摘要:
An apparatus and method are provided for providing efficient space leaping using neighbor guided emptiness map in octree traversal for fast ray casting. The apparatus and method include providing a min-max octree structure, marching a ray through the min-max structure; and skipping empty nodes associated with the min-max structure along the direction of the ray based on a memory byte included in each node comprising an emptiness state of neighbor nodes and a current node.
摘要:
A system and method for rendering an image that includes accessing image data and dividing the image data into one or more blocks. One or more corner points of the blocks are identified and rays are cast through voxel space of the image data in the direction of the corner points to determine one or more integrated values for the corner points. The integrated values are then sampled and compared to the sampled values for each combination of the corner points. A difference value (diffvalue) is calculated as a function of the comparison and an initial gradient (grad) is calculated as a function of a Reduced Path Octree (RPO) structure during the casting of rays. Next, a maximum gradient (maxGrad) is calculated based on the initial gradient (grad). Finally, an image processing operation is determined as a function of the maximum gradient (maxGrad) and the difference value (diffvalue). The image processing operation may perform interpolation to fill pixel values inside the image data, or it may perform recursive sub-division of the blocks, and cast and sample additional rays.
摘要:
A system and methods for volume rendering using n-pass sampling are disclosed. A plurality of first rays in a first density is sampled through a volume. Each of the first rays is in a separate section. A value of at least one first ray is compared to a first threshold. A plurality of second rays in a second density is sampled based on the comparison of the at least one first ray. The second rays are in a first section of the separate sections. The first section being for the at least one first ray. A value of at least one second ray is compared to a second threshold. A plurality of third rays is sampled in a second section spatially different than the first section based on the comparison of the at least one second ray. An image rendered from the sampling of at least the first rays is displayed.
摘要:
A system and method for increasing resolution of an object and increasing rendering speed by rendering with a lesser density for non-object regions. The system and method includes sampling a plurality of first rays in a first density through a volume, each first ray being in a separate section, if a sampling value difference of at least two first rays is above a first threshold, sampling a plurality of second rays in a second density, the second rays being in a first section of the separate sections, the first section being for one of the at least two first rays, and if a sampling value difference between a first one of the second rays and another ray is above a second threshold, sampling a plurality of third rays in a second section spatially different than the first section, the sampling of the third rays being at the second spatial density and the second section being a neighboring section to the first section.
摘要:
A system and methods for volume rendering using n-pass sampling are disclosed. A plurality of first rays in a first density is sampled through a volume. Each of the first rays is in a separate section. A value of at least one first ray is compared to a first threshold. A plurality of second rays in a second density is sampled based on the comparison of the at least one first ray. The second rays are in a first section of the separate sections. The first section being for the at least one first ray. A value of at least one second ray is compared to a second threshold. A plurality of third rays is sampled in a second section spatially different than the first section based on the comparison of the at least one second ray. An image rendered from the sampling of at least the first rays is displayed.
摘要:
A system and method for rendering an image that includes accessing image data and dividing the image data into one or more blocks. One or more corner points of the blocks are identified and rays are cast through voxel space of the image data in the direction of the corner points to determine one or more integrated values for the corner points. The integrated values are then sampled and compared to the sampled values for each combination of the corner points. A difference value (diffvalue) is calculated as a function of the comparison and an initial gradient (grad) is calculated as a function of a Reduced Path Octree (RPO) structure during the casting of rays. Next, a maximum gradient (maxGrad) is calculated based on the initial gradient (grad). Finally, an image processing operation is determined as a function of the maximum gradient (maxGrad) and the difference value (diffvalue). The image processing operation may perform interpolation to fill pixel values inside the image data, or it may perform recursive sub-division of the blocks, and cast and sample additional rays.
摘要:
A system and method for increasing resolution of an object and increasing rendering speed by rendering with a lesser density for non-object regions. The system and method includes sampling a plurality of first rays in a first density through a volume, each first ray being in a separate section, if a sampling value difference of at least two first rays is above a first threshold, sampling a plurality of second rays in a second density, the second rays being in a first section of the separate sections, the first section being for one of the at least two first rays, and if a sampling value difference between a first one of the second rays and another ray is above a second threshold, sampling a plurality of third rays in a second section spatially different than the first section, the sampling of the third rays being at the second spatial density and the second section being a neighboring section to the first section.
摘要:
An apparatus and method are provided for providing efficient space leaping using neighbor guided emptiness map in octree traversal for fast ray casting. The apparatus and method include providing a min-max octree structure, marching a ray through the min-max structure; and skipping empty nodes associated with the min-max structure along the direction of the ray based on a memory byte included in each node comprising an emptiness state of neighbor nodes and a current node.
摘要:
A method for performing direct rendering of a multi-volume data, having the steps of determining whether a volume of the multi-volume data is one of active and inactive via interaction with a ray for the multi-volume data, recording in triplicate a starting point and an end point of the ray for an eyespace, repeating the determining whether the volume is one of active and inactive via interaction with a ray for the multi-volume data and the recording in triplicate a starting point and an end point of the ray for an eyespace for all volumes of the multi-volume data, providing triples from all volumes to an array, sorting the array to create a sorted triples list array, breaking the ray into a plurality of segments using the sorted triples list array, determining which volumes are active for each of the segments via an active volume list, and sampling each segment of the ray to acquire an accumulated result.
摘要:
A system and method for rendering an MIP image that has reduced high frequency component loss and reduced chessboard artifacts. The method includes accessing volumetric data, having random noise. Rays are shot, or cast, through the volumetric data, onto a voxel grid, which has grid points. Sampling data along each ray is performed to obtain selected sample data points on the ray and a distance from a selected point to a nearest grid point is determined. A voxel intensity value is accessed at each selected point, as a function of the position of the selected point relative to the nearest grid point. The difference between the voxel intensity at each selected point is minimized an image is rendered from the volumetric data as a function of the minimizing step. Multiple methods may be used to minimize the difference between the voxel intensity at each selected point. These include for example 1.) applying a localized low pass filter, 2.) applying a localized high order interpolation kernel, and 3.) applying localized distance remapping methods.