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：US20050280646A1

公开(公告)日：2005-12-22

申请号：US10965603

申请日：2004-10-13

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：US20070229502A1

公开(公告)日：2007-10-04

申请号：US11277935

申请日：2006-03-29

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

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

IPC分类号： G06T15/50

CPC分类号： G06T15/55

摘要： A shell radiance texture function (SRTF) is defined to record an outgoing radiance from a base volume of an object to be rendered. Using the SRTF, radiance values are precomputed and stored for the base volume. The object is rendered using the precomputed radiance values.

摘要翻译： 外壳辐射纹理函数（SRTF）被定义为记录要渲染的对象的基本卷的传出辐射。 使用SRTF，辐射值被预先计算并存储为基本卷。 使用预先计算的辐射值渲染对象。

公开(公告)号：US07184052B2

公开(公告)日：2007-02-27

申请号：US10965603

申请日：2004-10-13

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： G06T17/00 ,  G06T15/60 ,  G09G5/00 ,  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。

公开(公告)号：US20060279570A1

公开(公告)日：2006-12-14

申请号：US11147921

申请日：2005-06-08

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

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

IPC分类号： G06T15/50

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.

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：US08244057B2

公开(公告)日：2012-08-14

申请号：US11928951

申请日：2007-10-30

申请人： Stephen Lin ,  Baining Guo ,  Changyin Zhou

发明人： Stephen Lin ,  Baining Guo ,  Changyin Zhou

IPC分类号： G06K9/40

CPC分类号： G06T5/005 ,  G06T2207/10004 ,  G06T2207/20021 ,  G06T2207/20182 ,  H04N1/409 ,  H04N5/2171 ,  H04N5/2178

摘要： Removal of the effects of dust or other impurities on image data is described. In one example, a model of artifact formation from sensor dust is determined. From the model of artifact formation, contextual information in the image and a color consistency constraint may be applied on the dust to remove the dust artifacts. Artifacts may also be removed from multiple images from the same or different cameras or camera settings.

摘要翻译： 描述了去除灰尘或其他杂质对图像数据的影响。 在一个示例中，确定来自传感器灰尘的人造物形成的模型。 从人造物形成的模型，图像中的上下文信息和颜色一致性约束可以应用于灰尘以去除灰尘伪像。 人造物也可以从相同或不同的相机或相机设置的多个图像中移除。

公开(公告)号：US20070146506A1

公开(公告)日：2007-06-28

申请号：US11384063

申请日：2006-03-17

申请人： Stephen Lin ,  Baining Guo ,  Sing Kang ,  Yuanjie Zheng

发明人： Stephen Lin ,  Baining Guo ,  Sing Kang ,  Yuanjie Zheng

IPC分类号： H04N5/217

CPC分类号： H04N5/3572 ,  G06T5/007 ,  G06T7/11 ,  G06T2207/10024 ,  G06T2207/20012 ,  G06T2207/20016

摘要： A system and process for determining the vignetting function of an image and using the function to correct for the vignetting is presented. The image can be any arbitrary image and no other images are required. The system and process is designed to handle both textured and untextured segments in order to maximize the use of available information. To extract vignetting information from an image, segmentation techniques are employed that locate image segments with reliable data for vignetting estimation. Within each image segment, the system and process capitalizes on frequency characteristics and physical properties of vignetting to distinguish it from other sources of intensity variation. The vignetting data acquired from segments are weighted according to a presented reliability measure to promote robustness in estimation.

摘要翻译： 提出了一种用于确定图像的渐晕功能并使用功能来校正渐晕的系统和过程。 图像可以是任意图像，并且不需要其他图像。 系统和过程被设计为处理纹理和非纹理段，以便最大限度地利用可用信息。 为了从图像中提取渐晕信息，采用定位图像片段以进行晕影估计的可靠数据的分割技术。 在每个图像片段中，系统和过程利用渐晕的频率特性和物理特性来区别其与强度变化的其他来源。 根据提出的可靠性度量对从片段获取的渐晕数据进行加权，以提高估计的鲁棒性。

公开(公告)号：US07663623B2

公开(公告)日：2010-02-16

申请号：US11612394

申请日：2006-12-18

申请人： Kun Zhou ,  Jiaping Wang ,  Stephen Lin ,  Baining Guo

发明人： Kun Zhou ,  Jiaping Wang ,  Stephen Lin ,  Baining Guo

IPC分类号： G06T15/50 ,  G06T15/00

CPC分类号： G06T15/55

摘要： A method, device and system is provided for providing global illumination of a scene. For example, global illumination may be provided in a rendered 3-dimensional image that may contain objects and/or light sources. Radiance functions or visibility functions may further be represented by scaling of spherical harmonics functions in the spherical harmonics domain. For example, scaling of spherical harmonics coefficients corresponding to a spherical function may be performed based on a spherical harmonics scaling transformation matrix based on an angular scaling function.

摘要翻译： 提供了一种用于提供场景的全局照明的方法，装置和系统。 例如，可以在可以包含对象和/或光源的渲染的三维图像中提供全局照明。 亮度函数或可见度函数可以进一步通过球面谐波域中的球谐函数的缩放来表示。 例如，可以基于基于角度缩放函数的球面谐波缩放变换矩阵来执行对应于球面函数的球谐函数的缩放。

公开(公告)号：US20100085360A1

公开(公告)日：2010-04-08

申请号：US12245708

申请日：2008-10-04

申请人： Zhong Ren ,  Kun Zhou ,  Stephen Lin ,  Baining Guo

发明人： Zhong Ren ,  Kun Zhou ,  Stephen Lin ,  Baining Guo

IPC分类号： G06T15/50

CPC分类号： G06T15/50

摘要： Techniques are described for rendering a volume of scattering media, in particular by computing radiances of points or voxels in the scattering media. A set of sample points in the scattering media are found. Radiances of the sample points are computed. Radiance gradients of the sample points are computed from the radiances. The radiances and gradients are used to interpolate radiances throughout the scattering media. The set of sample points may be computed in an iterative dynamic manner in order to concentrate samples near features (e.g., shadow edges) of the scattering media.

摘要翻译： 描述了用于渲染体积的散射介质的技术，特别是通过计算散射介质中的点或体素的辐射。 发现散射介质中的一组采样点。 计算采样点的辐射。 采样点的辐射梯度由辐射计算。 辐射和梯度用于在整个散射介质中内插辐射。 可以以迭代动态方式计算采样点集合，以便将样本集中在散射介质的特征（例如，阴影边缘）附近。