Topic
Map extent
About: Map extent is a research topic. Over the lifetime, 39 publications have been published within this topic receiving 734 citations.
Papers
Patent•
17 Dec 2010TL;DR: In this paper, a map plane is divided into a plurality of cells and an origin cell corresponding to the geotagged event is identified, and density values are allocated to cells surrounding the origin cell based on geodetic distances between geographic coordinates corresponding to surrounding cells and the geographic coordinate of the event.
Abstract: Techniques in a data processor for drawing a density surface on a map in a manner that more accurately accounts for projection distortion in the map. According to one embodiment, data is maintained that represents a geotagged event. A map plane is divided into a plurality of cells and an origin cell corresponding to the geotagged event is identified. Density values are allocated to cells surrounding the origin cell based on geodetic distances between geographic coordinates corresponding to surrounding cells and the geographic coordinate of the geotagged event. A density surface based on the cell allocations is then displayed on a map. By allocating density values to cells based on geodetic distances, the resulting density surface displayed on the map more accurately accounts for projection distortions in the area of the map on which density surface is displayed.
125 citations
Patent•
14 Mar 2007TL;DR: In this article, a set of fixed matching windows is used for points of the image for which the depth map is to be determined, and the average number (O) of matching windows that a pixel of the footprint (FP) belongs to is less than one plus the number of pixels in the footprint divided by 15 (O
Abstract: Window based matching is used for determining a depth map from images obtained from different orientations. A set of fixed matching windows is used for points of the image for which the depth is to be determined. The set of matching windows covers a footprint of pixels around the point of the image, and the average number (O) of matching windows that a pixel of the footprint (FP) belongs to is less than one plus the number of pixels in the footprint divided by 15 (O
66 citations
Patent•
3 Aug 2012TL;DR: In this paper, the first unit of area is rendered at a first density of map data and the second unit of areas is rendered with a second density of data that is lower than the first density.
Abstract: A graphics or image rendering system, such as a map image rendering system, determines a viewing window of a map surface to be displayed, wherein the viewing plane is at an angle of incidence with respect to the map surface. The method generally determines a depth boundary along the map surface where a height projection of a depth increment of a first unit of area is lower than a threshold height increment at a non-zero angle of incidence and at a single zoom level magnification. The method renders the first unit of area within the depth boundary and a second unit of area outside the depth boundary. The first unit of area is rendered at a first density of map data and the second unit of area is rendered at a second density of map data that is lower than the first density of map data.
43 citations
Patent•
29 Oct 2013TL;DR: In this paper, a depth map is generated by a mapping among relative depth values in a field of view of an image based on a difference between pixels of a first image and pixels of the second image.
Abstract: Aspects of depth map generation and post capture focusing and re-focusing are described. According to one embodiment, a depth map is generated. The depth map may include a mapping among relative depth values in a field of view of an image based on a difference between pixels of a first image and pixels of a second image. An edge map may also be generated by identifying edges in at least one of the first image or the second image. Using the depth map and the edge map, the relative depth values in the depth map may be smoothed using the edge map. In this manner, certain discontinuities in depth values may be smoothed within edge-bounded regions defined by the edge map. The depth map may be used for focusing and re-focusing, for example, or for object extraction, scene understanding, or gesture recognition, among other imaging processes.
42 citations
Patent•
11 Feb 2011TL;DR: In this paper, a probabilistic occupancy grid for the voxels is generated and an n-layer height map is constructed by generating an occupancy grid and then using the weights assigned to each voxel in a three dimensional grid along rays extending from the reference point through the pixels in the image.
Abstract: Methods of generating a three dimensional representation of an object in a reference plane from a depth map including distances from a reference point to pixels in an image of the object taken from a reference point. Weights are assigned to respective voxels in a three dimensional grid along rays extending from the reference point through the pixels in the image based on the distances in the depth map from the reference point to the respective pixels, and a height map including an array of height values in the reference plane is formed based on the assigned weights. An n-layer height map may be constructed by generating a probabilistic occupancy grid for the voxels and forming an n-dimensional height map comprising an array of layer height values in the reference plane based on the probabilistic occupancy grid.
38 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 1 |
| 2020 | 1 |
| 2019 | 1 |
| 2018 | 2 |
| 2017 | 2 |
| 2014 | 4 |