实时形状匹配变形体动画

给出了一个仿真变形体的方法。物体被几何方法推动变形,操纵基于点的物体并且不需要连接信息,这是一个不需要任何预处理,计算简单,并提供无条件稳定的动态仿真方法。主要思想是通过几何约束替换能量和通过当前位置到目标位置的距离替换力。这些目标位置通过一个通用的无变形的静止状态和点云的当前变形状态之间的形状匹配来决定,因为点总是在定义好的位置被绘制,显式积分方法的过度不稳定问题被消除。相关物体表现方法的灵活性能被控制,相关内存和计算是有效的,动态仿真上的无条件稳定性让这个方法特别适合游戏开发。     

基于运动捕获数据的虚拟人动画研究

随着三维游戏等行业对计算机动画制作需求的增加,在三维动画制作软件中人工调整虚拟人动作的工作方式已经不再适合现在的计算机动画制作。运动捕获技术是直接记录物体的运动数据并将其用于生成计算机动画,具有高效率、所生成的动画真实感强等优点,因而获得了广泛应用。提出了一种利用运动捕获数据来生成动画的方法,基于运动捕获得到的数据建立并驱动三维骨架模型,从而产生骨架的运动,形成动画。该方法可以充分利用现有的大量运动捕获数据,因此具有较大的应用前景。     

浅析3D动漫造型协同创新设计方法

动漫造型的设计是一项依赖于脑力、创造力以及想象力的活动,能够体现出知识经济的特点,其中需要交互式的图形系统和分析计算为主的计算机辅助设计系统,这样才能为设计人员提供工具,实现人机交互．但是这并不能为设计人员的创造性思维有所帮助,也不能支持协同设计。本文首先对3D动漫造型的发展情况进行简述,之后分析3D动漫造型协同创新设计研究现状,结合现状提出3D动漫造型协同创新设计方法,从而引发动漫产业在国际市场上的发展,保证期发展前景的广阔性。     

草绘3维人体建模的模板形变方法

目的 采用草绘交互方式直接构造3维人体模型是当前人体建模研究的重要课题之一.提出一种草绘3维人体建模的模板形变方法.方法 针对输入的草图,首先,采用关节点定位方法获取草图中的人体关节点,根据人体结构学约束识别人体骨架结构,通过解析人体轮廓草图获取人体草图特征;其次,通过骨架模板和外观轮廓模板形变,将草图特征映射到3维人体模型,实现3维人体建模.结果 草图解析方法能有效提取草图特征,通过模板形变方法生成3维人体模型,并在模型上保持草图特征;能适应不同用户的绘制习惯,且生成的3维人体模型可用于人体动画设计.结论 提出一种草绘3维人体建模的模板形变方法,支持用户采用草绘方式进行3维人体模型设计,方法具有良好的用户适应性,对3维动画创作具有重要意义.     

Layered animation of captured data

normal volume of a triangle to convert individual triangles to a volumetric representation. A layered model is constructed to animate the reconstructed high-resolution surface. The model consists of 3 layers: a skeleton for animation from key-frame or motion capture; a low-resolution control model for real-time mesh deformation; and a high-resolution model to represent the captured surface detail. Initially the skeleton model is manually placed inside the low-resolution control model and high-resolution scanned data. Automatic techniques are introduced to map both the control model and captured data into a single layered model. The high-resolution captured data is mapped onto the low-resolution control model using the normal volume. The resulting model enables efficient, seamless animation by manipulation of the skeleton while maintaining the captured high-resolution surface detail. The animation of high-resolution captured data based on a low-resolution generic model of the object opens up the possibility of rapid capture and animation of new objects based on libraries of generic models. Published online: 2 October 2001     

Reconstruction of 3D human body pose from stereo image sequences based on top-down learning

This paper presents a novel method for reconstructing a 3D human body pose from stereo image sequences based on a top-down learning method. However, it is inefficient to build a statistical model using all training data. Therefore, the training data is hierarchically divided into several clusters to reduce the complexity of the learning problem. In the learning stage, the human body model database is hierarchically constructed by classifying the training data into several sub-clusters with silhouette images. The data of each cluster in the bottom level is represented by a linear combination of examples. In the reconstruction stage, the proposed method hierarchically searches a cluster for the best matching silhouette image using a silhouette history image (SHI). Then, the 3D human body pose is reconstructed from a depth image using a linear combination of examples method. By using depth information to reconstruct 3D human body pose, the similar poses in silhouette images are estimated as different 3D human body poses. The experimental results demonstrate that the proposed method is efficient and effective for reconstructing 3D human body poses.     

三维人脸捕获建模和动画技术综述

从历史发展和当前的研究现状的角度对三维人脸建模和动画算法进行综述,通过对三维捕获、参数化人脸建模和动画、表情克隆等问题及其典型算法的基本原理、优缺点等的分析,对它们的特性进行描述和比较.展望进一步值得研究的问题和方向.以期读者对三维人脸建模和动画的主流技术有较全面的了解,并对未来的研究工作有所帮助.     

Virtual human animation in natural language visualisation

Simulation motion of Virtual Reality (VR) objects and humans has experienced important developments in the last decade. However, realistic virtual human animation generation remains a major challenge, even if applications are numerous, from VR games to medical training. This paper proposes different methods for animating virtual humans, including blending simultaneous animations of various temporal relations with multiple animation channels, minimal visemes for lip synchronisation, and space sites of virtual human and 3D object models for object grasping and manipulation. We present our work in our natural language visualisation (animation) system, CONFUCIUS, and describe how the proposed approaches are employed in CONFUCIUS’ animation engine.     

面向服装合体性评价的虚拟人体建模及体型预测

提出了面向服装合体性评价的三维人体建模及预测建模方法。按照人体控制部位的比例对模型主体部分进行平面截取,通过比例缩放的方式实现个性化三维人体建模,最后通过NURBS进行曲面重建。同时,针对服装合体性评价服务的特点,引入体型随年龄变化知识库,根据用户的个性化要求提供顾客未来体型预测。实验结果表明该方法既实现简单,又可得到较满意的视觉效果,可为服装合体性评价等个性化定制服务奠定基础,具有广泛的应用前景。     

面向影视动画的真实感三维人脸快速建模算法

针对影视动画领域,利用LS_5000型三维激光扫描仪,提出了一套真实感三维人脸快速建模算法。只需输入真实演员人脸的三维扫描点云和未定标的照片,以及极少的人工交互,即可生成虚拟演员真实感的三维人脸模型（包括几何模型、纹理模型和面向动画的可变模型）。实验结果表明,算法输出的模型简洁规范,可直接应用于实际的影视动画制作,提高了人脸模型建模效率。     

基于单张图像的三维人脸建模与表情动画

在人机交互、数字娱乐等领域,传统的表情合成技术难以稳定地生成具有真实感的个性化人脸表情动画.为此,提出一种基于单张图像的三维人脸建模和表情动画系统.自动检测人脸在图像中的位置,自动定位人脸上的关键点,基于这些关键点和形变模型重建个性化三维人脸模型,对重建的人脸模型进行扩展得到完整的人脸网格,采用稀疏关键点控制的动画数据映射方法来驱动重建的人脸模型生成动态表情动画.实验结果表明,该方法稳定性强、自动化程度高,人脸模型与表情动画比较逼真.     

一种基于国标人体测量学数据的虚拟人建模方法

针对目前利用国标人体测量学数据构建的虚拟人模型,只有单一的骨骼层或皮肤层,不便于同时对虚拟人进行实时运动控制和皮肤动态变形研究的问题,提出一种利用GB 10000-88的19个人体测量学特征数据、用3ds max构造出虚拟人的皮肤网格、层级建模方法构建出虚拟人的骨骼关节运动模型与四元数球面混合插值技术相结合的虚拟人建模方法。实验结果表明,该方法构建的虚拟人双层模型有利于对准确的国标人体测量学数据的虚拟人角色进行建模、皮肤逼真变形、实时运动仿真和人机工效学分析。     

基于C3D数据的人体模型逆向动力学仿真分析方法

基于AnyBody人体建模仿真分析软件,采用试验得到的动作捕捉格式数据C3D文件,研究人体逆向动力学仿真分析方法,给出C3D驱动AnyBody人体运动仿真分析时的操作步骤、报错分析及其解决方案。仿真结果表明:人体模型基本参数设置、C3D参数设置、关键点的拟合和足底压力板参数调节是实现人体模型动态分析的关键,其能有效提高人体模型逆向动力学仿真精度。     

Lightweight wrinkle synthesis for 3D facial modeling and animation

We present a lightweight non-parametric method to generate wrinkles for 3D facial modeling and animation. The key lightweight feature of the method is that it can generate plausible wrinkles using a single low-cost Kinect camera and one high quality 3D face model with details as the example. Our method works in two stages: (1) offline personalized wrinkled blendshape construction. User-specific expressions are recorded using the RGB-Depth camera, and the wrinkles are generated through example-based synthesis of geometric details. (2) Online 3D facial performance capturing. These reconstructed expressions are used as blendshapes to capture facial animations in real-time. Experiments on a variety of facial performance videos show that our method can produce plausible results, approximating the wrinkles in an accurate way. Furthermore, our technique is low-cost and convenient for common users.     

Anthropometric body modeling based on orthogonal-view images

This paper presents an efficient and convenient method for creating an anthropometric model of a real person. First, 3D surface body models based on orthogonal-view photographs are reconstructed, and then skeletal systems for the reconstructed models are matched. A total of 26 anthropometric data items are measured using the surface and skeletal models. Some anthropometric data are measured directly on the deformed surface models, whereas others are estimated from the matched skeletal systems by kinematic analysis. A comparison of the anthropometric data from the reconstructed model with data from the corresponding real person demonstrates that the methodology proposed in this paper has high efficiency and precision. These models will satisfy consumer demand for higher product personalization and therefore product comfort, and they are likely to be widely used in future ergonomic research.Relevance to industryA convenient and efficient method to create individual anthropometric models is proposed. These models will help people create their own anthropometry databases and satisfy their demand for higher product personalization and therefore product comfort. The industrial applications include mass customization, computer-aided drafting, online custom-made design, and ergonomic evaluation.     

一种新型人体三维建模系统的设计

设计了一款新型的人体三维建模识别系统。系统采用2片TI TMS320C64x+数字信号处理器组成算法核心单元,采用S3C6410嵌入式处理器实现时序及总线控制功能。该系统无需人体佩戴任何骨骼传感器网络,仅通过光学摄像头及图像处理算法即可完成人体三维运动建模,并可实现多人体运动目标的实时追踪功能。给出了该系统的实时多人三维运动建模结果,实测效果良好。     

基于Kinect深度相机的实时三维人体动画

研究了一种基于H Anim标准的实时人体三维动画方法,首先对H Anim中人体肢体层次结构进行研究和分析,给出了进行人体动画的坐标变换方法;其次,基于OpenNI对Kinect获取的数据进行重新处理,采用逆运动学计算非根关节旋转矩阵;最后给出了系统流程及具体实验方法,采用OpenGL由实时获取的关节旋转矩阵驱动虚拟人实现了人体动画。实验结果表明,该算法可以较精确地提取人体三维姿态,实时重构人体运动。     

基于Kinect与网格几何变形的人脸表情动画

面部表情重建的实时性与重建效果的真实性是人脸表情动画的关键问题,提出一种基于Kinect人脸追踪和几何变形技术的面部表情快速重建新方法。使用微软的Kinect设备识别出表演者面部并记录其特征点数据,并利用捕捉到的特征点建立覆盖人脸的网格模型,从中选取变形使用的控制点数据,由于Kinect可以实时地自动追踪表演者面部,由此实现了利用三种不同变形算法对目标模型实时快速重建。实验结果表明,该方法简单易实施,不用在表演者面部做任何标定,可以自动地将人脸表情动作迁移到目标模型上,实现人脸表情快速重建,并且保证目标模型表情真实自然。     

Modeling and animation of facial expressions based on B-Splines

This paper describes a technique for the automatic adaptation of a canonical facial model to data obtained by a 3D laser scanner. The facial model is a B-spline surface with 13×16 control points. We introduce a technique by which this canonical model is fit to the scanned data and that takes into consideration the requirements for the animation of facial expressions. The animation of facial expressions is based on the facial action coding system (FACS). Using B-splines in combination with FACS, we automatically create the impression of a moving skin. To increase the realism of the animation we map textural information onto the B-spline surface.     

基于Maya脚本语言的虚拟士兵动画研究

在三维动画制作软件中,传统的人工调整虚拟人动作的工作方式已经不再适合现在的计算机动画制作。针对这一问题,提出了一种采用Maya脚本语言编程来实现人物动画控制的用户界面,在该界面中,动画师可以通过选择按钮移动滑块进行关键帧的设置,从而产生骨架的运动,形成动画。该方法可以提供对制作人物特征有用的工具,使得人物动画的制作更简单。