公开(公告)号：US20060008141A1

公开(公告)日：2006-01-12

申请号：US11156988

申请日：2005-06-20

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

发明人： Stephen 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：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：US20050213813A1

公开(公告)日：2005-09-29

申请号：US10809167

申请日：2004-03-23

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

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

IPC分类号： G01J3/46 ,  G06T1/00 ,  G06T7/00 ,  G06T7/40 ,  H04N1/46 ,  H04N1/60 ,  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：US07933442B2

公开(公告)日：2011-04-26

申请号：US11694840

申请日：2007-03-30

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

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

IPC分类号： G06K9/00

CPC分类号： G06T19/00 ,  G06T13/00 ,  G06T2210/64

摘要： A method for modeling a time-variant appearance of a material is described. A sample analysis of a material sample is performed, wherein the sample analysis orders surface points of the material sample with respect to weathering from data captured at a single instant in time. An appearance synthesis using the sample analysis is performed, wherein the appearance synthesis generates a time-variant sequence of frames for weathering an object.

摘要翻译： 描述了用于对材料的时变外观进行建模的方法。 进行材料样品的样品分析，其中样品分析根据在单个时刻捕获的数据对材料样品的表面点进行排序。 执行使用样本分析的外观合成，其中外观合成生成用于风化对象的帧的时变序列。

公开(公告)号：US20060028468A1

公开(公告)日：2006-02-09

申请号：US10898435

申请日：2004-07-23

申请人： Yanyun Chen ,  Xin Tong ,  Stephen Lin ,  Baining Guo ,  Heung-Yeung Shum

发明人： Yanyun Chen ,  Xin Tong ,  Stephen Lin ,  Baining Guo ,  Heung-Yeung Shum

IPC分类号： G06T17/00

CPC分类号： G06T15/04

摘要： Techniques are provided for at least modeling any one of mesostructure shadowing, masking, interreflection and silhouettes on a surface, as well as subsurface scattering within a non-homogeneous volume. Such techniques include, at least, acquiring material parameters for a material sample, determining irradiance distribution values for the material sample, synthesizing the material sample onto a mesh of an object. The synthesized object may then be rendered by one of plural rendering techniques.

摘要翻译： 提供技术用于至少建模表面上的任何一种介观结构阴影，掩模，反射和剪影，以及非均匀体积内的地下散射。 这些技术至少包括获取材料样品的材料参数，确定材料样品的辐照度分布值，将材料样品合成到物体的网格上。 然后可以通过多个渲染技术之一来呈现合成对象。

公开(公告)号：US20050280648A1

公开(公告)日：2005-12-22

申请号：US10990244

申请日：2004-11-15

申请人： Xi Wang ,  Xin Tong ,  Stephen Lin ,  Baining Guo ,  Heung-Yeung Shum

发明人： Xi Wang ,  Xin Tong ,  Stephen Lin ,  Baining Guo ,  Heung-Yeung Shum

IPC分类号： G06T15/20 ,  G06T15/50 ,  G06T15/60 ,  G06T17/00 ,  G09G5/00

CPC分类号： G06T15/04

摘要： A “mesostructure renderer” uses pre-computed multi-dimensional “generalized displacement maps” (GDM) to provide real-time rendering of general non-height-field mesostructures on both open and closed surfaces of arbitrary geometry. In general, the GDM represents the distance to solid mesostructure along any ray cast from any point within a volumetric sample. Given the pre-computed GDM, the mesostructure renderer then computes mesostructure visibility jointly in object space and texture space, thereby enabling both control of texture distortion and efficient computation of texture coordinates and shadowing. Further, in one embodiment, the mesostructure renderer uses the GDM to render mesostructures with either local or global illumination as a per-pixel process using conventional computer graphics hardware to accelerate the real-time rendering of the mesostructures. Further acceleration of mesostructure rendering is achieved in another embodiment by automatically reducing the number of triangles in the rendering pipeline according to a user-specified threshold for acceptable texture distortion.

摘要翻译： “mesostructure渲染器”使用预先计算的多维“广义位移图”（GDM），以便在任意几何的开放和闭合表面上提供一般非高度场介观结构的实时渲染。 一般来说，GDM表示沿着体积样品内的任何点的任何射线投射到固体介观结构的距离。 给定预先计算的GDM，然后，介观结构渲染器在对象空间和纹理空间中联合计算介观结构可见度，从而实现纹理失真的控制和纹理坐标和阴影的有效计算。 此外，在一个实施例中，使用传统计算机图形硬件的介面结构渲染器使用GDM来渲染具有局部或全局照明的介观结构作为每像素处理，以加速介观结构的实时渲染。 在另一个实施例中，通过根据用户指定的可接受纹理失真的阈值自动减少渲染流水线中的三角形数量来实现进一步加速的介观结构渲染。

公开(公告)号：US07310101B2

公开(公告)日：2007-12-18

申请号：US10990142

申请日：2004-11-15

申请人： Xi Wang ,  Xin Tong ,  Stephen Lin ,  Baining Guo ,  Heung-Yeung Shum

发明人： Xi Wang ,  Xin Tong ,  Stephen Lin ,  Baining Guo ,  Heung-Yeung Shum

IPC分类号： G09G5/00 ,  G06T15/20 ,  G06T15/60 ,  G06T17/00

CPC分类号： G06T15/04

摘要： A “mesostructure renderer” uses pre-computed multi-dimensional “generalized displacement maps” (GDM) to provide real-time rendering of general non-height-field mesostructures on both open and closed surfaces of arbitrary geometry. In general, the GDM represents the distance to solid mesostructure along any ray cast from any point within a volumetric sample. Given the pre-computed GDM, the mesostructure renderer then computes mesostructure visibility jointly in object space and texture space, thereby enabling both control of texture distortion and efficient computation of texture coordinates and shadowing. Further, in one embodiment, the mesostructure renderer uses the GDM to render mesostructures with either local or global illumination as a per-pixel process using conventional computer graphics hardware to accelerate the real-time rendering of the mesostructures. Further acceleration of mesostructure rendering is achieved in another embodiment by automatically reducing the number of triangles in the rendering pipeline according to a user-specified threshold for acceptable texture distortion.

摘要翻译： “mesostructure渲染器”使用预先计算的多维“广义位移图”（GDM），以便在任意几何的开放和闭合表面上提供一般非高度场介观结构的实时渲染。 一般来说，GDM表示沿着体积样品内的任何点的任何射线投射到固体介观结构的距离。 给定预先计算的GDM，然后，介观结构渲染器在对象空间和纹理空间中联合计算介观结构可见度，从而实现纹理失真的控制和纹理坐标和阴影的有效计算。 此外，在一个实施例中，使用传统计算机图形硬件的介面结构渲染器使用GDM来渲染具有局部或全局照明的介观结构作为每像素处理，以加速介观结构的实时渲染。 在另一个实施例中，通过根据用户指定的可接受纹理失真的阈值自动减少渲染流水线中的三角形数量来实现进一步加速的介观结构渲染。

公开(公告)号：US07286135B2

公开(公告)日：2007-10-23

申请号：US10990244

申请日：2004-11-15

申请人： Xi Wang ,  Xin Tong ,  Stephen Lin ,  Baining Guo ,  Heung-Yeung Shum

发明人： Xi Wang ,  Xin Tong ,  Stephen Lin ,  Baining Guo ,  Heung-Yeung Shum

IPC分类号： G09G5/00 ,  G06T17/00 ,  G06T15/60 ,  G06T15/50

CPC分类号： G06T15/04

摘要： A “mesostructure renderer” uses pre-computed multi-dimensional “generalized displacement maps” (GDM) to provide real-time rendering of general non-height-field mesostructures on both open and closed surfaces of arbitrary geometry. In general, the GDM represents the distance to solid mesostructure along any ray cast from any point within a volumetric sample. Given the pre-computed GDM, the mesostructure renderer then computes mesostructure visibility jointly in object space and texture space, thereby enabling both control of texture distortion and efficient computation of texture coordinates and shadowing. Further, in one embodiment, the mesostructure renderer uses the GDM to render mesostructures with either local or global illumination as a per-pixel process using conventional computer graphics hardware to accelerate the real-time rendering of the mesostructures. Further acceleration of mesostructure rendering is achieved in another embodiment by automatically reducing the number of triangles in the rendering pipeline according to a user-specified threshold for acceptable texture distortion.

摘要翻译： “mesostructure渲染器”使用预先计算的多维“广义位移图”（GDM），以便在任意几何的开放和闭合表面上提供一般非高度场介观结构的实时渲染。 一般来说，GDM表示沿着体积样品内的任何点的任何射线投射到固体介观结构的距离。 给定预先计算的GDM，然后，介观结构渲染器在对象空间和纹理空间中联合计算介观结构可见度，从而实现纹理失真的控制和纹理坐标和阴影的有效计算。 此外，在一个实施例中，使用传统计算机图形硬件的介面结构渲染器使用GDM来渲染具有局部或全局照明的介观结构作为每像素处理，以加速介观结构的实时渲染。 在另一个实施例中，通过根据用户指定的可接受纹理失真的阈值自动减少渲染流水线中的三角形数量来实现进一步加速的介观结构渲染。