【作者】 刘磊；

【导师】 赵志敏；

【作者基本信息】 南京航空航天大学 ， 光学工程， 2012， 博士

【摘要】 头部姿态信息测量是机器视觉与模式识别领域中的重要研究课题，其主要研究目的是测量头部在三维空间中的姿态信息参数。现有的头部姿态信息测量技术多存在设备复杂和计算量大等缺点。本文基于光电信息测量原理，提出了一种基于单目视觉测量与几何目标相结合的动态头部姿态信息测量新方法。通过对固定于人体头部的几何目标进行光学成像分析，获得几何目标成像与姿态角度之间的关系，进而实现人体头部姿态信息的计算。本文提出并设计的头部姿态信息测量系统通过实验测量验证达到了预期效果。本文研究为使头部姿态信息测量更加简单实用提供了一种新的有效途径。全文的主要研究内容和创新性工作如下：（1）提出了基于圆形目标成像分析的人体头部姿态信息测量方法。通过对现有头部姿态信息测量技术的分析，提出了基于单目视觉测量与几何目标相结合的头部姿态信息测量技术。研究了球形和圆形两种几何目标在头部姿态信息测量中的优缺点，并选择圆形作为头部姿态信息测量的附加几何目标。对圆形目标的设计方法及安装方式进行了研究。通过分析运动过程中圆形目标及标注其上的两条直径在摄像机成像平面的成像变化，实现对人体头部姿态信息的测量。（2）提出了一种基于光学成像分析的圆形目标旋转角度计算方法。基于摄像机光学成像原理，分析了当圆形目标与摄像机处于不同相对姿态时圆形目标的成像。并在此基础上，分别分析了当人体头部做简单运动和复杂运动时标注于圆形目标上两条直径的成像变化情况。并通过几何推导给出了简单情况和复杂情况下圆形目标俯仰角、滚转角和偏航角的计算方法。（3）提出了一种基于直径成像分析的圆形目标姿态二义性消除方法。从圆形目标图像中提取两条直径所成的像，通过分析直径所成像的斜率以及半径所成像的长度，判断圆形目标相对于初始位置的运动方向，进而实现确定圆形目标姿态，可以消除在计算圆形目标姿态时通常出现的姿态二义性现象。（4）提出了一种普通光学成像条件下圆形目标图像的处理方法。在普通光学成像条件下，头部姿态信息测量系统所采集的圆形目标图像多属于弱成像质量图像。提出了小波降噪、灰度变换、直方图处理及图像二值化等弱成像质量图像处理的步骤。采用该方法，圆形目标图像质量得到提高，并且获得了圆形目标的二值图像。（5）研究了基于圆形目标成像分析的人体头部姿态信息测量系统的结构，并设计了头部姿态信息测量的软件系统。提出了基于圆形目标直径的头部初始位置判定方法，并提出基于斜率的两条直径区分方法。对本文中设计的系统进行了实验研究，通过模拟实验和人体头部实验，验证了本系统的可行性。本项研究具有重要的理论和实用价值。更多还原

【Abstract】 Measurement of human head pose is an important research topic in the fields of machine visionand pattern recognition. The main research purpose is to measure the pose parameters of the head inthree-dimensional space. There are shortcomings such as complex equipments and huge computationsin the existing technologies of head pose measurement. Based on the photoelectronic informationmeasurement principle, a new measurement method of dynamic head pose based on monocular visionmeasurement and geometric target is proposed. The relation between the geometric target’s imagingand pose angles is obtained by analyzing the optical imaging of the geometric target which is fixed onthe head, and then the head pose parameters are calculated. The system of head pose measurementproposed in this paper can meet the expected effect by the experiments. The research in this paper hasproposed a new effective approach to make the head pose measurement system simplier and morepractical. The main research and innovations are as follows:(1) A measurement method of head pose using imaging analysis of circular target is proposed inthis paper. The measurement technology of head pose based on monocular vision measurement andgeometric target is proposed after analyzing the existing technologies of head pose measurement. Theadvantages and faults of two common geometric targets-sphere and circle, are studied in themeasurement of head pose and at last the circle is chosen as the additive geometric target. Thedesigning and installation of circular target are studied. The information of head pose can be measuredby analysing the imaging changes of circular target and two diameters marked on the circular target inthe camera image plane.(2) The computation methods of rotation angles of circular target based on the optical imaginganalysis are proposed. Based on the principle of camera optical imaging, the imagings of circulartarget are analyzed when the circular target and the camera are in different poses. And on these bases,the imaging changes of the two diameters are studied separately when the head does simple andcomplex motions. The computation methods of pitch angle, roll angle and yaw angle in simple andcomplex situations are proposed separately by the geometric derivation method.(3) A method of eliminating the pose duality of circular target based on imaging analysis ofdiameter is proposed. The imagings of the two diameters are extracted from the circular target images.The motion direction with respect to the initial position can be judged by analyzing the slopes of thetwo diameters’ imagings and the lengths of radii’s imagings. And then the pose of the circular targetcan be determined. This method can elimitate the pose duality which often occurs in the process ofcalculating the pose of circular target.(4) The processing method of circular target images in the circumstance of common opticalimaging is studied. The circular targer images are often with poor imaging quality when the head posemeasurement system works in the circumstance of common optical imaging. The processingprocedures of wavelet denosing, gray level transformation, histogram processing, and imagebinarization are proposed for the images with poor imaging quality. The quality of the image isimproved after the processing. And binary images of circular target are obtained.(5) The composition of the measurement system of head pose based on imaging analysis ofcircular target is studied. The software system of the measurement of head pose is also designed. Thedecision method of head’s initial position based on the diameters of the circular target is proposed. The method of distinguishing the two diameters based on the slopes of the diameters is also proposed.Experimental research is also done using the system we proposed in this paper. The fesiblity of thesystem is verified by simulated experiment and head experiment. The research in this paper is ofsignificant theoretical and practical value.更多还原