Using a Scene Illuminating Infrared Emitter Array in a Video Monitoring Camera to Estimate the Position of the Camera

摘要

A process estimates height and tilt of a camera having an image sensor array and IR illuminators. The process identifies multiple distinct subsets of the illuminators. For multiple heights and tilts, the process constructs dictionary entries that correspond to the camera having the height and tilt above a floor. Each entry includes light intensity values for pixels in images corresponding to activating each of the subsets of illuminators. For each of the subsets, the process receives an image of a scene captured while the subset is emitting light and the other illuminators are not. The process uses the captured images to identify a floor region corresponding to a floor in the scene. The process forms a vector including pixels from the captured images in the identified floor region and estimates the height and tilt of the camera by comparing the vector to the dictionary entries.

主权项

1. A method of estimating height and tilt angle of a camera system having a 2-dimensional array of image sensors and a plurality of IR illuminators in fixed locations relative to the array of image sensors, comprising:
at a computing device having one or more processors, and memory storing one or more programs configured for execution by the one or more processors:
identifying a plurality of distinct subsets of the IR illuminators;partitioning the image sensors into a plurality of pixels;for each of the plurality of distinct subsets of the IR illuminators, receiving a captured IR image of a scene taken by the array of image sensors while the respective subset of the IR illuminators are emitting IR light and the IR illuminators not in the respective subset are not emitting IR light;using at least one of the captured IR images to identify a floor region corresponding to a floor in the scene;forming a vector including pixels from the captured IR images in the identified floor region; andestimating a camera height and camera tilt angle relative to the floor by comparing the vector to a dictionary, wherein the dictionary includes entries that correspond to the camera system having a plurality of heights and tilt angles.