Fast Physically Correct Refocusing for Sparse Light Fields Using Block-Based Multi-Rate View Interpolation.

Digital refocusing has a tradeoff between complexity and quality when using sparsely sampled light fields for low-storage applications. In this paper, we propose a fast physically correct refocusing algorithm to address this issue in a twofold way. First, view interpolation is adopted to provide photorealistic quality at infocus-defocus hybrid boundaries. Regarding its conventional high complexity, we devised a fast line-scan method specifically for refocusing, and its 1D kernel can be 30× faster than the benchmark View Synthesis Reference Software (VSRS)-1D-Fast. Second, we propose a block-based multi-rate processing flow for accelerating purely infocused or defocused regions, and a further 3- 34× speedup can be achieved for high-resolution images. All candidate blocks of variable sizes can interpolate different numbers of rendered views and perform refocusing in different subsampled layers. To avoid visible aliasing and block artifacts, we determine these parameters and the simulated aperture filter through a localized filter response analysis using defocus blur statistics. The final quadtree block partitions are then optimized in terms of computation time. Extensive experimental results are provided to show superior refocusing quality and fast computation speed. In particular, the run time is comparable with the conventional single-image blurring, which causes serious boundary artifacts.

The High-efficiency LED Driver for Visible Light Communication Applications.

This paper presents a LED driver for VLC. The main purpose is to solve the low data rate problem used to be in switching type LED driver. The GaN power device is proposed to replace the traditional silicon power device of switching LED driver for the purpose of increasing switching frequency of converter, thereby increasing the bandwidth of data transmission. To achieve high efficiency, the diode-connected GaN power transistor is utilized to replace the traditional ultrafast recovery diode used to be in switching type LED driver. This work has been experimentally evaluated on 350-mA output current. The results demonstrate that it supports the data of PWM dimming level encoded in the PPM scheme for VLC application. The experimental results also show that system's efficiency of 80.8% can be achieved at 1-Mb/s data rate.

[Detection of Angiostrongylus cantonensis larvae with a high resolution melt PCR assay].

OBJECTIVE: To develop a detection method of the third-stage larvae of Angiostrongylus cantonensis by real-time PCR and high-resolution melt curve analysis. METHODS: A pair of specific primers was designed based on the internal transcribed spacer 1 (ITS1) region of the nuclear ribosomal DNA of A. cantonensis. The third-stage larvae of A. cantonensis were detected by real-time PCR and high-resolution melt curve analysis. The specificity of the method was analyzed by testing DNAs of A. cantonensis, Clonorchis sinensis, and Gnathostoma spinigerum. The genomic DNA were extracted from 1 to 10 third-stage larvae of A. cantonensis, respectively, and used to identify the sensitivity of the method. RESULTS: This method could specifically detect A. cantonensis and the detection limit reached to one larva. No amplification curve and melt curve were found in C. sinensis and G. spinigerum. CONCLUSION: Real-time PCR and high-resolution melt curve analysis show good specificity and sensitivity for detecting the third-stage larvae of A. cantonensis.