基于相关匹配算法的目标角度和尺度检测研究

鉴于灰度相关匹配算法无法检测目标的角度和尺度变化信息,提出了一种利用已知模板创建带有角度和尺度信息的多模板来检测待匹配图像中目标的角度和尺度信息的方法。分析了模板创建过程中有关模板扩展大小的问题,并针对四维相关系数分布情况提出了一种峰值分割方法。鉴于该方法数据计算量比较大,介绍了相关系数的一些特性和一种快速搜索方法。通过Matlab仿真证明,该方法克服了直接利用四维相关系数作为权值致使误匹配点的问题,能正确匹配具有一定范围角度和尺度变化的目标。

基于λ/4波片的标度因数稳定性分析

针对实际应用中由于光纤电流互感器λ/4波片误差容限较小导致标度因数不稳定的问题,提出了一种标度因数补偿的新方法,该补偿方法大大提高了波片的误差容限,从而有效地提高了光纤电流互感器的标度因数稳定性。通过理论分析,给出了λ/4 波片的理论模型,分析了要得到 0.2%及 0.01%的标度因数精度所要求的波片的对轴角度误差和相位延迟误差容限。应用峰值分割法对波片误差容限进行了补偿,结果表明,同补偿前的数据相比,当标度因数精度分别为0.2%和0.01%时,补偿后的对轴角度误差和相位延迟误差容限分别提高了约4.7倍和11倍,因此对于这两个不同的精度,光纤电流互感器的标度因数稳定性也同时分别提高了约4.7倍和 11倍。并且从数值上可以看出,所需的标度因数精度越高,补偿效果越明显。通过应用峰值分割法进行补偿,有效地减少了光纤电流互感器的标度因数不稳定性带来的测量精度误差。

Colored 3D surface reconstruction using Kinect sensor

A colored 3D surface reconstruction method which effectively fuses the information of both depth and color image using Microsoft Kinect is proposed and demonstrated by experiment.Kinect depth images are processed with the improved joint-bilateral filter based on region segmentation which efficiently combines the depth and color data to improve its quality.The registered depth data are integrated to achieve a surface reconstruction through the colored truncated signed distance fields presented in this paper.Finally,the improved ray casting for rendering full colored surface is implemented to estimate color texture of the reconstruction object.Capturing the depth and color images of a toy car,the improved joint-bilateral filter based on region segmentation is used to improve the quality of depth images and the peak signal-to-noise ratio(PSNR)is approximately 4.57 d B,which is better than 1.16 d B of the joint-bilateral filter.The colored construction results of toy car demonstrate the suitability and ability of the proposed method.