# US 2017/0289526 A1 · Calibration device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0289526 A1 - Document ID: US20170289526A1 - Status: Published application - Kind: A1 - Application number: 15/513,842 - Filed: 2015-10-16 - Published: 2017-10-05 - Earliest claimed: 2014-10-24 - Assignees: Hitachi, Ltd. - Applicants: Hitachi, Ltd. - Inventors: So SASATANI; Ryou YUMIBA; Masaya ITOH - Web page: https://patentgrep.com/patent/US20170289526A1 ## CPC - H04N 13/246: Calibration of cameras - G06T 7/70: Determining position or orientation of objects or cameras (camera calibration G06T7/80) - G06T 7/80: Analysis of captured images to determine intrinsic or extrinsic camera parameters, i.e. camera calibration - G06T 7/85: {Stereo camera calibration} - G06V 20/53: {Recognition of crowd images, e.g. recognition of crowd congestion} - H04N 13/302: for viewing without the aid of special glasses, i.e. using autostereoscopic displays - H04N 17/002: {for television cameras} - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION - G06T: IMAGE DATA PROCESSING OR GENERATION, IN GENERAL - G06V: IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING ## Abstract In a calibration device, entry work of coordinate information on a real space is not required. An imaging system is configured to include an image acquisition unit which acquires an image from an imaging device, an object extraction unit which extracts a plurality of objects from the image, a characteristic information addition unit which adds geometry information that indicates geometric relationships among the plurality of objects to each set of objects as characteristic information, a camera parameter estimation unit which obtains image coordinates of the objects in accordance with the characteristic information to estimate camera parameters based on the characteristic information and the image coordinates, and a camera parameter output unit which outputs the camera parameters. ## Claims ### Claim 1 An imaging system, comprising: an image acquisition unit which acquires an image from an imaging device; an object extraction unit which extracts a plurality of objects from the image; a characteristic information addition unit which adds geometry information that indicates geometric relationships among the plurality of objects to each set of objects as characteristic information; a camera parameter estimation unit which obtains image coordinates of the objects in accordance with the characteristic information to estimate camera parameters based on the characteristic information and the image coordinates; and a camera parameter output unit which outputs the camera parameters. ### Claim 2 (depends on 1) The imaging system according to claim 1, wherein, in a case where the characteristic information is vertical, the camera parameter output unit obtains, among the plurality of objects, for one existing on a horizontal plane on a real space, two arbitrary image coordinates of the object, and among the plurality of objects, for one vertical to a horizontal plane on a real space, two image coordinates on an axis in a height direction on a real space in an object area of the object. ### Claim 3 (depends on 1) The imaging system according to claim 1, wherein, in a case where the characteristic information is level, the camera parameter output unit obtains, among the plurality of objects, for one vertical to a horizontal plane on a real space, two image coordinates on an axis in a height direction on a real space in an object area. ### Claim 4 (depends on 1) The imaging system according to claim 1, comprising a display screen capable of displaying the image, selecting the plurality of objects, and adding characteristic information to the each arbitrary set of objects among the plurality of objects. ### Claim 5 (depends on 1) The imaging system according to claim 1, wherein the object extraction unit carries out scene recognition of the image, detects a plurality of objects from the image based on results of the scene recognition, and adds the characteristic information. ### Claim 6 The imaging system, comprising: an image acquisition unit which acquires an image from an imaging device; an object tracking unit which detects and tracks an object from the image, the object tracking unit including: an object recognition unit which determines whether a first object detected at a first time and a second object detected at a second time are identical; and an object information storage unit which acquires, in a case where the objects are identical, information on height of the objects on images at the first and second times and adds geometry information that indicates a geometric relationship established between the first and second objects as characteristic information to each set of objects; a camera parameter estimation unit which estimates camera parameters based on the characteristic information and the image coordinates; and a camera parameter output unit which outputs the camera parameters. ### Claim 7 (depends on 1) The imaging system according to claim 1, wherein a plurality of the imaging devices is installed, the system comprising a camera parameter accuracy confirmation unit which acquires three-dimensional information of the object by calculating a distance between an object on the image and the imaging device based on the estimated camera parameters, and adjusts values of the camera parameters based on the three-dimensional information. ### Claim 8 (depends on 7) The imaging system according to claim 7, wherein a stereo camera device displays, in the camera parameter accuracy confirmation unit, a viewpoint-converted image where the three-dimensional information is viewed from different viewpoints based on the camera parameters and changes the viewpoint-converted image once the values of the two camera parameters are changed. ### Claim 9 (depends on 8) The imaging system according to claim 8, wherein a stereo camera device detects an object using an image of the viewpoint-converted image.