Hong Kong Applied Science and Technology Research Institute Company, Limited

Jihui Zhang

Man Wai Kwan

Cheng Hsiung Liu

Yiu Man Lam

Wang Kit Wilson Thong

Jiaxin Yan

Kong Chau Tsang

Zhuobin Lin

Jiewei Ding

Zizhou Wang

Qifeng Liao

Zijian Xu

An iterative multi-image camera orientation estimation comprising: capturing an image of a scene before the camera; detecting line segments in the scene; computing a maximum likelihood (ML) camera orientation by maximizing a likelihood objective by rotating the camera's X-Y-Z coordinate system such that it is being optimally aligned with the line segments in at least two of the frontal, the lateral, and the vertical orthogonal directions; estimating a maximum a-posteriori (MAP) camera orientation that maximizes an a-posteriori objective such that the MAP camera orientation is an optimal value in between the priori camera orientation and the ML camera orientation, and is closer to the one with smaller uncertainty; iterating the multi-image camera orientation estimation with the priori camera orientation and its corresponding priori camera orientation uncertainty set to the computed MAP camera orientation and its corresponding uncertainty respectively until the uncertainty is lower than a threshold.

Apparatus and method for estimating camera orientation relative to ground surface

A method for estimating camera orientation relative to a ground surface. Line segments are detected from an image captured by a camera. A first virtual cube having three orthogonal vanishing points with a random 3D orientation is superimposed on to the image. The line segments of the image are classified grouped into 3D-directional groups. A second virtual cube is superimposed on to the image with an initial 3D orientation. An optimal 3D orientation of the second virtual cube is computed by iteratively changing the 3D orientation of the second virtual cube and measuring perpendicular distances of the three orthogonal vanishing points to the three line segment groups in each iteration starting with the initial 3D orientation, wherein the optimal 3D orientation of the second virtual cube being one that provides shortest perpendicular distances. Co-variances of the orthogonal vanishing points of the second virtual cube at the optimal orientation are computed. Ground orientation is computed from the second virtual cube at the optimal orientation.

Described is a method of reducing uplink inter-cell interference in a cellular communications network. The method comprises identifying in a cell any user equipments (UEs) which are susceptible to interference (ISUs) from another UE, particularly another UE in a neighboring cell. The method includes identifying in said cell any UEs causing interference (ICUs) to at least one neighboring cell and, more particularly, causing interference to a UE in a neighboring cell. The identified ISUs and ICUs are combined into a priority list for frequency resource reservation or allocation in said cell. The method may include limiting the identification of ISUs and ICUs to a selected number of UEs within the cell.

Method of reducing uplink inter-cell interference in a cellular communications network

A method and system for tracking a position and orientation of a target object that moves along a two-dimensional plane, a camera to generate video frames of the target object, and a processor configured to correct perspective scaling of a current one of the video frames; estimate a current location and angle of the target object using a motion model or its previous location/angle; cut out a region of interest from the current video frame around the estimated current location; resize the region of interest to shrink its size by a predetermined ratio M (width=width/M, height=height/M) or equivalently reducing the image resolution of the region of interest by the ratio M (resolution=resolution/M); track a new location of the target object by template matching the current region of interest with a previously stored template; and either conclude the tracked target object location and angle are accurate and updating the template if a stopping criterion is reached with indication of successful tracking, or proceed with a refinement method to refine the tracked location and angle until the stopping criterion is eventually reached.

Object tracking method and system using iterative template matching

This invention provides a method for a first communication device, such as a base station, to estimate a channel-quality profile of a channel when a second communication device, e.g., a user equipment, returns only channel-quality indicators (CQIs) of selected subbands and a wideband CQI. The profile is obtained by including, for any two neighboring frequencies of the selected subbands, an estimated CQI of a middle frequency between the two neighboring frequencies. After translating the CQIs of the two neighboring frequencies into corresponding linear CQI values, a linear estimated-CQI value for the middle frequency is determined by subtracting an offset from an average of said corresponding linear CQI values. The offset is determined according to a frequency separation between the two neighboring frequencies. Preferably, the offset is linearly proportional to the frequency separation. Interpolation, preferably linear interpolation, is used to obtain linear CQI values of other frequencies.

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Hong Kong, China

Jihui Zhang