A Signal-Processing Framework for Occlusion of 3D Scene to Improve the Rendering Quality of Views

2020 ◽  
Vol 29 ◽  
pp. 8944-8959
Author(s):  
Changjian Zhu ◽  
Hong Zhang ◽  
Qiuming Liu ◽  
Zhixian Zhuang ◽  
Li Yu
Photonics ◽  
2021 ◽  
Vol 8 (8) ◽  
pp. 298
Author(s):  
Juan Martinez-Carranza ◽  
Tomasz Kozacki ◽  
Rafał Kukołowicz ◽  
Maksymilian Chlipala ◽  
Moncy Sajeev Idicula

A computer-generated hologram (CGH) allows synthetizing view of 3D scene of real or virtual objects. Additionally, CGH with wide-angle view offers the possibility of having a 3D experience for large objects. An important feature to consider in the calculation of CGHs is occlusion between surfaces because it provides correct perception of encoded 3D scenes. Although there is a vast family of occlusion culling algorithms, none of these, at the best of our knowledge, consider occlusion when calculating CGHs with wide-angle view. For that reason, in this work we propose an occlusion culling algorithm for wide-angle CGHs that uses the Fourier-type phase added stereogram (PAS). It is shown that segmentation properties of the PAS can be used for setting efficient conditions for occlusion culling of hidden areas. The method is efficient because it enables processing of dense cloud of points. The investigated case has 24 million of point sources. Moreover, quality of the occluded wide-angle CGHs is tested by two propagation methods. The first propagation technique quantifies quality of point reproduction of calculated CGH, while the second method enables the quality assessment of the occlusion culling operation over an object of complex shape. Finally, the applicability of proposed occlusion PAS algorithm is tested by synthetizing wide-angle CGHs that are numerically and optically reconstructed.


1999 ◽  
Vol 5 (2) ◽  
pp. 147-153 ◽  
Author(s):  
Dingjun Cui ◽  
Ian A. Craighead

The requirements for a special approach for the quality assessment of small high-speed centrifugal fans are outlined and a new parameter designating the noise levels from the product in comprehensive form will be discussed and described as a criterion for such quality assessment.By applying techniques of signal processing and condition monitoring, the sources of the vibration and noise in different sections of the product can be identified, then the noise from each source from different components can be determined. Using this criterion, more aspects of the quality of the products can be assessed and suggestions to improve the quality of the products can be made. Finally, the assessment of a number ofvacuum cleaner motor/fan units available in the commercial market will be presented and compared with conventional specifications. It will be shown that the new parameter provides a more useful indication of appliance quality.


2014 ◽  
Vol 45 (1) ◽  
pp. 1149-1152
Author(s):  
Masaaki Kabe ◽  
Toshiyuki Nagatsuma ◽  
Amane Higashi ◽  
Tae Nakahara ◽  
Kojiro Ikeda ◽  
...  

2020 ◽  
Vol 10 (4) ◽  
pp. 24-36
Author(s):  
Nguyen Quang Vinh

In the modern navigation system, the height channel is always the most unstable channel. Combination processing the height measurement signals by using the Kalman filter algorithm can improve the precision of the high measurement. However, in the process of performing the signal processing algorithm by using the Kalman filter, the transition time to obtain the set status is long. Moreover, within different flight conditions, the inertia height meter will be combined with the supporting height meter to get the structure of the combination height meter in order to process the height measurement signals more precisely. In this article, the authors proposed using the criterion for evaluating the observable level to improve the quality of height measurement signal processing. The research results were simulated on three combined high measurements, in which the inertia height meter (IHM) (the basic meter) was combined with one or two supporting height meters (the radio height meter [RHM] and the barometer [AHM]) to show the correctness of the proposed algorithm.


2020 ◽  
Vol 10 (19) ◽  
pp. 6956
Author(s):  
Yisak Kim ◽  
Juyoung Park ◽  
Hyungsuk Kim

Acquisition times and storage requirements have become increasingly important in signal-processing applications, as the sizes of datasets have increased. Hence, compressed sensing (CS) has emerged as an alternative processing technique, as original signals can be reconstructed using fewer data samples collected at frequencies below the Nyquist sampling rate. However, further analysis of CS data in both time and frequency domains requires the reconstruction of the original form of the time-domain data, as traditional signal-processing techniques are designed for uncompressed data. In this paper, we propose a signal-processing framework that extracts spectral properties for frequency-domain analysis directly from under-sampled ultrasound CS data, using an appropriate basis matrix, and efficiently converts this into the envelope of a time-domain signal, avoiding full reconstruction. The technique generates more accurate results than the traditional framework in both time- and frequency-domain analyses, and is simpler and faster in execution than full reconstruction, without any loss of information. Hence, the proposed framework offers a new standard for signal processing using ultrasound CS data, especially for small and portable systems handling large datasets.


2019 ◽  
Vol 201 ◽  
pp. 04004
Author(s):  
Evgenii Lutsenko

The LumiCal electromagnetic calorimeter is designed for the forward region of future electron-positron colliders, such as CLIC and ILC. It is intended to improve hermeticity of detectors by detecting electrons, positrons, and photons at small angles. Currently, the detector prototypes are studied in the beam test conditions. An important part of the signal processing is the digital filltering implemented in the read-out electronics, influencing the precision and quality of gathered data. In this article two schemes of digital filltering of gathered signal from test beam for the LumiCal detector prototype are presented.


2020 ◽  
Vol 53 (3-4) ◽  
pp. 635-648 ◽  
Author(s):  
Arumuga Maria Devi Thanu ◽  
Muthukumar Devadoss ◽  
Kumar Parasuraman

In the recent years, electrical, electronics, and telecommunications have far-famed a rare improvement, the quantity of nonlinear loads has inflated. Many electric power consumption devices are sensitive to magnetic attraction disturbances, created through nearby devices, which might have an effect on the power quality for several industry units or may be domestic users. Poor quality of power leads to fault of devices and instrumentation instability in a short period. Systematically, some research and analysis are required to monitor the disturbances of power quality which increases quality of power. This paper consists of power quality analysis on RLC circuits with voltage and current magnification values through Hyperspectral signal processing. The voltage changes and harmonic disturbances can be simulated finely with the MATLAB–Simulink simulation results and the theoretical analysis display. The simulated outcome and the Hyperspectral processing offer data and identification of power quality variances and additional control measures accurately.


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