公开(公告)号：US07463769B2

公开(公告)日：2008-12-09

申请号：US11156988

申请日：2005-06-20

申请人： Stephen S. Lin ,  Baining Guo ,  Heung-Yeung Shum ,  Jinwei Gu

发明人： Stephen S. Lin ,  Baining Guo ,  Heung-Yeung Shum ,  Jinwei Gu

IPC分类号： G06K9/00

CPC分类号： H04N1/603 ,  G06T7/80 ,  G06T7/90

摘要： Radiometric calibration of an image capture device (e.g., a digital camera) using a single image is described. The single image may be a color image or a grayscale image. The calibration identifies and analyzes edge pixels of the image that correspond to an edge between two colors or grayscale levels of a scene. Intensity distributions of intensities measured from the single image are then analyzed. An inverse response function for the image capture device is determined based on the intensity distributions. For a color image, the radiometric calibration involves calculating an inverse response function that maps measured blended colors of edge pixels and the associated measured component colors into linear distributions. For a grayscale image, the radiometric calibration involves deriving an inverse response function that maps non-uniform histograms of measured intensities into uniform distributions of calibrated intensities.

摘要翻译： 描述使用单个图像的图像捕获装置（例如，数码相机）的放射线校准。 单个图像可以是彩色图像或灰度图像。 校准识别和分析与场景的两种颜色或灰度级之间的边缘对应的图像的边缘像素。 然后分析从单个图像测量的强度的强度分布。 基于强度分布确定图像捕获装置的反应响应函数。 对于彩色图像，辐射校准包括计算反向响应函数，其将边缘像素的测量混合颜色和相关联的测量分量颜色映射为线性分布。 对于灰度图像，辐射校准涉及导出将测得的强度的不均匀直方图映射到校准强度的均匀分布的逆响应函数。

公开(公告)号：US07986830B2

公开(公告)日：2011-07-26

申请号：US12327680

申请日：2008-12-03

申请人： Stephen S. Lin ,  Baining Guo ,  Heung-Yeung Shum ,  Jinwei Gu

发明人： Stephen S. Lin ,  Baining Guo ,  Heung-Yeung Shum ,  Jinwei Gu

IPC分类号： G06K9/00

CPC分类号： H04N1/603 ,  G06T7/80 ,  G06T7/90

摘要： Radiometric calibration of an image capture device (e.g., a digital camera) using a single image is described. The single image may be a color image or a grayscale image. The calibration identifies and analyzes edge pixels of the image that correspond to an edge between two colors or grayscale levels of a scene. Intensity distributions of intensities measured from the single image are then analyzed. An inverse response function for the image capture device is determined based on the intensity distributions. For a color image, the radiometric calibration involves calculating an inverse response function that maps measured blended colors of edge pixels and the associated measured component colors into linear distributions. For a grayscale image, the radiometric calibration involves deriving an inverse response function that maps non-uniform histograms of measured intensities into uniform distributions of calibrated intensities.

摘要翻译： 描述使用单个图像的图像捕获装置（例如，数码相机）的放射线校准。 单个图像可以是彩色图像或灰度图像。 校准识别和分析与场景的两种颜色或灰度级之间的边缘对应的图像的边缘像素。 然后分析从单个图像测量的强度的强度分布。 基于强度分布确定图像捕获装置的反应响应函数。 对于彩色图像，辐射校准包括计算反向响应函数，其将边缘像素的测量混合颜色和相关联的测量分量颜色映射为线性分布。 对于灰度图像，辐射校准涉及导出将测得的强度的非均匀直方图映射到校准强度的均匀分布的反向响应函数。

公开(公告)号：US20090080772A1

公开(公告)日：2009-03-26

申请号：US12327680

申请日：2008-12-03

申请人： Stephen S. Lin ,  Baining Guo ,  Heung-Yeung Shum ,  Jinwei Gu

发明人： Stephen S. Lin ,  Baining Guo ,  Heung-Yeung Shum ,  Jinwei Gu

IPC分类号： G06K9/00

CPC分类号： H04N1/603 ,  G06T7/80 ,  G06T7/90

摘要： Radiometric calibration of an image capture device (e.g., a digital camera) using a single image is described. The single image may be a color image or a grayscale image. The calibration identifies and analyzes edge pixels of the image that correspond to an edge between two colors or grayscale levels of a scene. Intensity distributions of intensities measured from the single image are then analyzed. An inverse response function for the image capture device is determined based on the intensity distributions. For a color image, the radiometric calibration involves calculating an inverse response function that maps measured blended colors of edge pixels and the associated measured component colors into linear distributions. For a grayscale image, the radiometric calibration involves deriving an inverse response function that maps non-uniform histograms of measured intensities into uniform distributions of calibrated intensities.

摘要翻译： 描述使用单个图像的图像捕获装置（例如，数码相机）的放射线校准。 单个图像可以是彩色图像或灰度图像。 校准识别和分析与场景的两种颜色或灰度级之间的边缘对应的图像的边缘像素。 然后分析从单个图像测量的强度的强度分布。 基于强度分布确定图像捕获装置的反应响应函数。 对于彩色图像，辐射校准包括计算反向响应函数，其将边缘像素的测量混合颜色和相关联的测量分量颜色映射为线性分布。 对于灰度图像，辐射校准涉及导出将测得的强度的不均匀直方图映射到校准强度的均匀分布的逆响应函数。

公开(公告)号：US07450754B2

公开(公告)日：2008-11-11

申请号：US10809167

申请日：2004-03-23

申请人： Stephen S. Lin ,  Heung-Yeung Shum ,  Jinwei Gu

发明人： Stephen S. Lin ,  Heung-Yeung Shum ,  Jinwei Gu

IPC分类号： G06K9/00

CPC分类号： H04N1/603 ,  G06T7/80 ,  G06T7/90

摘要： A radiometric calibration system finds an inverse response function of a camera from a single digital image of a scene in which the actual colors of the scene are not known a priori. The system analyzes pixels of the image that correspond to an “edge” between two colors of the scene. These “edge” pixels represent a blended color formed from these two “component” colors, as measured by the camera. The system determines an inverse response function at least in part by: (a) finding suitable edge pixels; and (b) determining a function that maps the measured blended colors of edge pixels and their measured component colors into linear distributions. Reference data that includes predetermined inverse response functions of known cameras can be used in determining an inverse response function via a Bayesian Estimation.

摘要翻译： 辐射校准系统从场景的实际颜色先前不知道的场景的单个数字图像中发现摄像机的反向响应功能。 该系统分析对应于场景两种颜色之间的“边缘”的图像像素。 这些“边缘”像素表示由相机测量的由这两个“分量”颜色形成的混合色。 系统至少部分地通过以下方式确定反应响应函数：（a）找到合适的边缘像素; 和（b）确定将所测量的边缘像素的混合颜色及其测量的分量颜色映射成线性分布的函数。 包括已知摄像机的预定反向响应功能的参考数据可以用于经由贝叶斯估计来确定反向响应函数。

公开(公告)号：US08243071B2

公开(公告)日：2012-08-14

申请号：US12072925

申请日：2008-02-29

申请人： Jiaping Wang ,  Xin Tong ,  Stephen S. Lin ,  Baining Guo ,  Heung-Yeung Shum ,  Zhouchen Lin

发明人： Jiaping Wang ,  Xin Tong ,  Stephen S. Lin ,  Baining Guo ,  Heung-Yeung Shum ,  Zhouchen Lin

IPC分类号： G06T15/00 ,  G06T15/60 ,  G06K9/00

CPC分类号： G06T15/506 ,  G01N21/47 ,  G01N21/4738 ,  G06T15/50

摘要： An exemplary method includes providing image data for an illuminated physical sample of a heterogeneous translucent material, determining one or more material properties of the material based in part on a diffusion equation where one of the material properties is a diffusion coefficient for diffusion of radiation in the material and where the determining includes a regularization term for the diffusion coefficient, mapping the one or more material properties to a virtual object volume, assigning virtual illumination conditions to the virtual object volume, and rendering the virtual object volume using the virtual illumination conditions as a boundary condition for a system of diffusion equations of the virtual object volume. Other methods, devices and systems are also disclosed.

摘要翻译： 一种示例性方法包括提供用于异质半透明材料的照明物理样品的图像数据，部分地基于扩散方程来确定材料的一种或多种材料性质，其中材料性质之一是用于辐射的扩散的扩散系数 材料，并且其中确定包括扩散系数的正则化术语，将一个或多个材料属性映射到虚拟对象体积，将虚拟照明条件分配给虚拟对象体积，以及使用虚拟照明条件将虚拟对象体积呈现为 虚拟物体体积扩散方程组的边界条件。 还公开了其它方法，装置和系统。

公开(公告)号：US07129944B2

公开(公告)日：2006-10-31

申请号：US11000607

申请日：2004-12-01

申请人： Baining Guo ,  Stephen S. Lin ,  Heung-Yeung Shum ,  Ying-Qing Xu ,  Yanyun Chen

发明人： Baining Guo ,  Stephen S. Lin ,  Heung-Yeung Shum ,  Ying-Qing Xu ,  Yanyun Chen

IPC分类号： G06T15/60

CPC分类号： G06T15/50 ,  G06T15/00 ,  G06T17/00 ,  G06T2210/16 ,  G06T2210/62

摘要： A method and system for efficient synthesis of photorealistic free-form knitwear, where a single cross-section of yarn serves as the basic primitive for modeling entire articles of knitwear. This primitive, called the lumislice, describes radiance from a yarn cross-section based on fine-level interactions, including occlusion, shadowing, and multiple scattering, among yarn fibers. By representing yarn as a sequence of identical but rotated cross-sections, the lumislice can effectively propagate local microstructure over arbitrary stitch patterns and knitwear shapes. This framework accommodates varying levels of detail and capitalizes on hardware-assisted transparency blending. To further enhance realism, a technique for generating soft shadows from yarn is also introduced.

公开(公告)号：US07538766B2

公开(公告)日：2009-05-26

申请号：US11147921

申请日：2005-06-08

申请人： Kun Zhou ,  Yaohua Hu ,  Stephen S. Lin ,  Baining Guo ,  Heung-Yeung Shum

发明人： Kun Zhou ,  Yaohua Hu ,  Stephen S. Lin ,  Baining Guo ,  Heung-Yeung Shum

IPC分类号： G06T15/00

CPC分类号： G06T15/60

摘要： Pre-computed shadow fields are described. In one aspect, shadow fields for multiple entities are pre-computed. The shadow fields are pre-computed independent of scene configuration. The multiple entities include at least one occluding object and at least one light source. A pre-computed shadow field for a light source indicates radiance from the light source. A pre-computed shadow field for an occluding object indicates occlusion of radiance from the at least one light source.

摘要翻译： 描述预先计算的阴影场。 在一个方面，多个实体的影子字段被预先计算。 阴影场是独立于场景配置预先计算的。 多个实体包括至少一个闭塞对象和至少一个光源。 用于光源的预计算阴影场指示来自光源的辐射。 用于闭塞物体的预计算阴影场表示遮挡来自至少一个光源的辐射。

公开(公告)号：US07312797B2

公开(公告)日：2007-12-25

申请号：US11166559

申请日：2005-06-24

申请人： Xin Tong ,  Jiaping Wang ,  Stephen S. Lin ,  Baining Guo ,  Heung-Yeung Shum

发明人： Xin Tong ,  Jiaping Wang ,  Stephen S. Lin ,  Baining Guo ,  Heung-Yeung Shum

IPC分类号： G06T11/00

CPC分类号： G06T11/001 ,  G01N21/4795 ,  G06T15/506

摘要： Representing quasi-homogenous materials is described. In one aspect, quasi-homogenous materials are modeled to generate a material model of a physical sample. The material model identifies how light is scattered by the quasi-homogenous materials. The material model, independent of an object model of the physical sample, provides information that is useful to texture surfaces of arbitrary types and sizes of mesh models (e.g., representing the physical sample or other objects) with the quasi-homogenous materials.

摘要翻译： 描述了准均匀材料。 在一个方面，准均质材料被建模以产生物理样品的材料模型。 材料模型通过准均质材料识别光如何散射。 材料模型独立于物理样本的对象模型，提供了有用于使用准均质材料对任意类型和大小的网格模型（例如，表示物理样本或其他对象）的表面进行纹理的信息。

公开(公告)号：US08730240B2

公开(公告)日：2014-05-20

申请号：US13584158

申请日：2012-08-13

申请人： Jiaping Wang ,  Xin Tong ,  Stephen S. Lin ,  Baining Guo ,  Heung-Yeung Shum ,  Zhouchen Lin

发明人： Jiaping Wang ,  Xin Tong ,  Stephen S. Lin ,  Baining Guo ,  Heung-Yeung Shum ,  Zhouchen Lin

IPC分类号： G06T15/50 ,  G06T15/60 ,  G01N21/47

CPC分类号： G06T15/506 ,  G01N21/47 ,  G01N21/4738 ,  G06T15/50

摘要： An exemplary method includes providing image data for an illuminated physical sample of a heterogeneous translucent material, determining one or more material properties of the material based in part on a diffusion equation where one of the material properties is a diffusion coefficient for diffusion of radiation in the material and where the determining includes a regularization term for the diffusion coefficient, mapping the one or more material properties to a virtual object volume, assigning virtual illumination conditions to the virtual object volume, and rendering the virtual object volume using the virtual illumination conditions as a boundary condition for a system of diffusion equations of the virtual object volume. Other methods, devices and systems are also disclosed.

摘要翻译： 一种示例性方法包括提供用于异质半透明材料的照明物理样品的图像数据，部分地基于扩散方程来确定材料的一种或多种材料性质，其中材料性质之一是用于辐射的扩散的扩散系数 材料，并且其中确定包括扩散系数的正则化术语，将一个或多个材料属性映射到虚拟对象体积，将虚拟照明条件分配给虚拟对象体积，以及使用虚拟照明条件将虚拟对象体积呈现为 虚拟物体体积扩散方程组的边界条件。 还公开了其它方法，装置和系统。

公开(公告)号：US20120306878A1

公开(公告)日：2012-12-06

申请号：US13584158

申请日：2012-08-13

申请人： Jiaping Wang ,  Xin Tong ,  Stephen S. Lin ,  Baining Guo ,  Heung-Yeung Shum ,  Zhouchen Lin

发明人： Jiaping Wang ,  Xin Tong ,  Stephen S. Lin ,  Baining Guo ,  Heung-Yeung Shum ,  Zhouchen Lin

IPC分类号： G06T15/50

CPC分类号： G06T15/506 ,  G01N21/47 ,  G01N21/4738 ,  G06T15/50

摘要： An exemplary method includes providing image data for an illuminated physical sample of a heterogeneous translucent material, determining one or more material properties of the material based in part on a diffusion equation where one of the material properties is a diffusion coefficient for diffusion of radiation in the material and where the determining includes a regularization term for the diffusion coefficient, mapping the one or more material properties to a virtual object volume, assigning virtual illumination conditions to the virtual object volume, and rendering the virtual object volume using the virtual illumination conditions as a boundary condition for a system of diffusion equations of the virtual object volume. Other methods, devices and systems are also disclosed.

摘要翻译： 一种示例性方法包括提供用于异质半透明材料的照明物理样品的图像数据，部分地基于扩散方程来确定材料的一种或多种材料性质，其中材料性质之一是用于辐射的扩散的扩散系数 材料，并且其中确定包括扩散系数的正则化术语，将一个或多个材料属性映射到虚拟对象体积，将虚拟照明条件分配给虚拟对象体积，以及使用虚拟照明条件将虚拟对象体积呈现为 虚拟物体体积扩散方程组的边界条件。 还公开了其它方法，装置和系统。