experimental results show that the accuracy of this method for the color matching of impressionist painting images is about 98%, which has a certain degree of credibility.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Zakiullah Ali ◽  
Christian Zakian ◽  
Vasilis Ntziachristos

AbstractImage performance in optoacoustic endoscopy depends markedly on the design of the transducer employed. Ideally, high-resolution performance is required over an expanded depth of focus. Current optoacoustic focused transducers achieve lateral resolutions in the range of tens of microns in the mesoscopic regime, but their depth of focus is limited to hundreds of microns by the nature of their spherical geometry. We designed an ultra-broadband axicon detector with a 2 mm central aperture and investigated whether the imaging characteristics exceeded those of a spherical detector of similar size. We show a previously undocumented ability to achieve a broadband elongated pencil-beam optoacoustic sensitivity with an axicon detection geometry, providing approximately 40 μm-lateral resolution maintained over a depth of focus of 950 μm—3.8 times that of the reference spherical detector. This performance could potentially lead to optoacoustic endoscopes that can visualize optical absorption deeper and with higher resolution than any other optical endoscope today.


2020 ◽  
Author(s):  
Ma'rifat Rajabova

In the article the folk games mentioned in Navoi’s lyrics arediscussed. The originality of the artistic expression of folk games in the poet’s poemsis analyzed.


2020 ◽  
Vol 10 (21) ◽  
pp. 7655
Author(s):  
Laura Peralta ◽  
Alessandro Ramalli ◽  
Michael Reinwald ◽  
Robert J. Eckersley ◽  
Joseph V. Hajnal

Transducers with a larger aperture size are desirable in ultrasound imaging to improve resolution and image quality. A coherent multi-transducer ultrasound imaging system (CoMTUS) enables an extended effective aperture through the coherent combination of multiple transducers. In this study, the discontinuous extended aperture created by CoMTUS and its performance for deep imaging and through layered media are investigated by both simulations and experiments. Typical image quality metrics—resolution, contrast and contrast-to-noise ratio—are evaluated and compared with a standard single probe imaging system. Results suggest that the image performance of CoMTUS depends on the relative spatial location of the arrays. The resulting effective aperture significantly improves resolution, while the separation between the arrays may degrade contrast. For a limited gap in the effective aperture (less than a few centimetres), CoMTUS provides benefits to image quality compared to the standard single probe imaging system. Overall, CoMTUS shows higher sensitivity and reduced loss of resolution with imaging depth. In general, CoMTUS imaging performance was unaffected when imaging through a layered medium with different speed of sound values and resolution improved up to 80% at large imaging depths.


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