High Visual Effects Research Articles

Intramolecular charge transfer mediated dual-emission in multi-doped graphene quantum dots for anti-counterfeiting via liquid secret key

Multiple emission GQDs have always been the focus of researchers due to the unique emission characteristics and high-level application capabilities. Nevertheless, the most of GQDs with double emissions are formed by different chemical reactions, and the realization of double emission by adjusting the solvent environment is rarely reported. Here, the multi-doped and double-peak emissive GQDs (MD-GQDs) have been synthesized via one pot hydrothermal synthesis and re-dispersed in solvents with different polarity. Systematic characterizations of optical property indicate that the solvent polarity related double-peak emission photoluminescence is ascribed to the existence of multi-emissive centers in MD-GQDs from aromatic CO bond and surface/edge state (C–N/C–F). Furthermore, the double emission fluorescent mechanism of MD-GQDs has been proposed due to the electrostatic interaction between MD-GQDs and solvent molecules, which induces intramolecular charge transfer (ICT) effect in MD-GQDs. Finally, based on the unique solvent-induced discoloration behavior of MD-GQDs, a multi-mode anti-counterfeiting application based on organic solution as the secret key with easy operation and high visual effect is developed.

Web-based 3D visualization framework for time-varying and large-volume oceanic forecasting data using open-source technologies

There are limitations to traditional visualization solutions regarding real-time 3D visualization of time-varying and large-volume 3D gridded oceanographic data in a web environment. We adopted the open-source visualization technologies to implement a browser-based 3D visualization framework. The developed 3D visualization interfaces provide users 3DGIS experiences on a virtual globe and simultaneously provide efficient 3D volume rendering and enriched interactive volume analysis. Our experiments suggest that the well-designed Cesium and Plotly.js API allow researchers to easily establish 3D visualization applications while avoiding the requirements of intensive programming and computations. The case study conducted shows that the proposed methods is a feasible alternative web-based 3D visualization solution, which provides a faster rendering speed, high visual effects and on-the-fly 3D visualization of oceanographic data. Due to its open-source architecture and the simplicity of the adopted technologies, the visualization framework can be easily customized to visualize other scientific data with few modifications.

Development of a detector system to assess audience and occupational exposures at laser shows

Lasers have been used in the entertainment industry for over 40 yr. The laser provides high visual effects such as scanned images and beam patterns to enhance the overall show experience for the audience. Every year, a few suspected eye injuries are claimed. Currently, the risk arising from ocular exposure in laser shows is assessed theoretically before the event is approved, but there is no real-time monitoring of audience or occupational exposure during the show. This paper presents the development of a prototype field measurement instrument to aid in assessing the safety of laser shows. It describes in detail the hardware, user interface and software design considerations, gives system characteristics and illustrates its performance on examples of laser show effects.

大视场复眼结构图像处理算法研究

For the large field of view compound eye structure with multi-dimensional sub-eye imaging channels aranged on a curve surface, the segmentation-rotation-projection image processing algorithm was presented to realize a large field of view synthesized of multi-channels. By confirming the arrangement characteristics of the compound eye structure, the relation among all sub-eye images captured by corresponding imaging channels was analyzed and the overlap regions between nearby sub-eye images were eliminated. Meanwhile, by using the principle of geometrical optics and imaging optics, the relation between the sub-eye images and the three-dimensional projection space was studied to achieve the large field of view of two-dimensional sub-eye images synthesized in a three-dimensional space. An artificial compound eye consisted of 37 lenses with field of view over 118 degrees was fabricated and the corresponding sub-eye images captured by the fabricated compound eye structure were processed based on the presented algorithm. The results show that the resolution of the sub-eye images can be ensured of no decrease during the image processing precedure and the algorithm can effectively realise a large field of view synthesized of multi-channel images meeting the practical requirements with high visual effect. All of the above studies could put forword the application of the compound eye imaging system.

Reversible data hiding scheme based on dual stegano-images using orientation combinations

This work presents a novel reversible data hiding scheme based on combinations of pixel orientations located at two steganographic images to enhance embedding capacity and preserve good visual quality. Before secret data are embedded, the proposed scheme converts the data into a sequence of digits in a base-5 numeral system. The conversion then extends the abilitity to carry more secret data. When the secret data embedding procedure is performed, the original cover pixel value can only be modified by at most plus or minus one, thus ensuring that the stegano-image also has excellent visual quality. Moreover, image recovery does not require overhead information. Experimental results demonstrate that the embedding capacity is around 1.07 bpp and PSNR reaches 49.6 dB. The experimental comparison also reveals that the proposed scheme outperforms other related schemes in terms of embedding rate and retains a high visual effect of stegano-image.