A non-photorealistic rendering framework with temporal coherence for augmented reality
A non-photorealistic rendering framework with temporal coherence for augmented reality
复制标题
具有时间一致性的增强现实非真实感渲染框架
DOI：
10.1109/ismar.2012.6402552
复制
发表时间：
2012
期刊：
影响因子：
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通讯作者：
B. MacIntyre
中科院分区：
文献类型：
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作者：
Jiajian Chen;Greg Turk;B. MacIntyre
许多增强现实（AR）应用需要真实的和虚拟内容的无缝混合，作为增加沉浸感和改善用户体验的关键。真实感渲染和非真实感渲染（NPR）是实现这一目标的两种方法。与真实感渲染相比，非真实感渲染对真实的和虚拟的内容都进行了风格化处理，使它们难以区分。保持时间相干性是NPR的一个关键挑战。我们提出了一个NPR框架，利用模型空间信息的时间一致性的支持。我们的系统目标绘画渲染风格的NPR。在此渲染框架中，有三个主要步骤可用于创建连贯的结果：张量场创建、画笔锚放置和画笔笔划重塑。为了实现最终渲染结果的时间一致性，我们提出了一种新的基于投影的表面采样算法，该算法在模型表面上生成锚点。这些样本的2D投影均匀分布在图像空间中，以实现最佳画笔笔划放置。我们还提出了一个通用的方法来平均各种属性的笔触纹理，如他们的骨架和颜色，以进一步提高时间的一致性。我们将这些方法应用于静态和动画模型，以创建AR的绘画渲染风格。与现有的图像空间算法相比，我们的方法呈现AR与NPR效果具有高度的一致性。
Many augmented reality (AR) applications require a seamless blending of real and virtual content as key to increased immersion and improved user experiences. Photorealistic and non-photorealistic rendering (NPR) are two ways to achieve this goal. Compared with photorealistic rendering, NPR stylizes both the real and virtual content and makes them indistinguishable. Maintaining temporal coherence is a key challenge in NPR. We propose a NPR framework with support for temporal coherence by leveraging model-space information. Our systems targets painterly rendering styles of NPR. There are three major steps in this rendering framework for creating coherent results: tensor field creation, brush anchor placement, and brush stroke reshaping. To achieve temporal coherence for the final rendered results, we propose a new projection-based surface sampling algorithm which generates anchor points on model surfaces. The 2D projections of these samples are uniformly distributed in image space for optimal brush stroke placement. We also propose a general method for averaging various properties of brush stroke textures, such as their skeletons and colors, to further improve the temporal coherence. We apply these methods to both static and animated models to create a painterly rendering style for AR. Compared with existing image space algorithms our method renders AR with NPR effects with a high degree of coherence.